hash
stringlengths 32
32
| doc_id
stringlengths 7
13
| section
stringlengths 3
121
| content
stringlengths 0
3.82M
|
|---|---|---|---|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.21 Flow-status AVP
|
The Flow-Status AVP (AVP code 511) is of type Enumerated, and describes whether the IP flow(s) are enabled or disabled. The following values are defined: • ENABLED-UPLINK (0): - This value shall be used to enable associated uplink IP flow(s) and to disable associated downlink IP flow(s). If any downlink RTCP IP flow(s) are identified by the Flow_Usage AVP(s), those flow(s) shall be enabled. • ENABLED-DOWNLINK (1): - This value shall be used to enable associated downlink IP flow(s) and to disable associated uplink IP flow(s). If any uplink RTCP IP flow(s) are identified by the Flow_Usage AVP(s), those flow(s) shall be enabled. • ENABLED (2): - This value shall be used to enable all associated IP flow(s) in both directions. • DISABLED (3): - This value shall be used to disable all associated IP flow(s) in both directions. If any RTCP IP flow(s) are identified by the Flow_Usage AVP(s), those flow(s) shall be enabled. During session modifications when using the two phases method to modify existing media component(s), this value shall be used to indicate a reserve operation and shall be used to keep all existing associated IP flow(s) enabled. Existing committed parameters which have been committed during the last session initiation/modification procedure are maintained in spite of the reserve operation. • REMOVED (4): - This value shall be used to remove all associated IP flow(s). The IP Filters for the associated IP flow(s) shall be removed. The associated IP flows shall not be taken into account when deriving the authorized QoS.
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.22 Flow-usage AVP
|
The Flow-Usage AVP (AVP code 512) is of type Enumerated, and provides information about the usage of IP Flows. The following values are defined: • NO_INFORMATION (0): - This value is used to indicate that no information about the usage of the IP flow is being provided. ETSI ETSI TS 183 017 V3.2.1 (2010-02) 28 • RTCP (1): - This value is used to indicate that an IP flow is used to transport RTCP. • NO_INFORMATION is the default value. NOTE: An AF may choose not to identify RTCP flows, e.g. in order to avoid that RTCP flows are always enabled by the server.
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.23 Specific-action AVP
|
The Specific-Action AVP (AVP code 513) is of type Enumerated. Within a SPDF initiated Re-Authorization Request, the Specific-Action AVP determines the type of the action. Within an initial AA-request the AF may use the Specific-Action AVP to request specific actions from the server at the bearer events and to limit the contact to such bearer events where specific action is required. If the Specific-Action AVP is omitted within the initial AA-request, no notification of any of the events defined below is requested. The following values from TS 129 209 [4] are used: • INDICATION_OF_LOSS_OF_BEARER (2): - Within a RAR, this value shall be used when the server reports a loss of a bearer (e.g. the bandwidth detected in the BGF is 0 kbit) to the AF. In the AAR, this value indicates that the AF requests the server to provide a notification at the loss of a bearer. • INDICATION_OF_RECOVERY_OF_BEARER (3): - Within a RAR, this value shall be used when the server reports a recovery of a bearer (e.g. the bandwidth detected by the BGF is modified from 0 kbit to another value) to the AF. In the AAR, this value indicates that the AF requests the server to provide a notification at the recovery of a bearer. • INDICATION_OF_RELEASE_OF_BEARER (4): - In the AAR, this value indicates that the AF requests the SPDF to provide a notification at the removal of a bearer. In a RAR message, the SPDF indicates to the AF that a transport layer error has occurred. In case of failure of a multicast request, the RAR message may include the address of the UE that requested the multicast flow and the flow description of the flow. These information may be used by the AF to forward a failure message to the UE. In addition, the present document defines two new values: • INDICATION_OF_SUBSCRIBER_DETACHMENT (6): - In the AAR, this value indicates that the AF requests the SPDF to provide a notification at the detachment of a subscriber. In a RAR message, the SPDF indicates to the AF that the subscriber has been detached. • INDICATION_OF_RESERVATION_EXPIRATION (7): - In the AAR, this value indicates that the AF requests the SPDF to provide a notification when the reservation is about to expire. In a RAR message, the SPDF indicates to the AF that the reservation is about to expire. Other values from TS 129 209 [4] are not relevant at the Gq' interface and are not used. If received by the SPDF, these values are ignored.
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.24 Max-requested-bandwidth-DL AVP
|
The Max-Requested-Bandwidth-DL AVP (AVP code 515) is of type Unsigned32, and it indicates the maximum requested bandwidth in bits per second for a downlink IP flow. The bandwidth contains all the overhead coming from the IP-layer and the layers above, e.g. IP, UDP, RTP and RTP payload. ETSI ETSI TS 183 017 V3.2.1 (2010-02) 29
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.25 Max-requested-bandwidth-UL AVP
|
The Max -Bandwidth-UL AVP (AVP code 516) is of type Unsigned32, and it indicates the maximum requested bandwidth in bits per second for an uplink IP flow. The bandwidth contains all the overhead coming from the IP-layer and the layers above, e.g. IP, UDP, RTP and RTP payload.
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.26 Media-component-description AVP
|
The Media-Component-Description AVP (AVP code 517) is of type Grouped, and it contains service information for a single media component within an AF session. It may be based on the SDI exchanged between the AF and the AF client in the UE. The information may be used by the server to determine authorized QoS and IP flow classifiers for bearer authorization and charging rule selection. Within one Diameter message, a single IP flow shall not be described by more than one Media-Component-Description AVP. Bandwidth information and Flow-Status information provided within the Media-Component-Description AVP applies to all those IP flows within the media component, for which no corresponding information is being provided within Media-Sub-Component AVP(s). If a Media-Component-Description AVP is not supplied, or if optional AVP(s) within a Media-Component-Description AVP are omitted, but corresponding information has been provided in previous Diameter messages, the previous information for the corresponding IP flow(s) remains valid. All IP flows within a Media-Component-Description AVP are permanently disabled by supplying a Flow Status AVP with value "REMOVED". The server may delete corresponding filters and state information. Each Media-Component-Description AVP shall contain either zero, or one, or two Codec-Data AVPs. In the case of conflicts, information contained in other AVPs either within this Media-Component-Description AVP, or within the corresponding Media-Component-Description AVP in a previous message, shall take precedence over information within the Codec-Data AVP(s). The AF shall provision all the available information in other applicable AVPs in addition to the information in the Codec-Data AVP, if such other AVPs are specified. - If the Media-Component-Description AVP contains two Codec-Data AVPs, one of them shall represent an SDP offer and the other one the corresponding SDP answer. - If the Media-Component-Description AVP contains one Codec-Data AVP, and this AVP represents an SDP offer, the AF shall provision the corresponding SDP answer information in a Codec-Data AVP within a subsequent Gq' message. AVP format: Media-Component-Description ::= < AVP Header: 517 > { Media-Component-Number }; Ordinal number of the media comp. *[ Media-Sub-Component ] ; Set of flows for one flow identifier [ AF-Application-Identifier ] [ Media-Type ] [ Max-Requested-Bandwidth-UL ] [ Max-Requested-Bandwidth-DL ] [ Flow-Status ] [ RS-Bandwidth ] [ RR-Bandwidth ] [ Reservation-Class ] [ Reservation-Priority ] [ Transport-Class ] *[ Codec-Data ] *[ Media-Authorization-Context-Id ]
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.27 Media-component-number AVP
|
The Media-Component-Number AVP (AVP code 518) is of type Unsigned32, and it contains the ordinal number of the media component, assigned according to the rules in annex C of TS 129 207 [12]. ETSI ETSI TS 183 017 V3.2.1 (2010-02) 30
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.28 Media-sub-component AVP
|
The Media-Sub-Component AVP (AVP code 519) is of type Grouped, and it contains the requested QoS and filters for the set of IP flows identified by their common Flow-Identifier. The Flow-Identifier is defined in TS 129 207 [12]. Possible Bandwidth information and Flow-Status information provided within the Media-Sub-Component AVP takes precedence over information within the encapsulating Media Component Description AVP. If a Media-Sub-Component- AVP is not supplied, or if optional AVP(s) within a Media-Sub-Component AVP are omitted, but corresponding information has been provided in previous Diameter messages, the previous information for the corresponding IP flow(s) remains valid, unless new information is provided within the encapsulating Media-Component-Description AVP. If Flow-Description AVP(s) are supplied, they replace all previous Flow-Description AVP(s), even if a new Flow-Description AVP has the opposite direction as the previous Flow-Description AVP. All IP flows within a Media-Sub-Component- AVP are permanently disabled by supplying a Flow Status AVP with value "REMOVED". The server may delete corresponding filters and state information. AVP format: Media-Sub-Component ::= < AVP Header: 519 > { Flow-Number } ; Ordinal number of the IP flow 0*2[ Flow-Description ] ; UL and/or DL [ Flow-Status ] [ Flow-Usage ] [ Max-Requested-Bandwidth-UL ] [ Max-Requested-Bandwidth-DL ]
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.29 Media-type AVP
|
The Media-Type AVP (AVP code 520) is of type Enumerated, and it determines the media type of a session component. The media types indicate the type of media in the same way as the SDP media types with the same names defined in [11]. The following values are defined: • AUDIO (0) • VIDEO (1) • DATA (2) • APPLICATION (3) • CONTROL (4) • TEXT (5) • MESSAGE (6) • OTHER (0xFFFFFFFF)
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.30 RR-bandwidth AVP
|
The RR-Bandwidth AVP (AVP code 521) is of type Unsigned32, and it indicates the maximum required bandwidth in bits per second for RTCP receiver reports within the session component, as specified in RFC 3556 [16]. The bandwidth contains all the overhead coming from the IP-layer and the layers above, i.e. IP, UDP and RTCP.
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.31 RS-bandwidth AVP
|
The RS-Bandwidth AVP (AVP code 522) is of type Unsigned32, and it indicates the maximum required bandwidth in bits per second for RTCP sender reports within the session component, as specified in RFC 3556 [16]. The bandwidth contains all the overhead coming from the IP-layer and the layers above, i.e. IP, UDP and RTCP. ETSI ETSI TS 183 017 V3.2.1 (2010-02) 31
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.32 SIP-forking-indication AVP
|
The SIP_Forking AVP (AVP code 523) is of type Enumerated, and describes if several SIP dialogues are related to one Diameter session: • SINGLE_DIALOGUE (0) - This value is used to indicate that the Diameter session relates to a single SIP dialogue. This is the default value applicable if the AVP is omitted. • SEVERAL_DIALOGUES (1) - This value is used to indicate that the Diameter session relates to several SIP dialogues.
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.33 Service-Class AVP
|
The Service-Class AVP (AVP code 459) is of type UTF8String, and it contains the service class requested by the AF. The service class is to be checked against local policies in the SPDF.
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.34 Transport-Class AVP
|
The Transport-Class AVP (AVP code 311) is of type Unsigned32, and it contains an integer used as an index pointing to a class of transport services to be applied (e.g. forwarding behaviour).
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.35 Overbooking-indicator
|
The Overbooking-indicator AVP (AVP code 460) is of type Enumerated. Indicates that the SPDF should require processing the resource request in overbooking mode. The following values are specified The overbooking-indicator may be used when having a session initiation or when having a session modification. • Overbooking-indicator (0) means that no overbooking mode is required • Overbooking-indicator (1) means that overbooking is mode required
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.36 Codec-Data AVP
|
The Codec-Data AVP (AVP code 524) is of type OctetString. The Codec-Data AVP shall contain codec related information known at the AF. This information shall be encoded as described in clause 5.3.7 of [19].
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.37 Authorization-Package-Id
|
The Authorization-Package-Id AVP (AVP code 461) is of type UTF8String, and it identifies an authorization context requested by the AF for the session. The SPDF forwards this information transparently over the Rq interface (ES 283 026 [14]). 7.3.38 Media-Authorization-Context-Id The Media-Authorization-Context-Id AVP (AVP code 462) is of type UTF8String, and it identifies an authorization context requested by the AF associated to a media flow. The SPDF forwards this information transparently over the Rq interface (ES 283 026 [14]).
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.3.39 Logical-Access-ID AVP
|
The Logical-Access-ID AVP (AVP code 302 13019) is of type OctetString. It is defined in [15]. ETSI ETSI TS 183 017 V3.2.1 (2010-02) 32
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.4 Use of namespaces
|
This clause contains the namespaces that have either been created in the present document, or the values assigned to existing namespaces managed by IANA.
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.4.1 AVP codes
|
The present document assigns the AVP values from the AVP Code namespace managed by ETSI for its Diameter vendor-specific applications. See clause 7.3.
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.4.2 Experimental-result-code AVP values
|
The present document assigns the Experimental-Result-Code AVP values from the AVP Code namespace managed by ETSI for its Diameter vendor-specific applications. See clause 7.2.
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.4.3 Command code values
|
The present document does not assign command code values but uses existing command defined by 3GPP and IETF.
|
9c251a86380319ca5f337310fb41e781
|
183 017
|
7.4.4 Application-ID value
|
The present document re-uses the value 16777222 allocated by IANA to the 3GPP Gq interface application. ETSI ETSI TS 183 017 V3.2.1 (2010-02) 33 Annex A (normative): Support for SIP forking A.1 Support for SIP forking The P-CSCF shall be able to handle forking. A.1.1 Authorization of resources for early media for forked responses When a SIP session has been originated by a connected UE, the P-CSCF may receive multiple provisional responses due to forking before the first final answer is received. The UE and the P-CSCF become aware of the forking only when the second provisional response arrives. For this, and any subsequent provisional response, the P-CSCF shall use an AA request within the existing Diameter session containing the SIP-Forking-Indication AVP with value SEVERAL_DIALOGUES and include the service information derived from the latest provisional response. When receiving an AA request containing the SIP-Forking-Indication AVP with value SEVERAL_DIALOGUES, the SPDF shall identify the existing authorization information for that Diameter session. The SPDF shall authorize any additional media components and any increased QoS requirements for the previously authorized media components, as requested within the service information. The SPDF shall authorize the maximum bandwidth required by any of the dialogues, but not the sum of the bandwidths required by all dialogues. Thus, the QoS authorized for a media component is equal to the highest QoS requested for that media component by any of the forked responses. The SPDF shall also send additional packet classifiers as required by the Flow Description AVPs within the session information to the BGF and A-RACF. A.1.2 Updating the authorization information at the final answer The P-CSCF shall store the SDP information for each early dialogue separately till the first final SIP answer is received. Then the related early dialogue is progressed to an established dialogue to establish the final SIP session. All the other early dialogues are terminated. The authorization information for the SIP session is updated to match the requirements of the remaining early dialogue only. When receiving the first final SIP response, the P-CSCF shall send an AA request without the SIP-Forking-Indication AVP and include the service information derived from the SDP corresponding to the dialogue of the final response. When receiving an AA request with no SIP-Forking-Indication AVP or with a SIP-Forking-Indication AVP with value SINGLE_DIALOGUE, the SPDF shall. update authorization information and packet classifiers to match only the requirements of the service information within this AA request. ETSI ETSI TS 183 017 V3.2.1 (2010-02) 34 Annex B (normative): QoS parameter mapping for IMS for unicast flows Within the IMS, session establishment and modification involves an end-to-end message-exchange using SIP/SDP with negotiation of media attributes (e.g. codecs) as defined in ES 283 003 [7]. The P-CSCF shall provide service information derived from the relevant SDP information to the SPDF via the Gq' interface. The P-CSCF shall apply the mapping rules in this annex to derive service information from SDP. B.1 SDP to service information mapping in AF The mapping described in this clause is mandatory for the P-CSCF and should also be applied by other AFs if the SDI is SDP. When a session is initiated or modified the P-CSCF shall use the mapping rules in table B.1.1 for each SDP media component to derive a Media-Component-Description AVP from the SDP Parameters. Furthermore, the P-CSCF shall map information about the grouping of media lines into resource reservation flows into the Flow-Grouping AVP as specified in table B.1.3. Table B.1.1: Rules for derivation of service information within Media-Component-Description AVP from SDP media component Service information per Media-Component-Description AVP (see notes 1 and 7) Derivation from SDP Parameters (see note 2) Media-Component-Number ordinal number of the position of the "m=" line in the SDP AF-Application-Identifier The AF-Application-Identifier AVP may be supplied or omitted, depending on the application. For IMS, if the AF-Application-Identifier AVP is supplied, its value should not demand application specific bandwidth or QoS class handling. However, if an IMS application is capable of handling a QoS downgrading, the AF-Application-Identifier AVP may be used to demand application specific bandwidth or QoS class handling. Media-Type The Media Type AVP shall be included with the same value as supplied for the media type in the "m=" line. Flow-Status IF port in m-line = 0 THEN Flow-Status:= REMOVED; ELSE IF the received SDP is SDP Offer and it requests session modification THEN IF Media-Component-Number exists THEN IF any SDI is different from existing one THEN Flow-Status :=DISABLED; ELSE Flow-Status is set to the same value of the existing media component; ENDIF ELSE Flow-Status :=DISABLED; ENDIF EXIT (NOTE 9) ELSE IF a=recvonly THEN IF <SDP direction> = mobile originated THEN Flow-Status := ENABLED_DOWNLINK; (NOTE 4) ELSE /* mobile terminated */ Flow-Status := ENABLED_UPLINK; (NOTE 4) ENDIF; ELSE IF a=sendonly THEN IF <SDP direction> = mobile originated THEN Flow-Status := ENABLED_UPLINK; (NOTE 4) ELSE /* mobile terminated */ Flow-Status := ENABLED_DOWNLINK; (NOTE 4) ENDIF; ELSE IF a=inactive THEN Flow-Status :=DISABLED; ETSI ETSI TS 183 017 V3.2.1 (2010-02) 35 Service information per Media-Component-Description AVP (see notes 1 and 7) Derivation from SDP Parameters (see note 2) ELSE /* a=sendrecv or no direction attribute */ Flow-Status := ENABLED (NOTE 4) ENDIF; ENDIF; ENDIF; ENDIF; (NOTE 5) Max-Requested-Bandwidth-UL IF <SDP direction> = mobile terminated THEN IF b=AS:<bandwidth> is present THEN Max-Requested-Bandwidth-UL:= <bandwidth> * 1000; /* Unit is bit/s ELSE Max-Requested-Bandwidth-UL:= <Operator specific setting>, or AVP not supplied; ENDIF; ELSE Consider SDP in opposite direction ENDIF (Note 8) Max-Requested-Bandwidth-DL IF <SDP direction> = mobile originated THEN IF b=AS:<bandwidth> is present THEN Max-Requested-Bandwidth-DL:= <bandwidth> * 1000; /* Unit is bit/s ELSE Max-Requested-Bandwidth-DL:= <Operator specific setting>, or AVP not supplied; ENDIF; ELSE Consider SDP in opposite direction ENDIF (Note8) RR-Bandwidth IF b=RR:<bandwidth> is present THEN RR-Bandwidth:= <bandwidth>; ELSE AVP not supplied ENDIF; (NOTE 3; NOTE 6) RS-Bandwidth IF b=RS:<bandwidth> is present THEN RS-Bandwidth:= <bandwidth>; ELSE AVP not supplied ENDIF; (NOTE 3: NOTE 6) Media-Sub-Component Supply one AVP for each Flow Identifier within the media component. The Flow identifiers are derived according to annex D of TS 129 207 [12]. The encoding of the AVP is described in table B.1.2. NOTE 1: The encoding of the service information is defined in the present document. NOTE 2: The SDP parameters are described in RFC 4566 [9]. NOTE 3: The "b=RS:" and "b=RR:" SDP bandwidth modifiers are defined in RFC 3556 [16]. NOTE 4: As an operator policy to disable forward and/or backward early media, the Flow-Status may be downgraded before a SIP dialogue is established, i.e. until a 200 OK(INVITE) is received. The Value "DISABLED" may be used instead of the Values "ENABLED_UPLINK" or "ENABLED_DOWNLINK". The Values "DISABLED", "ENABLED_UPLINK" or "ENABLED_DOWNLINK" may be used instead of the Value "ENABLED". NOTE 5: If the SDP answer is available when the session information is derived, the direction attributes and port number from the SDP answer shall be used to derive the flow status. However, to enable interoperability with SIP clients that do not understand the inactive SDP attribute, if a=inactive was supplied in the SDP offer, this shall be used to derive the flow status. If the SDP answer is not available when the session information is derived, the direction attributes from the SDP offer shall be used. NOTE 6: Information from the SDP answer is applicable, if available. NOTE 7: The AVPs may be omitted if they have been supplied in previous service information and have not changed. NOTE 8: TS 183 048 [21] provides rules to be used by the P-CSCF in deriving the bandwidth to request from RACS in the case an operator specific setting is to be used to populate the Max Requested Bandwidth DL and the Max-Requested-Bandwidth-UL AVPs. NOTE 9: Modifying existing media components with the SDP answer pending requires to set the FlowStatus to "DISABLED" as described in section 5.1.2. Depending on the SDP answer the updated or the old Media - Component -Description gets enabled using the procedure described below. ETSI ETSI TS 183 017 V3.2.1 (2010-02) 36 Table B.1.2: Rules for derivation of Media-Sub-Component AVP from SDP media component Gq' service information per Media-Sub-Component AVP (see notes 1 and 5) Derivation from SDP Parameters (see note 2) Flow-Number derived according to annex C of TS 129 207 [12] Flow-Status AVP not supplied Max-Requested-Bandwidth-UL AVP not supplied Max-Requested-Bandwidth-DL AVP not supplied Flow-Description For uplink and downlink direction, a Flow-Description AVP shall be provided unless no IP Flows in this direction are described within the media component. The SDP direction attribute (note 4) indicates the direction of the media IP flows within the media component as follows: IF a=recvonly THEN (NOTE 3) IF <SDP direction> = mobile originated THEN Provide only downlink Flow-Description AVP ELSE /* mobile terminated */ Provide only uplink Flow-Description AVP ENDIF; ELSE IF a=sendonly THEN (NOTE 3) IF <SDP direction> = mobile originated THEN Provide only uplink Flow-Description AVP ELSE /* mobile terminated */ Provide only downlink Flow-Description AVP ENDIF; ELSE /* a=sendrecv or a=inactive or no direction attribute */ Provide uplink and downlink Flow-Description AVPs ENDIF; ENDIF; For RTCP IP flows uplink and downlink Flow-Description AVPs shall be provided irrespective of the SDP direction attribute. The uplink destination address shall be copied from the "c=" line of downlink SDP (note 6). The uplink destination port shall be derived from the "m=" line of downlink SDP (note 6). The downlink destination address shall be copied from the "c=" line of uplink SDP (note 6). The downlink destination port shall be derived from the "m=" line of uplink SDP (note 6). Uplink and downlink source addresses shall either be derived from the prefix of the destination address or be wildcarded by setting to "any", as specified in the present document. Source ports shall not be supplied. Proto shall be derived from the transport of the "m=" line. For "RTP/AVP" proto is 17(UDP). Flow-Usage The Flow-Usage AVP shall be supplied with value "RTCP" if the IP flow(s) described in the Media-Sub-Component AVP are used to transport RTCP. Otherwise the Flow-Usage AVP shall not be supplied. [10] specifies how RTCP flows are described within SDP. NOTE 1: The encoding of the service information is defined in the present document. NOTE 2: The SDP parameters are described in [9]. NOTE 3: If the SDP direction attribute for the media component negotiated in a previous offer-answer exchange was sendrecv, or if no direction attribute was provided, and the new SDP direction attribute sendonly or recvonly is negotiated in a subsequent SDP offer-answer exchange, uplink and downlink Flow-Description AVPs shall be supplied. NOTE 4: If the SDP answer is available when the session information is derived, the direction attributes from the SDP answer shall be used to derive the flow description. However, to enable interoperability with SIP clients that do not understand the inactive SDP attribute, if a=inactive was supplied in the SDP offer, this shall be used. If the SDP answer is not available when the session information is derived, the direction attributes from the SDP offer shall be used. NOTE 5: The AVPs may be omitted if they have been supplied in previous service information and have not changed, as detailed in the present document. NOTE 6: If the session information is derived from an SDP offer, the required SDP may not yet be available. The corresponding Flow Description AVP shall nevertheless be included and the unavailable fields (possibly all) shall be wildcarded. ETSI ETSI TS 183 017 V3.2.1 (2010-02) 37 Table B.1.3: Rules for mapping SDP information about the grouping of media lines into resource reservation flows into the Flow Grouping AVP Flow-Grouping AVP (see note 1) Derivation from SDP Parameters (see note 2) Flow Grouping For each SDP "a=group:SRF" SDP line, a Flow Grouping AVP shall be generated (note 3). Flows For each identification tag within "a=group:SRF" SDP line, a Flows AVP containing a Media-Component-Number AVP identifying the corresponding m-line shall be generated (note 3). No Flow-Number AVP shall be supplied within the Flows AVP. NOTE 1: The encoding of the service information is defined in the present document. NOTE 2: The SDP parameters are described in [9]. NOTE 3: The SDP "group" attribute is defined in RFC 3388 [17] The "SRF" semantics attribute within this grouping framework is defined in RFC 3524 [18]. ETSI ETSI TS 183 017 V3.2.1 (2010-02) 38 Annex C (normative): QoS parameter mapping for IMS for multicast flows This clause describes the mapping on Gq' of the SDP payload parameters when having multicast flows. The mapping is quite different from mapping for unicast flows since SDP offer is similar to SDP answer in term of connection addresses and m-lines description concerning multicast flows as defined in RFC 3264 [22]. The P-CSCF shall apply the mapping rules in this annex to derive service information from SDP. C.1 SDP to service information mapping in AF for the IMS with multicast flows The mapping described in this clause is mandatory for the P-CSCF and should also be applied by other AFs if the SDI is SDP. In the case of IMS with multicast flows, the following clause should apply. When a session is initiated or modified the P-CSCF shall use the mapping rules in table C.1.1 for each SDP media component to derive a Media-Component-Description AVP from the SDP Parameters. Table C.1.1: Rules for derivation of service information within Media-Component-Description AVP from SDP media component for multicast flows service information per Media-Component-Description AVP (see notes 1 and 7) Derivation from SDP Parameters (see note 2) Media-Component-Number ordinal number of the position of the "m=" line in the SDP. AF-Application-Identifier The AF-Application-Identifier AVP may be supplied or omitted, depending on the application. For IMS, if the AF-Application-Identifier AVP is supplied, its value should not demand application specific bandwidth or QoS class handling. However, if an IMS application is capable of handling a QoS downgrading, the AF-Application-Identifier AVP may be used to demand application specific bandwidth or QoS class handling. Media-Type The Media Type AVP shall be included with the same value as supplied for the media type in the "m=" line. Flow-Status IF port in m-line = 0 THEN Flow-Status:= REMOVED; ELSE ( IF <SDP direction> = UE originated THEN (IF a=recvonly THEN Flow-Status := ENABLED_DOWNLINK; (NOTE 4) ELSE (IF a=sendonly THEN Flow-Status := ENABLED UPLINK; (NOTE 4) ELSE Flow-Status :=DISABLED; ENDIF;) ENDIF;) ELSE (UE terminated) (IF a=recvonly THEN Flow-Status := ENABLED_UPLINK; (NOTE 4) ELSE (IF a=sendonly THEN Flow-Status := ENABLED DOWNLINK; (NOTE 4) ELSE Flow-Status :=DISABLED; ENDIF;) ENDIF;) ENDIF;) ENDIF; (Note 5) ETSI ETSI TS 183 017 V3.2.1 (2010-02) 39 service information per Media-Component-Description AVP (see notes 1 and 7) Derivation from SDP Parameters (see note 2) Max-Requested-Bandwidth-UL IF a= sendonly THEN IF b=AS:<bandwidth> is present THEN Max-Requested-Bandwidth-UL:= <bandwidth> * 1000; /* Unit is bit/s ELSE Max-Requested-Bandwidth-UL:= <Operator specific setting>, or AVP not supplied; ENDIF; ELSE Max-Requested-Bandwidth-UL:=0 ENDIF (Note 8) Max-Requested-Bandwidth-DL IF a=recvonly THEN IF b=AS:<bandwidth> is present THEN Max-Requested-Bandwidth-DL:= <bandwidth> * 1000; /* Unit is bit/s ELSE Max-Requested-Bandwidth-DL:= <Operator specific setting>, or AVP not supplied; ENDIF; ELSE Max-Requested-Bandwidth-DL:=0 ENDIF (Note 8) RR-Bandwidth AVP NOT SUPPLIED RS-Bandwidth IF b=RS:<bandwidth> is present THEN RS-Bandwidth:= <bandwidth>; ELSE AVP not supplied ENDIF; (NOTE 3; NOTE 6) Media-Sub-Component Supply one AVP for each Flow Identifier within the media component. The Flow identifiers are derived according to annex D of TS 129 207 [12]. The encoding of the AVP is described in table C.1.2. Media-Authorization-Context-Id IF a=bc_service_package: <mult_list> is present THEN AVP not supplied; ELSE IF a=bc_service_package: <BCPackageId> is present THEN Media-Authorization-Context-Id:= <BCPackageId>; ELSE AVP not supplied; ENDIF; ENDIF; (NOTE 9; NOTE 10) NOTE 1: The encoding of the service information is defined in the present document. NOTE 2: The SDP parameters are described in RFC 4566 [9]. NOTE 3: The "b=RS:" and "b=RR:" SDP bandwidth modifiers are defined in RFC 3556 [16]. NOTE 4: As an operator policy to disable forward and/or backward early media, the Flow-Status may be downgraded before a SIP dialogue is established, i.e. until a 200 OK(INVITE) is received. The Value "DISABLED" may be used instead of the Values "ENABLED_UPLINK" or "ENABLED_DOWNLINK". The Values "DISABLED", "ENABLED_UPLINK" or "ENABLED_DOWNLINK" may be used instead of the Value "ENABLED". NOTE 5: If the SDP answer is available when the session information is derived, the direction attributes and port number from the SDP answer shall be used to derive the flow status. However, to enable interoperability with SIP clients that do not understand the inactive SDP attribute, if a=inactive was supplied in the SDP offer, this shall be used to derive the flow status. If the SDP answer is not available when the session information is derived, the direction attributes from the SDP offer shall be used. NOTE 6: Information from the SDP answer is applicable, if available. NOTE 7: The AVPs may be omitted if they have been supplied in previous service information and have not changed. NOTE 8: TS 183 048 [21] provides rules to be used by the P-CSCF in deriving the bandwidth to request from RACS in the case an operator specific setting is to be used to populate the Max Requested Bandwidth DL and the Max-Requested-Bandwidth-UL AVPs. NOTE 9: Information from the SDP answer is applicable, if available. NOTE 10: The "a=bc_service_package:" modifier is defined in TS 183 063 [20]. ETSI ETSI TS 183 017 V3.2.1 (2010-02) 40 Table C.1.2: Rules for derivation of Media-Sub-Component AVP from SDP media component for IMS Multicast flows Gq' service information per Media-Sub-Component AVP (note 1, note 2) Derivation from SDP Parameters (see note 2) Flow-Number derived according to annex C of TS 129 207 [12] Flow-Status The flow-status shall be identical to the one defined at media-component level. Max-Requested-Bandwidth-UL AVP NOT SUPPLIED Max-Requested-Bandwidth-DL AVP NOT SUPPLIED Flow-Description The SDP direction attribute indicates the direction of the media IP flows within the media component as follows: IF a=recvonly THEN (NOTE 3) Provide only downlink Flow-Description AVP ELSE IF a=sendonly THEN (NOTE 1) Provide only uplink Flow-Description AVP ENDIF; The downlink or uplink destination addresses shall be copied from the "c=" line in the SDP. The downlink or uplink destination port shall be derived from the "m=" line in the SDP. Uplink and downlink source addresses shall be set to "any", as specified in the present document. Source ports shall not be supplied. Flow-Usage AVP not supplied NOTE 1: When the bc_service_package: attribute is present in the SDP and contains a multicast list, the table C.1.3 applies for flow description. NOTE 2: The AVPs may be omitted if they have been supplied in previous service information and have not changed. When a bc_service package: attribute is received in the SDP and includes a multicast list, table C.1.2 applies with the following exceptions: - The AF shall include a Media-Sub-Component corresponding to each of the elements in the multicast list. - Flow-status shall be set to REMOVED when the request concerns a session modification and the flow is not part of the multicast list anymore. Table C.1.3: Rules for derivation of Media-Sub-Component AVP from multicast list parameter in service package id Flow-Description IF source address in the mult_list parameters is present THEN source address = downlink source address Else source address is set to "any" Downlink multicast address shall be set to the multicast address in the multicast address unit ENDIF; Source and destination ports shall not be supplied. ETSI ETSI TS 183 017 V3.2.1 (2010-02) 41 Annex D (informative): Bibliography ETSI TS 182 006: "Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); IP Multimedia Subsystem (IMS); Stage 2 description (3GPP TS 23.228 v7.2.0, modified)". ETSI ETSI TS 183 017 V3.2.1 (2010-02) 42 Annex E (informative): Change history Date WG Doc. CR Rev CAT Title / Comment Current Version New Version 10-06-09 21WTD081r1 001 F Start of NGN Rel-3 2.3.1 3.0.0 CR001 TB approved 2.3.1 3.0.0 21-08-09 21bTD092r1 002 B Clarification of the value of the Flow Status AVP 3.0.0 3.0.1 21-08-09 21bTD095r1 003 F Update of the Reservation priority AVP 3.0.0 3.0.1 Insertion of change history table 3.0.1 3.0.2 CRs 002 and 003 TB approved at TISPAN#22 3.0.2 3.1.0 06-11-09 22bTD065r1 004 F AF-Application-Id alignment with 29.209 3.1.0 3.1.1 06-11-09 22bTD078r3 005 B Multicast notification support 3.1.0 3.1.1 15-12-09 23WTD091r1 006 B Add Destination-Host AVP to Gq' 3.1.1 3.1.2 CRs 004 to 006 TB approved at TISPAN#23 and publication 3.1.2 3.2.1 ETSI ETSI TS 183 017 V3.2.1 (2010-02) 43 History Document history V1.1.1 March 2006 Publication V1.4.0 August 2007 Publication V2.3.1 September 2008 Publication V3.2.1 February 2010 Publication
|
93f9caba3d6ecf53b01bf36429d3bf8e
|
182 023
|
1 Scope
|
The present document provides the possible scenarios for: • the interconnection of an Next Generation Corporate Network (NGCN) with a Next Generation Network (NGN); and • the support of NGCN capabilities within an NGN, either towards a User Equipment (UE) or to an NGCN. Unless otherwise specified by reference to other documents, all requirements relating to architecture and functional requirements are contained within the present document. The structure of the present document reflects the historical structure of previous versions of it. All references to ETSI TS 124 523 [8] are intended to be to the entire contents of the referenced document, which now forms the contents of the present document, and not to any part which might be implied by any headings within the present document.
|
93f9caba3d6ecf53b01bf36429d3bf8e
|
182 023
|
2 References
| |
93f9caba3d6ecf53b01bf36429d3bf8e
|
182 023
|
2.1 Normative references
|
References are either specific (identified by date of publication and/or edition number or version number) or non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the reference document (including any amendments) applies. Referenced documents which are not found to be publicly available in the expected location might be found at http://docbox.etsi.org/Reference. NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee their long term validity. The following referenced documents are necessary for the application of the present document. [1] Void. [2] Void. [3] Void. [4] Void. [5] Void. [6] Void. [7] Void. [8] ETSI TS 124 523: "Universal Mobile Telecommunications System (UMTS); LTE; Core and enterprise Next Generation Network (NGN) interaction scenarios; Architecture and functional description (3GPP TS 24.523)".
|
93f9caba3d6ecf53b01bf36429d3bf8e
|
182 023
|
2.2 Informative references
|
References are either specific (identified by date of publication and/or edition number or version number) or non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the reference document (including any amendments) applies. NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee their long term validity. ETSI ETSI TS 182 023 V3.0.0 (2015-11) 6 The following referenced documents are not necessary for the application of the present document but they assist the user with regard to a particular subject area. Not applicable.
|
93f9caba3d6ecf53b01bf36429d3bf8e
|
182 023
|
3 Definitions and abbreviations
| |
93f9caba3d6ecf53b01bf36429d3bf8e
|
182 023
|
3.1 Definitions
|
For the purposes of the present document, the terms and definitions given in ETSI TS 124 523 [8] apply.
|
93f9caba3d6ecf53b01bf36429d3bf8e
|
182 023
|
3.2 Abbreviations
|
For the purposes of the present document, the terms and definitions given in ETSI TS 124 523 [8] apply.
|
93f9caba3d6ecf53b01bf36429d3bf8e
|
182 023
|
4 Introduction
|
The provisions of the present document are contained in ETSI TS 124 523 [8].
|
93f9caba3d6ecf53b01bf36429d3bf8e
|
182 023
|
5 General requirements
|
The provisions of the present document are contained in ETSI TS 124 523 [8]. 6 Scenarios relating to a level of service of IP connectivity The provisions of the present document are contained in ETSI TS 124 523 [8]. 7 Scenarios relating to a level of service of session establishment and control of communication session The provisions of the present document are contained in ETSI TS 124 523 [8]. 8 Scenarios relating to a level of service of application level The provisions of the present document are contained in ETSI TS 124 523 [8].
|
93f9caba3d6ecf53b01bf36429d3bf8e
|
182 023
|
9 Scenarios relating to roaming
|
The provisions of the present document are contained in ETSI TS 124 523 [8]. ETSI ETSI TS 182 023 V3.0.0 (2015-11) 7 Annex A (informative): Change history Date WG Doc. CR Rev CAT Title / Comment Current Version New Version 3/09/2015 NTECH(15) 12_004 001 D Alignment with 3GPP TS 24.523 2.1.1 3.0.0 ETSI ETSI TS 182 023 V3.0.0 (2015-11) 8 History Document history V2.1.1 January 2009 Publication V3.0.0 November 2015 Publication
|
83fb431f48ecf1b90224c947495fb807
|
183 004
|
1 Scope
|
The present document specifies the, stage three, Protocol Description of the Communications Diversion (CDIV) services.
|
83fb431f48ecf1b90224c947495fb807
|
183 004
|
2 References
|
References are either specific (identified by date of publication and/or edition number or version number) or non-specific. • For a specific reference, subsequent revisions do not apply. • Non-specific reference may be made only to a complete document or a part thereof and only in the following cases: - if it is accepted that it will be possible to use all future changes of the referenced document for the purposes of the referring document; - for informative references. Referenced documents which are not found to be publicly available in the expected location might be found at http://docbox.etsi.org/Reference. For online referenced documents, information sufficient to identify and locate the source shall be provided. Preferably, the primary source of the referenced document should be cited, in order to ensure traceability. Furthermore, the reference should, as far as possible, remain valid for the expected life of the document. The reference shall include the method of access to the referenced document and the full network address, with the same punctuation and use of upper case and lower case letters. NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee their long term validity.
|
83fb431f48ecf1b90224c947495fb807
|
183 004
|
2.1 Normative references
|
The following referenced documents are indispensable for the application of the present document. For dated references, only the edition cited applies. For non-specific references, the latest edition of the referenced document (including any amendments) applies. [1] Void. [2] Void. [3] Void. [4] Void. [5] Void. [6] Void. [7] Void. [8] Void. [9] Void. [10] Void. [11] Void. [12] Void. ETSI ETSI TS 183 004 V2.5.0 (2008-06) 6 [13] Void. [14] Void. [15] Void. [16] Void. [17] Void. [18] Void. [19] ETSI TS 124 504: "Digital cellular telecommunications system (Phase 2+); Universal Mobile Telecommunications System (UMTS); TISPAN; PSTN/ISDN simulation services: Communication Diversion (CDIV); Protocol specification (Release 8)".
|
83fb431f48ecf1b90224c947495fb807
|
183 004
|
2.2 Informative references
|
The following referenced documents are not essential to the use of the present document but they assist the user with regard to a particular subject area. For non-specific references, the latest version of the referenced document (including any amendments) applies. Not applicable.
|
83fb431f48ecf1b90224c947495fb807
|
183 004
|
3 Definitions and abbreviations
| |
83fb431f48ecf1b90224c947495fb807
|
183 004
|
3.1 Definitions
|
For the purposes of the present document, the terms and definitions given in TS 124 504 [19] apply.
|
83fb431f48ecf1b90224c947495fb807
|
183 004
|
3.2 Abbreviations
|
For the purposes of the present document, the abbreviations given in TS 124 504 [19] apply.
|
83fb431f48ecf1b90224c947495fb807
|
183 004
|
4 Communications Diversion (CDIV)
|
The provisions of the present document are contained in TS 124 504 [19]. ETSI ETSI TS 183 004 V2.5.0 (2008-06) 7 Annex A (informative): Signalling Flows Information is contained in TS 124 504 [19]. ETSI ETSI TS 183 004 V2.5.0 (2008-06) 8 Annex B (informative): Example of filter criteria Information is contained in TS 124 504 [19]. ETSI ETSI TS 183 004 V2.5.0 (2008-06) 9 Annex C (informative): Coding considerations Information is contained in TS 124 504 [19]. ETSI ETSI TS 183 004 V2.5.0 (2008-06) 10 Annex D (informative): Bibliography Information is contained in TS 124 504 [19]. ETSI ETSI TS 183 004 V2.5.0 (2008-06) 11 Annex E (informative): Change history Information is contained in TS 124 504 [19]. ETSI ETSI TS 183 004 V2.5.0 (2008-06) 12 History Document history V2.4.0 January 2008 Publication V2.5.0 June 2008 Publication
|
ab1c63542674cc1bca784b5679b06cff
|
182 018
|
1 Scope
|
The present document describes the specific TISPAN requirements for controls to manage overload of processing resources in NGNs. In particular, it addresses overload control between nearest neighbours.
|
ab1c63542674cc1bca784b5679b06cff
|
182 018
|
2 References
|
References are either specific (identified by date of publication and/or edition number or version number) or non-specific. • For a specific reference, subsequent revisions do not apply. • Non-specific reference may be made only to a complete document or a part thereof and only in the following cases: - if it is accepted that it will be possible to use all future changes of the referenced document for the purposes of the referring document; - for informative references. Referenced documents which are not found to be publicly available in the expected location might be found at http://docbox.etsi.org/Reference. For online referenced documents, information sufficient to identify and locate the source shall be provided. Preferably, the primary source of the referenced document should be cited, in order to ensure traceability. Furthermore, the reference should, as far as possible, remain valid for the expected life of the document. The reference shall include the method of access to the referenced document and the full network address, with the same punctuation and use of upper case and lower case letters. NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee their long term validity.
|
ab1c63542674cc1bca784b5679b06cff
|
182 018
|
2.1 Normative references
|
The following referenced documents are indispensable for the application of the present document. For dated references, only the edition cited applies. For non-specific references, the latest edition of the referenced document (including any amendments) applies. [1] ITU-T recommendation E.412: "Network management controls". [2] ETSI TR 182 015: "Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); Next Generation Networks; Architecture for Control of Processing Overload". [3] ETSI ES 282 003: " Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); Resource and Admission Control Sub-system (RACS); Functional Architecture". [4] ETSI TS 181 005 V2.4.0 (2007-11): "Telecommunications and Internet Converged Services and Protocols for Advanced Networking (TISPAN); Service and Capability Requirements".
|
ab1c63542674cc1bca784b5679b06cff
|
182 018
|
3 Abbreviations
|
For the purposes of the present document, the following abbreviations apply: IMS IP Multimedia Subsystem ISDN Integrated Service Digital Network NGN Next Generation Network ETSI ETSI TS 182 018 V2.0.0 (2008-01) 6 PSTN Public Switched Telecommunication Network QoS Quality of Service RACS Resource Admission Subsystem SCF Session Control Function SIP Session Initiation Protocol SLA Service Level Agreement
|
ab1c63542674cc1bca784b5679b06cff
|
182 018
|
4 TISPAN NGN overload control requirements
| |
ab1c63542674cc1bca784b5679b06cff
|
182 018
|
4.1 High level overload control requirements
|
In TS 181 005 [4] we have the following requirements for overload control. The NGN shall have mechanisms available to control overload that: 1) automatically maximize effective throughput (i.e. admitted service requests/sec) at an overloaded resource; 2) achieve this throughout the duration of an overload event, and irrespective of the overloaded resource's capacity or of the number of sources of overload; 3) are configurable by the service provider so that, under processing overload, a high proportion of response times at overloaded resources are low enough so as not to cause customers to prematurely abandon service requests; 4) should be possible to be applied within a service provider's NGN, and between different service providers' NGNs; 5) should be possible to be applied within an NGN subsystem (e.g. IMS, PSTN/ISDN emulation) and between different NGN subsystems. NOTE: As a general rule, an NGN's call, session and command processing resources can experience prolonged processing overload under the appropriate circumstances (e.g. partial, or full, server failure, high rates of incoming service requests). Consequently, it needs to be equipped with some form of overload detection and control (including expansive controls such as load balancing and resource replication), in order to keep response times just low enough under such processing overload to preclude customers abandoning their service requests prematurely. Many pieces of equipment will have internal load control, which aims to meet the ideal behaviour described in ITU-T recommendation E.412 [1] and shown graphically in figure 1. The object of these internal controls is to bound the system response time by rejecting some of the workload (because rejecting workload requires less effort than accepting it). As the load increases requests are rejected, but because the rejected requests still consume some processing resource, the rate at which requests can be accepted falls. As a consequence, such internal load control can only protect the physical host against overload to a limited extent. Severe overloads will reduce the rate at which useful work can be done, and very severe overloads may cause the system to operate incorrectly or with unacceptably long response times. ETSI ETSI TS 182 018 V2.0.0 (2008-01) 7 Figure 1: hedoo Typical overload behaviour in a host with internal load control. By deploying a distributed overload control, in which systems suppress some service requests before they reach an overloaded neighbour, the overloaded system is protected from more extreme overloads thus enabling it to operate at near optimum load. For the fulfilment of these NGN requirements, the use of such nearest neighbour overload controls an essential component. The issues regarding overload controls for NGNs have been discussed at some length in [2] which provides some initial requirements for overload controls. These requirements are further elaborated in the present document and allocated into different categories. The requirements are also extended to cover the case where an overloaded target has a non-enumerable set of sources (e.g. SIP user agents overloading an SCF) The overload control requirements for systems loaded by a set of non-enumerable sources may be similar to those for a source loaded by a known, enumerable set of sources, but the approach may be very different. In the enumerable sources case, we may want to control the relative performance seen by each source, offer SLAs to particular sources and have a variety of fairness criteria to use. In the non-enumerable sources case, the issue is one of reducing the aggregate demand, and the fate of individual sources is less predictable. The definition of fairness would perhaps depend on ensuring equitable treatment over a series of overloads, rather than trying to meet fairness criteria between many sources over a single overload event. Those requirements that are not appropriate for non-enumerable sources are labelled as such.
|
ab1c63542674cc1bca784b5679b06cff
|
182 018
|
4.2 General requirements for Nearest Neighbour load control
|
These requirements are general, and any overload control should address these requirements. REQ 1 A control shall automatically reduce the load that is sent to an overloaded host. REQ 2 A control shall aim to maximize the number of fully processed service requests at an overloaded host, subject to meeting any QoS constraints for the application (e.g. response times). REQ 3 The overload control restriction shall apply only to defined events which will depend on the reference point that is being controlled. NOTE 1: This information may be thought of as within the domain of the applications on the NGN servers. It is the application that "knows" which requests to offer to the control for possible rejection, the control provides the infrastructure for the restriction to occur. REQ 4 A control shall be aware of differing importance levels of service requests, and be configurable to reject lower importance service requests in favour of service requests of higher importance level (for example to protect calls to emergency services). REQ 5 When several inter-acting controls are active at an overloaded host at the same time, they shall converge to an acceptable steady-state when the amount of work sent by each of the sources is constant. REQ 6 A control shall be configurable by the service provider to enable the enforcement of SLAs i.e. to divide the capacity of an overloaded resource between hosts from which requests are received (or groups of hosts) according to agreed policies. NOTE 2: It is inappropriate to attempt to manage SLAs for individual sources from a set of non-enumerable sources. ETSI ETSI TS 182 018 V2.0.0 (2008-01) 8 REQ 7 A control shall enforce fair allocation of overloaded processing resources between competing request sources (a request source in this context means the host from which the overloaded resource receives the request, not necessarily the originating host). NOTE 3: It is the SLA that defines the resources allocated to a request source by an overloaded resource. A fair allocation of resources implies that the resource consumed by every source is appropriate given the SLA allocated to that source. It does not necessarily require that the each request source obtains the same amount of processing resource. REQ 8 The behaviour of the control shall be fully-specified. REQ 9 A control shall allow manual configuration of the overload control's components via a management interface. REQ 10 A control shall operate (optionally) without manual configuration of the overload control parameters. REQ 11 A control shall output network management data on event occurrence (e.g. control activation/termination) and on demand from network management (e.g. counts of service requests admitted and rejected by the overload control). REQ 12 A control shall have adequate security from malicious actions. It shall not be possible for a host to instantiate a restriction able to reject service requests destined for a different host. NOTE 4: This implies that a mechanism for the verification of the identity of hosts originating restriction messages is required. REQ 13 A control shall be applicable within a network, and between networks. REQ 14 It should be possible to apply overload control between different NGN subsystems. REQ 15 A control shall react quickly to changes in the workload sent to the host it is protecting. REQ 16 A control shall be capable of dealing with work received from hosts which do not support it. Such hosts that are part of a finite set of sources shall not receive disproportionate benefit (i.e. requirements 6 and 7 shall still hold).
|
ab1c63542674cc1bca784b5679b06cff
|
182 018
|
4.3 Deployment specific requirements
|
The following requirements relate to different deployment options of the protected host and its traffic sources. Particular controls will need to address these deployments, so any overload control architecture must support or enable these requirements. REQ 17 Controls are required for scenarios where hosts receive service requests from an uncountable number of unknown sources as well as scenarios where hosts receive service requests from a known set of sources. A particular overload target may have a mixture of known, enumerable sources as well as an unknown, non-enumerable set of sources. In those cases, it shall be possible for the controls to inter-work, such that the SLAs for the enumerable sources are protected and the non-enumerable sources are managed on the basis of the aggregate workload from them all. REQ 18 A control shall inter-work with proxies, load balancing and load forking.
|
ab1c63542674cc1bca784b5679b06cff
|
182 018
|
4.4 Application specific requirements
|
The general requirements above relate to overload controls that act between hosts that are nearest neighbours, i.e. host load control. Application specific requirements arise from the need for some applications to perform functions closely related to host load control. Many of these requirements are not naturally part of host load control, as they are specific to a particular protocol/application, but they may be implemented by an application using the basic infrastructure used for host overload control. An important feature of these application level controls is that they have an application defined granularity, whereas host load control only distinguished between flows on the basis of the host from which the request is received. ETSI ETSI TS 182 018 V2.0.0 (2008-01) 9 REQ 19 A control shall enforce fair allocation of an overloaded processing resource between competing controlled application layer level streams of service requests, where such streams need not have a 1:1 correspondence to nearest neighbour hosts. REQ 20 A control shall be configurable by the service provider to enable the enforcement of SLAs for application level flows (to divide the capacity of an overloaded resource between competing application level requests flows according to agreed policies). This would allow a service provider to use the nearest neighbour load control infrastructure to protect well behaved flows when processing congestion is being caused by "badly behaved" flows, even though those flows are from the same nearest neighbour. REQ 21 A control shall facilitate an application to automatically limit ineffective service requests by detecting specific destination application layer names/addresses that are attracting a high reject rate and selectively controlling demand to them. ETSI ETSI TS 182 018 V2.0.0 (2008-01) 10 Annex A (informative): Comparison between RACS and nearest neighbour overload control The Resource Admission Control Sub-system (RACS) [3] is responsible for regulating access to NGN resources. Initially, one might think that nearest neighbour load control is simply a specific subset of the functionality of RACS as its role is to regulate access to computational resource. In that case, it might seem paradoxical that nearest neighbour load control is additional to the architecture while RACS is an integrated part of the architecture. The key to resolving this apparent paradox is to understand the fundamentally different objectives of the two. RACS is specifically designed to manage access to resources in the transport stratum that deliver service to end users, i.e. it regulates access to bandwidth to ensure the QoS targets of the user session are maintained. It is an integral part of the service delivery and is designed to allow end to end admission control to be achieved. The RACS infrastructure enables the resource for a particular end user session to be secured on an end to end basis before the session is admitted. Nearest neighbour load control, on the other hand, is not integrated into the service logic. There is no end to end co- ordination of the nearest neighbour load control admission decisions, they are all local (independent) decisions extending only as far as nearest neighbours - the admission decisions are not service based - nearest neighbour load control is not accepting or rejecting a user session rather it is accepting or rejecting the request processing on that particular node. To clearly demonstrate the difference, consider the fact that nearest neighbour load control may be deployed between servers that implement RACS. The differences between RACS and nearest neighbour load control are summarized in table 1. Table 1: A comparison between RACS and nearest neighbour load control RACS Nearest neighbour load control Request acceptance by RACS implies that resource is reserved for that request Acceptance of request by nearest neighbour load control does not imply a reservation of any processing resource Provides complex distributed functionality Only affects nearest neighbours Objective is service QoS control Objective is processing infrastructure protection May be a concrete instantiation - one can touch a physical system that only implements RACS functions Only exists as a component in physical systems that implement NGN functions ETSI ETSI TS 182 018 V2.0.0 (2008-01) 11 History Document history V2.0.0 January 2008 Publication
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
1 Scope
|
The present document describes an IMS-based functional architecture for the PSTN/ISDN Emulation Subsystem (PES) of the ETSI TISPAN NGN overall architecture. The IMS-based PSTN/ISDN Emulation Subsystem described herein supports the emulation of PSTN services for analog terminals and ISDN services for ISDN terminals and PBXs. These may be connected directly to residential gateways or access gateways, or via V5 access networks. The present document provides a framework for an IMS-based functional architecture and is considered to be a preliminary version. In addition, in order to fulfil the requirements of different operators and national regulatory requirements, this architecture will need to be enhanced. See annex A for a list of potential open areas.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
2 References
|
References are either specific (identified by date of publication and/or edition number or version number) or non-specific. • For a specific reference, subsequent revisions do not apply. • Non-specific reference may be made only to a complete document or a part thereof and only in the following cases: - if it is accepted that it will be possible to use all future changes of the referenced document for the purposes of the referring document; - for informative references. Referenced documents which are not found to be publicly available in the expected location might be found at http://docbox.etsi.org/Reference. For online referenced documents, information sufficient to identify and locate the source shall be provided. Preferably, the primary source of the referenced document should be cited, in order to ensure traceability. Furthermore, the reference should, as far as possible, remain valid for the expected life of the document. The reference shall include the method of access to the referenced document and the full network address, with the same punctuation and use of upper case and lower case letters. NOTE: While any hyperlinks included in this clause were valid at the time of publication ETSI cannot guarantee their long term validity.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
2.1 Normative references
|
The following referenced documents are indispensable for the application of the present document. For dated references, only the edition cited applies. For non-specific references, the latest edition of the referenced document (including any amendments) applies. [1] ETSI ES 282 001: "Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); NGN Functional Architecture Release 1". [2] ETSI ES 282 007: "Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); IP Multimedia Subsystem (IMS) Functional architecture". [3] ETSI TS 182 006: "Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); IP Multimedia Subsystem (IMS); Stage 2 description". [4] ETSI ES 283 003: "Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); IP Multimedia Call Control Protocol based on Session Initiation Protocol (SIP) and Session Description Protocol (SDP) Stage 3 [3GPP TS 24.229 [Release 7], modified]". ETSI ETSI TS 182 012 V2.1.4 (2008-03) 7 [5] ETSI TS 183 043: "Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); IMS-based PSTN/ISDN Emulation; Stage 3 specification". [6] ETSI TS 183 021: "Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); NGN Release 1; Endorsement of 3GPP TS 29.162 Interworking between IM CN Sub-system and IP networks". [7] ETSI ES 282 010: "Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); Charging management Endorsement of 3GPP TS 32.240 Release 7, 3GPP TS 32.260 Release 7, 3GPP TS 32.297 Release 7, 3GPP TS 32.298 Release 7 and 3GPP TS 32.299 Release 7, modified". [8] ETSI ES 201 915-1: "Open Service Access (OSA); Application Programming Interface (API); Part 1: Overview (Parlay 3)". [9] IETF RFC 3136: "The SPIRITS architecture". [10] ETSI ETS 300 738: "Human Factors (HF); Minimum Man-Machine Interface (MMI) to public network based supplementary services". [11] ITU-T Recommendation H.248: "Gateway control protocol". [12] ETSI EN 300 659 (all parts): "Access and Terminals (AT); Analogue access to the Public Switched Telephone Network (PSTN); Subscriber line protocol over the local loop for display (and related) services". [13] ETSI ETR 150: "V5 interface; Public Switched Telephone Network (PSTN) mappings".
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
2.2 Informative references
|
Not Applicable.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
3 Definitions and abbreviations
| |
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
3.1 Definitions
|
For the purposes of the present document, the following terms and definitions apply: Access Gateway (AG): gateway device that interworks a significant number of analogue lines/ISDN accesses (directly or via an V5 Access Network) to a packet network and is located at the operator's premises NOTE: An AG can take the form of a Media Gateway (A-MGW) or a Voice over IP Gateway (A-VGW). Media Gateway (MGW): gateway device acting at the media/transport plane, providing the functions of an MGF as defined in ES 282 001 [1] NOTE 1: A MGW may additionally relay signalling traffic, in which case it also provides the functions of an SGF as defined in ES 282 001 [1]. NOTE 2: In the present document, Media Gateway refers both to Access Gateways and to Residential Gateways, to form a A-MGW, or a R-MGW, respectively. Media Gateway Controller (MGC): See ITU-T Recommendation H.248 [11]. Residential Gateway (RG): gateway device that interworks a small number of analogue lines/ISDN accesses NOTE: A residential gateway typically contains one or two analogue lines/ISDN accesses and is located at the customer premises. A RG can take the form of a Media Gateway (R-MGW) or a Voice over IP Gateway (R-VGW). ETSI ETSI TS 182 012 V2.1.4 (2008-03) 8 Voice over IP Gateway (VGW): SIP-based gateway device that connects legacy equipment to the NGN NOTE 1: A Voice over IP Gateways (VGW) plays the role of an IMS UE with regards to the P-CSCF. NOTE 2: A Voice over IP Gateway can be classified as a AG or RG, to form a A-VGW, or a R-VGW, respectively.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
3.2 Abbreviations
|
For the purposes of the present document, the following abbreviations apply: AF Application Function AG Access Gateway AGCF Access Gateway Control Function A-MGF Access Media Gateway Function A-MGW Access Media GateWay AN Access Node AS Application Server ASF Application Server Function ATA Analogue Terminal Adaptor A-VGW Access Voice over IP GateWay BCSM Basic Call State Model BGCF Breakout Gateway Control Function BGF Border Gateway Function CCBS Call Completion on Busy Subscriber CSCF Call Session Control Function DDI Direct Dialling In DNS Domain Name Server DSS1 Digital Subscriber Signalling System No.1 GW GateWay HSS Home Subscriber Server IBCF Interconnection Border Control Function I-CSCF Interrogating-Call Session Control Function IM IP Multimedia IMS IP Multimedia Subsystem IM-SSF IP Multimedia-Service Switching Function ISDN Integrated Services Digital Network ISUP ISDN User Part IWF InterWorking Function MG Media Gateway MGC Media Gateway Controller MGCF Media Gateway Control Function MGF Media Gateway Function MGW Media Gateway MRFC Multimedia Resource Function Controller MRFP Multimedia Resource Function Processor NAPT Network Address Port Translation NASS Network Attachment SubSystem NGN Next Generation Network OSA Open Service Access PBX Private Branch Exchange P-CSCF Proxy-Call Session Control Function PES PSTN/ISDN Emulation Subsystem PSTN Public Switched Telephone Network RACS Resource and Admission Control Subsystem RG Residential Gateway R-MGF Residential-MGF R-MGW Residential Media GateWay R-VGW Residential Voice over IP GateWay SCIM Service Capability Interaction Manager SCS Service Capability Server S-CSCF Serving-Call Session Control Function ETSI ETSI TS 182 012 V2.1.4 (2008-03) 9 SIGTRAN SIGnalling TRANsport SIP Session Initiation Protocol SLF Subscription Locator Function SS7 Signalling System n°7 SSF Service Switching Function TDM Time Division Multiplexing TGW Trunking Gateway T-MGF Trunking Media Gateway Function UE User Equipment UPSF User Profile Server Function VGW Voice over IP GateWay VoIP Voice over IP
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
4 Overview
| |
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
4.1 PSTN/ISDN Emulation subsystem environment
|
Figure 1 shows the PSTN/ISDN Emulation Subsystem and its relationships with other TISPAN NGN subsystem. Applications/ User Profiles Resource and Admission Control Subsystem Residential and Access MGW TISPAN PSTN/ISDN Emulation Subsystem Core IMS PSTN/ISDN (TDM based) Network Attachment Subsystem Charging functions Network Management Functions Other MM Subsystems Residential and Access VGW Figure 1: PSTN/ISDN Emulation Subsystem and its environment
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
4.2 Signalling configurations
|
Figure 2 illustrates the signalling configurations supported by the PSTN/ISDN Emulation Subsystem (PES) described in the present document. PSTN/ISDN Emulation Subsystem ISDN/PSTN ISDN/PSTN Trunk Trunk T-MGF T-MGF V5.x AN analog access ISDN access V5.x AN analog access ISDN access MGW/ VGW MGW/ VGW Figure 2: Signalling Configurations ETSI ETSI TS 182 012 V2.1.4 (2008-03) 10 Legacy terminals, i.e. analog phones and ISDN phones may be connected to R-VGW, R-MGW, A-VGW and A-MGW, using the interfaces based on the Z, S/T and U reference point, respectively. ISDN PBXs may be connected to an A-VGW or A-MGW using the interfaces based on the T reference point. When connected to an AG (A-VGW or A-MGW) a legacy terminal or ISDN PBX may be connected directly to the AG or indirectly via a V5.xAccess Node. The R-VGW and A-VGW are connected to the IMS PES via the Gm reference point. The R-MGW and A-MGW are connected to the IMS PES via the P1 reference point. PSTN/ISDN islands may also be connected via trunking media gateway function (T-MGF), controlled via the Mn reference point. Transit network functionality is supported as provided by the IMS ES 282 007 [2].
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
4.3 Constraints on services
|
The range of services that can be emulated in TISPAN NGN Release 1 is constrained by the functional architecture and the IMS SIP profile defined in ES 283 003 [4] on the Mw/Mx and ISC reference points, and of the Gm reference points in case of VGW.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
4.4 Overlap signalling
|
Overlap sending is a mechanism that is used for dialling over analogue and ISDN accesses, and is inbuilt in the inter- exchange signalling systems of the PSTN/ISDN networks. As such, it is a mechanism that the IMS-based PSTN/ISDN emulation subsystem architecture shall support, in a similar manner as for the PSTN. To support overlap signalling the PES shall support the following functionality: • at the originating side, the VGW and the AGCF shall support the ability to collect digits sent by the user to the extent of its knowledge of the dialling plan in use. As a result, the completeness of the number may be unknown, and the VGW and AGCF may, dependent on operator policy, use overlap sending; • Networks supporting overlap sending should provide a B2BUA function that has the ability to collect digits, before routeing to another network that does not support overlap sending, such that the address information is provided in a single message; • at the terminating side, e.g. when connected to a legacy PBX, the VGW and the AGCF should support based on operator policy the ability to transfer digits to the user using overlap sending; • at the terminating side, e.g. when connected to a legacy PBX, an AS may support the ability to transfer digits to the user dependent on operator policy, using overlap sending; • In case of an incoming call (from another network), the I-CSCF or TrRF or O-MGCF, possibly in combination with HSS/DNS/ENUM, will forward the call only when a sufficient number of digits have been received: - for terminating cases to access the service profile assigned to a user. Only for cases additional digits not relevant for the IMS service profile lookup are received as overlap signalling, e.g. for DDI towards a PBX, based on network options this additional overlap signalling should be sent towards the terminating user; - for transit cases when the number received points towards another network to select and forward the call to an appropriate network egress point (e.g. IBCF or I-MGCF). the solution shall interoperate with IMS networks not supporting overlap signalling without requiring any changes in those networks. NOTE 1: A terminating IMS network not supporting overlap signalling will perform a database lookup to assign a S-CSCF for an incoming call and will return a 404 error response to an INVITE with an incomplete number. • in interconnection scenarios, as a network option, it shall be possible to support overlap signalling. NOTE 2: In the PES network the service level provided to the user should not be dependent on using overlap or en-bloc sending. ETSI ETSI TS 182 012 V2.1.4 (2008-03) 11
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
5 Functional architecture
| |
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
5.1 Overview
|
The functional architecture described in the preent document is one of the possible architectural options for structuring the TISPAN PSTN/ISDN Emulation Subsystem (PES) identified in the TISPAN NGN overall architecture ES 282 001 [1]. This functional architecture uses the same architecture as the IMS defined in ES 282 007 [2] with extensions defined in the present document. Figure 3 provides an overview of the functional entities that make up this architecture and shows their relationships to the other components of the NGN architecture. Other IP Net- works IP Transport (Access and Core) T - MGF I - BGF UPSF I/S - CSCF BGCF SLF Charging Functions IWF PES Mw Mx Mr Mg Mj Mi Mp Mn Gm Gq ' ISC Cx Dx Dh Sh Ic Rf /Ro Rf /Ro Ib Iw Gq ' PSTN/ ISDN SGF MRFC MGCF MRFP Resource and Admission Control Subsystem Ie Mw IBCF Mx Mk Other types of service logic PSTN/ISDN Emulation logic Application Rf /Ro AGCF Gq ' P1 Mw P3 Ut Ut Network Attachment Subsyste e2 e2 Mx P - CSCF Mx Mx analog acc. ISDN acc. A/R- MGW A/R- VGW Figure 3: PSTN/ISDN Emulation Subsystem - Functional Architecture Most of the functional entities inside the PSTN/ISDN Emulation Subsystem are identical or derived from their IMS counterpart 282 007 [2], with the noticeable exception of an Access Gateway Control Function (AGCF) that has the responsibility of controlling residential and access media gateways. For the other functional entities, any differences are noted in the following clause. A physical entity can house functional entities supporting both PES and IMS, that can be supported by a common addressing scheme.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
5.2 Overview of Functional entities of the PES
| |
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
5.2.1 Access Gateway Control Function (AGCF)
|
This functional entity is the first point of contact for Residential Media Gateway (R-MGW) and Access Media Gateways (A-MGW). This entity is specific to the PSTN/ISDN emulation subsystem. It performs the following functions: • Act as an MGC for controlling media gateways functions (R-MGF and A-MGF) located in residential and access gateways. • Interact with the resource and admission control subsystem (RACS). • Interact with the network attachment subsystem (NASS) to retrieve line profile information. ETSI ETSI TS 182 012 V2.1.4 (2008-03) 12 • Perform signalling interworking between SIP at the Mw/Mx reference point and analog/ISDN signalling. The analog and ISDN signalling information is conveyed over the P1 reference point. • Perform signalling interworking between XCAP at the Ut reference point and legacy subscriber line (e.g. ISDN) signalling via the P1 reference point. NOTE 1: The main use-case for the interworking between XCAP and legacy subscriber line signalling is supplementary service control (registration, activation, deactivation, interrogation). • Act as a SIP User Agent with regard to IMS SIP functional entities. • Perform functions normally assigned to a P-CSCF on behalf of legacy terminals connected behind the media gateways (such as managing SIP registration procedures, generating asserted identities, and creating charging identifiers). The AGCF appears as a P-CSCF to the other CSCFs. The SIP signalling capabilities available to the AGCF are limited to those available at the Mw/Mx reference. Moreover, the AGCF shall provide basic feature logic for: • delivering the appropriate dialtone pattern; • processing mid-call events, as described in clause 12. NOTE 2: A solution based on AGCF will provide similar response time (e.g. dial tone, ring tone) as today in the PSTN networks. In case of AGCF failure, stable calls shall be preserved. Depending on implementation options, the AGCF may or may not be capable of implementing service-independent feature logic for dealing with register recall events, when it does, it can make certain decisions such as whether or not to apply dial tone on register recall, whereas in implementations where the AGCF does not implement feature logic, such decisions must be left for the AS to make. Further details on the AGCF structure and behaviour are provided in clause 12. NOTE 3: If desired, a network operator could choose to deploy an MGC that controls a set of media gateways following most of the AGCF call processing rules defined in the present document, and supports the Gm interface into an IMS or PES network via a P-CSCF, but this entity would fill the role of "Gateway (VGW)" depicted in figure 3 and would not be part of the trusted IMS core. AGCF/VGW shall support a generic solution for calls without dialling information, e.g. fixed destination call or deferred fixed destination call.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
5.2.2 Multimedia Resource Function Controller (MRFC)
|
The behaviour of the MRFC is identical in the PSTN/ISDN Emulation Subsystem and in the IMS subsystem ES 282 007 [2].
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
5.2.3 Media Gateway Control Function (MGCF)
|
The role of the MGCF is identical in the PSTN/ISDN Emulation Subsystem and in the IMS subsystem ES 282 007 [2]. Signalling procedures for interworking with ISUP signalling are slightly different due to the presence of encapsulated ISUP information inside the PES and the need to ensure full ISDN transparency in case of ISDN calls transiting through the PES.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
5.2.4 Proxy Call Session Control Function (P-CSCF)
|
The behaviour of the P-CSCF is identical in the PSTN/ISDN Emulation Subsystem and in the IMS subsystem ES 282 007 [2]. However, the P-CSCF is not used in configurations where an AGCF is required to control residential or access media gateways. In such cases, all functions normally provided by the P-CSCF will be provided directly by the AGCF. ETSI ETSI TS 182 012 V2.1.4 (2008-03) 13
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
5.2.5 Service Call Session Control Function (S-CSCF)
|
The behaviour of the S-CSCF is identical in the PSTN/ISDN Emulation Subsystem and in the IMS subsystem ES 282 007 [2].
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
5.2.6 Interrogating Call Session Control Function (I-CSCF)
|
The behaviour of the I-CSCF is identical in the PSTN/ISDN Emulation Subsystem and in the IMS subsystem ES 282 007 [2].
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
5.2.7 Breakout Gateway Control Function (BGCF)
|
The behaviour of the BGCF is identical in the PSTN/ISDN Emulation Subsystem and in the IMS subsystem ES 282 007 [2].
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
5.3 Internal Reference Points
| |
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
5.3.1 Reference Point MGCF - CSCF (Mg Reference Point)
|
The Mg reference point allows the MGCF to forward incoming session signalling (from the PSTN) to the CSCF for the purpose of interworking with PSTN networks. The protocol used for the Mg reference point is SIP. SIP messages may contain encapsulated ISUP information. The role of this reference point is identical in the PES and IMS subsystems. Details are described in TS 182 006 [3].
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
5.3.2 Reference Point CSCF - MRFC (Mr Reference Point)
|
The Mr reference point allows the S-CSCF to relay signalling messages between an application server function and an MRFC. The protocol used for the Mr reference point is SIP. The role of this reference point is identical in the PES and IMS subsystems ES 282 007 [2]. Details are described in TS 182 006 [3]. 5.3.3 Reference Point CSCF - CSCF and AGCF - CSCF (Mw Reference Point) The Mw reference point allows the communication and forwarding of signalling messaging between CSCFs and between an AGCF and a CSCF, e.g. during registration and session control. The protocol used for the Mw reference point is SIP. SIP messages exchanged over the Mw reference point may contain encapsulated ISUP information, except between the AGCF and a CSCF. The role of this reference point is identical in the PES and IMS subsystems ES 282 007 [2]. Details are described in TS 182 006 [3].
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
5.3.4 Reference Point CSCF - BGCF (Mi reference point)
|
This reference point allows the Serving CSCF to forward the session signalling to the Breakout Gateway Control Function for the purpose of interworking to the PSTN networks. The protocol used for the Mi reference point is SIP. SIP messages exchanged over the Mi reference point may contain encapsulated ISUP information. ETSI ETSI TS 182 012 V2.1.4 (2008-03) 14 The role of this reference point is identical in the PES and IMS subsystems ES 282 007 [2]. Details are described in TS 182 006 [3].
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
5.3.5 Reference Point BGCF - MGCF (Mj reference point)
|
This reference point allows the Breakout Gateway Control Function to forward the session signalling to the Media Gateway Control Function (and vice-versa) for the purpose of interworking to the PSTN networks. This reference point may also be used by an MGCF to forward session signalling to the BGCF in case of transit scenarios, if the MGCF supports transit routeing. The protocol for the Mj reference point is SIP, possibly with encapsulated ISUP information. The role of this reference point is identical in the PES and IMS subsystems ES 282 007 [2]. Details are described in TS 182 006 [3].
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
5.3.6 Reference Point BGCF - BGCF (Mk reference point)
|
This reference point allows the Breakout Gateway Control Function to forward the session signalling to another Breakout Gateway Control Function. The Mk reference point is SIP, possibly with encapsulated ISUP information. The role of this reference point is identical in the PES and IMS subsystems. Details are described in TS 182 006 [3]. 5.3.7 Reference Point AGCF, CSCF or BGCF - IBCF (Mx Reference Point) The Mx reference point allows the communication and forwarding of signalling messages between an AGCF, CSCF or a BGCF and an IBCF. NOTE: The protocol used for the Mx reference point is SIP. The role of this reference point is identical in the PES and IMS subsystems. SIP messages exchanged over the Mx reference point may contain encapsulated ISUP information, except between the AGCF and the IBCF. Details are described in TS 182 006 [3].
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
6 Service Architecture
| |
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
6.1 Overview
|
The service architecture for the PES and the IMS subsystems is the same. The generic behaviour of a application server functions is identical with respect to the PSTN/ISDN Emulation Subsystem and the TISPAN IMS. However, depending on the type of services to be emulated, certain application servers may need to understand and terminate the ISUP protocol encapsulated in SIP. Three types of Application Server Functions (ASF) can be accessed by the IMS-based PES, through the ISC or Ma reference point (see figure 4). • SIP Application Servers (SIP AS). • The IM-SSF Application Server. • The OSA SCS Application Server. ETSI ETSI TS 182 012 V2.1.4 (2008-03) 15 A SIP Application Server may contain "Service Capability Interaction Manager" (SCIM) functionality and other application servers. The SCIM functionality is an application which performs the role of interaction management. The internal structure of the application server is outside the standards. The purpose of the IM SSF is to enable access to IN service logic programs hosted in legacy SCPs. The IM-SSF functionality encompasses the emulation of the IN Call Model (BCSM) on top of SIP signalling, IN triggering and feature management mechanisms, emulation of the IN Service Switching Finite State Machine and interworking with INAP. NOTE 1: The role of the IM-SSF is identical in the PSTN/ISDN Emulation Subsystem and in the IMS subsystem ES 282 007 [2]. Basic behaviour is also identical. However, in the PES case, mapping procedures may take into account ISUP information encapsulated in SIP messages. NOTE 2: The IM SSF is intended to enable access from the PES to IN service logic programs hosted in legacy SCPs. Access to PES services (i.e. hosted in SIP-based Application Servers) from legacy SSPs in the PSTN/ISDN is outside the scope of the present document. Appropriate gateway functions (e.g. SPIRITS gateway as defined in RFC 3136 [9]) have to be implemented in the PSTN/ISDN network for supporting such scenarios. The purpose of the OSA Service Capability Server is to provide access to OSA applications, according to the OSA/Parlay framework ES 201 915-1 [8]. Further details can be found in TS 182 006 [3]. UPSF PSTN/ISDN Emulation Subsystem Transport Layer S-CSCF OSA SCS SIP-AS IN SCF OSA AS Sh Sh Si Cx ISC/Ma OSA API INAP Dx IM-SSF SLF Dh Figure 4: Value Added Services architecture The Service-CSCF to AS interface is used to forward SIP requests, based on filter criteria associated with the originating or destination user. The Interrogating-CSCF to AS interface is used to forward SIP requests destined to a Public Service Identity hosted by the AS directly to that AS. The procedures between AGCF and AS (using reference points Mw, Mx, Ic and ISC) shall be standard and open to allow for interoperability of equipment from different vendors which may be located in different operators' networks. ETSI ETSI TS 182 012 V2.1.4 (2008-03) 16
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
6.2 Reference points
| |
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
6.2.1 Reference Point S-CSCF - ASF (ISC Reference Point)
|
The role of the ISC reference point is identical with respect to the PSTN/ISDN Emulation Subsystem and the IMS subsystem. The information provided over the ISC reference point shall enable an AS to distinguish between access lines receiving PES services via a VGW and access lines receiving PES services via an AGCF both of which use the same public user identity.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
6.2.2 Reference Point UPSF - SIP AS or OSA SCS (Sh Reference Point)
|
The role of the Sh reference point with respect to the PSTN/ISDN Emulation Subsystem and the IMS subsystem is identical.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
6.2.3 Reference Point UPSF - IM SSF (Si Reference Point)
|
The role of the Si reference point with respect to the PSTN/ISDN Emulation Subsystem and the IMS subsystem is identical.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
6.2.4 Reference Point ASF- SLF (Dh Reference Point)
|
The role of the Dh reference point with respect to the PSTN/ISDN Emulation Subsystem and the IMS subsystem is identical.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
6.2.5 Reference Point ASF - UE and ASF-AGCF (Ut Reference Point)
|
The role of the Ut reference point with respect to the PSTN/ISDN Emulation Subsystem and the IMS subsystem is identical. The Ut reference point enables a A-VGW or R-VGW acting as a UE to manage information related to the services provided to the legacy equipment (e.g. ISDN terminal, ISDN PBX) it connects. The Ut reference point enables the AGCF to manage information related to the services provided to the legacy equipment (e.g. ISDN terminal, ISDN PABX) connected to the Residential or Access Media Gateways it controls. The Ut reference point applies to SIP Application Servers only. Details are described in ES 282 007 [2]. 6.2.6 Reference Point I-CSCF - AS (Ma Reference Point) The role of the Ma reference point with respect to the PSTN/ISDN Emulation Subsystem and the IMS subsystem is identical. This interface between Interrogating-CSCF and the Application Servers (i.e. SIP Application Server, OSA Service Capability Server, or CAMEL IM-SSF) is used to forward SIP requests destined to a Public Service Identity hosted by an Application Server directly to the Application Server. Details are described in TS 182 006 [3]. ETSI ETSI TS 182 012 V2.1.4 (2008-03) 17
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
7 External interfaces
| |
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
7.1 Interfaces with entities in the transfer plane
|
Transfer plane entities are defined in ES 282 001 [1].
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
7.1.1 Reference Point MGCF - T-MGF (Mn Reference Point)
|
The role of this reference point with respect to the PSTN/ISDN Emulation Subsystem and the IMS subsystem is identical.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
7.1.2 Reference Point MGCF - SGF (Ie Reference Point)
|
The Ie reference point enables the MGCF to exchange SS7 signalling information over IP with the SGF, according to the SIGTRAN architecture.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
7.1.3 Reference Point AS - SGF (P3 Reference Point)
|
The PES uses the SGF primarily in support of the MGCF signalling to the PSTN, as does the IMS subsystem. In addition, some Application Servers involved in supporting PES users may use the SGF to support non call related signalling interactions with the PSTN (e.g. TCAP-based messages for CCBS).
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
7.1.4 Reference Point MRFC - MRFP (Mp Reference Point)
|
The role of this reference point with respect to the PSTN/ISDN Emulation Subsystem and the IMS subsystem is identical.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
7.2 Interface with the UE
|
Conventional SIP UEs do not exist in PES. In PES, the User Equipment comprises one or more analogue/ISDN terminals and gateway to which they are connected, via either the Z, U, S/T or T reference point. This gateway may be an Access or Residential Media Gateway or a SIP based Access or Residential Voice over IP Gateway. When the user equipment is connected to an Access Gateway, this may be via existing V5.x Access Nodes. A Voice over IP Gateways (A-VGW and R-VGW) plays the role of a UE with regards to the P-CSCF-. VoIP gateways (A/R-VGW) interact with IMS PES via the Gm and Ut reference points. The protocol used for the Gm reference point is SIP. Details are described in ES 282 007 [2]. The role of these reference point (Gm and Ut) are identical in the PES and IMS subsystems. Media Gateways connecting legacy equipment (analog/ISDN terminals and ISDN PBXs) interact with the PES via the P1 reference point. The protocols used for the P1 reference point are H.248. When connecting ISDN terminals/PBXs to the MGW (directly or via a V5 AN), the P1 reference point also comprises back hauled DSS1. In case the access is connected via V5 Access Nodes, the analog signalling information is conveyed over the P1 reference point using back hauled V5 signalling or H.248.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
7.3 Interfaces with the user profile
|
The SLF and UPSF entities are defined in ES 282 001 [1]. The behaviour of the UPSF and SLF in relation to the PSTN/ISDN Emulation Subsystem is identical to its behaviour in relation to the IMS subsystem ES 282 007 [2]. ETSI ETSI TS 182 012 V2.1.4 (2008-03) 18
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
7.3.1 Interface with the SLF (Dx Reference Point)
|
The role of this reference point with respect to the PSTN/ISDN Emulation Subsystem and the IMS subsystem are identical.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
7.3.2 Interface with the UPSF (Cx Reference Point)
|
The role of this reference point with respect to the PSTN/ISDN Emulation Subsystem and the IMS subsystem are identical.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
7.4 Interfaces with Charging Functions
|
The following functional entities in the PES may act as charging trigger points: - AS; - BGCF; - (I-/P-/S-) CSCF; - MGCF; - MRFC; - AGCF. For off-line charging the Rf interface is used. For on-line charging the Ro interface is used. Details are described in ES 282 010 [7]. NOTE: The IBCF to which the PES is connected may also act as a charging trigger point.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
8 Interconnection with other networks
| |
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
8.1 Interfaces with the PSTN/ISDN
|
Interconnection at the signalling level is provided via the SGF. Interconnection at the media level is provided by the trunk interfaces at the T-MGF.
|
b708cbb24b9b1d04a3865f5f2ea8c6ab
|
182 012
|
8.2 Interfaces with other external IP-based Subsystems
|
Interconnection with other IP-based subsystems (including other PSTN/ISDN Emulation subsystems) is typically performed via the IBCF at the signalling level. NOTE 1: Use of the IBCF is dependant on the implementations of the interconnected operators. In case of incoming sessions from other IP networks, and in case an IBCF is used, the IBCF determines the next hop in IP routing depending on received signalling information, based on configuration data and/or data base look up. The next hop may be an I-CSCF, a BGCF or another IBCF. Interconnection between PSTN/ISDN emulation subsystems occurs either between two home domains (e.g. session originating and terminating domain) or between a visited domain and a home domain (i.e. support of roaming capabilities, see note 2). ETSI ETSI TS 182 012 V2.1.4 (2008-03) 19 NOTE 2: Roaming scenarios are inherently supported in the IMS-based PES just as the IMS architecture enables UEs in a visited network to access their home IMS via a P-CSCF in the visited IMS. When serving lines via an AGCF, due to the static characteristics of access lines connected to an AGCF, the roaming scenario supported by the IMS-based PES will typically be permanent (i.e. non-nomadic), unless rewiring of the access line to a different A-MGW is performed; typically known as wholesale scenario, this form of permanent roaming is achieved by means of an access line being physically connected to a A-MGW and an AGCF in one operator's domain and receiving its home PES services from another operator's IMS (as shown in figures 5 and 6). The above also implies that different access lines connected to the same AGCF in a visited network can receive PES services from different operators' home IMS-based PES. As in any roaming agreement, certain information will have to be exchanged off-line between the visited and home operators; for the particular scenario where the AGCF resides in a different operator's network than the rest of the IMS, this information includes the configuration of the lines being served (see clause 11.2.2) as well as an indication of the respective capabilities of the AGCF and the PES AS for them to interoperate (e.g. whether or not the AGCF supports service-independent feature logic for dealing with mid-call events). The format or the means to exchange such information is outside the scope of the present document. Based on signalling information received from the PES and local policy rules, and if an IBCF is used, the IBCF decides on a per session basis whether the RACS should be involved in the interconnection. NOTE 3: Depending on the operator policies, the decision as to whether or not media level interconnection is required (i.e. an I-BGF is inserted in the media path) for a particular session may be taken by the RACS, based on the "resource reservation service class" information that may be received from the IBCF. The RACS also choose the appropriate interconnect link for media traffic based on the information received from the IBCF, if an IBCF exists and is used. Figure 5 illustrates the case where no I-BGF is inserted. Figure 6 illustrates the case where an I-BGF is inserted by the visited network. All other interconnect scenarios identified in ES 282 007 [2] annex B are also applicable to the PES. S-CSCF AGCF IBCF IBCF Mx Mx Ic PES (visited) PES (home) To/from terminating home network Originating Visited Network Originating Home Network Access Transport Network RACS Core Transport Networks C-BGF Media Flows Figure 5: PES interconnect scenario without I-BGF ETSI ETSI TS 182 012 V2.1.4 (2008-03) 20 S-CSCF AGCF IBCF IBCF Mx Mx Ic PES (visited) PES (home) To/from terminating home network Originating Visited Network Originating Home Network Access Transport Network RACS Core Transport Networks C-BGF Media Flows I-BGF RACS Figure 6: PES interconnect scenario with I-BGF NOTE 4: As a network operator's option, an I-CSCF with encryption-based topology hiding capabilities (THIG) may also be inserted in the PES before the IBCF. This is not represented on figures 5 and 6. 9 Interfaces with the Network Attachment Subsystem (NASS) The e2 reference point supports information transfer between the P-CSCF or the AGCF and the Network Attachment Subsystem. The role of this reference point with respect to the PSTN/ISDN Emulation Subsystem and the IMS subsystem is identical. NOTE: Interaction with the NASS is not be required in case the AGCF controls access gateways only. 10 Interface with the Resource and Admission Control Subsystem (RACS) The Gq' reference point enables the P-CSCF or the AGCF to interact with the resource control subsystem for the following purposes: - authorization of QoS resources; - resource reservation; - gate control (including NAPT binding information relay). With regard to the RACS architecture; the P-CSCF and the AGCF play the role of an Application Function (AF). The role of this reference point with respect to the PSTN/ISDN Emulation Subsystem and the IMS subsystem is identical. NOTE: Interaction with the NASS may not be required in case the AGCF controls access gateways only and dedicated transport resources are used to support PES traffic. ETSI ETSI TS 182 012 V2.1.4 (2008-03) 21 In case of network interconnection, interactions with the resource control subsystem may also take place at the edge of the PES, at the IBCF level for the following purposes: - gate control (including NAPT binding information relay). With regard to the RACS architecture; the IBCF plays the role of an Application Function (AF). Details are described in TS 183 021 [6].
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.