WO2009089953A1 - Method and system for transcoding avoidance in border gateways - Google Patents

Method and system for transcoding avoidance in border gateways Download PDF

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Publication number
WO2009089953A1
WO2009089953A1 PCT/EP2008/066064 EP2008066064W WO2009089953A1 WO 2009089953 A1 WO2009089953 A1 WO 2009089953A1 EP 2008066064 W EP2008066064 W EP 2008066064W WO 2009089953 A1 WO2009089953 A1 WO 2009089953A1
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Prior art keywords
call
functional entity
policy decision
codec
transcoding
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French (fr)
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Peter Goldstein
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Nokia Solutions and Networks Oy
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Nokia Siemens Networks Oy
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M7/00—Arrangements for interconnection between switching centres
    • H04M7/006—Networks other than PSTN/ISDN providing telephone service, e.g. Voice over Internet Protocol (VoIP), including next generation networks with a packet-switched transport layer
    • H04M7/0072—Speech codec negotiation
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
    • H04L65/10—Architectures or entities
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L69/00—Network arrangements, protocols or services independent of the application payload and not provided for in the other groups of this subclass
    • H04L69/24—Negotiation of communication capabilities
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
    • H04L65/10—Architectures or entities
    • H04L65/1016—IP multimedia subsystem [IMS]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
    • H04L65/10—Architectures or entities
    • H04L65/102—Gateways
    • H04L65/1023—Media gateways
    • H04L65/103—Media gateways in the network
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
    • H04L65/10—Architectures or entities
    • H04L65/102—Gateways
    • H04L65/1043—Gateway controllers, e.g. media gateway control protocol [MGCP] controllers

Definitions

  • This invention relates to a method and system for transcoding avoidance in Border Gateways according to the preamble of claim 1 respectively claim 6.
  • the architecture framework for Next Generation Network NGN describes beside others the functional entities of the gateway connecting different networks.
  • the different networks could be either core networks of different network providers or access networks connected to a core network.
  • the Service Stratum contains besides others the functional entity Call/Session Control, whereas the Transport Stratum contains in the Resource and Admission Control Area the Policy Decision Functional Entity PD-FE and in the Transport Area the Policy Enforcing Functional Entity PE-FE.
  • Network operators do assign a specific codec to be used in the interconnecting network (between networks of different network operators) based on bilateral agreement or specify a specific codec to be used in their core network independent of the codec used in the access network, based on criteria such as bandwidth; see EP 1 758 333 Al and WO 2007/022818 Al [1] or to connect IP end devices using different codecs.
  • the network element connecting the different networks is hereafter called border gateway BGW.
  • WO 2004/006597 Al / EP 1 586 209 Bl [2] discloses the «Avoidance of transcoding or interruption on live load coding exchange in extant connections)).
  • This disclosure does not solve the above mentioned problem, since it is restricted to a media gateway MG between a TDM- and a packet-based network and is related to a media change during an extant connection, e.g. voice to fax and vice versa.
  • An example would be where person A assures by voice communication with a person B, that the person B will be able to receive a confidential fax and only then sends the fax. This can be done by using a normal telephone apparatus combined with a Fax-Device Gr .3.
  • Figure 5 BGW containing Policy Enforcing Functional Entity and Policy Decision Functional Entity
  • Figure 6 BGW containing Policy Enforcing Functional Entity and an interface to Policy Decision Functional Entity.
  • Fig. 2 shows the end-to-end negotiation between two subscribers A and B, where an A-subscriber initiates a call to a B-subscriber and the call is identified by a call/connection identifier «Call-Id».
  • Each IP end device of the subscribers A, B is connected to an access router R of an access network, where the media stream is routed to a border gateway BGW.
  • the signalling SIP, SDP is routed via an access router R to the Physical Entity «Call/Session Control Function» PE-CSCF, the latter is called for the sake of simplicity just «Call/Session Controller» PE- CSCF.
  • the protocol used between the Call/Session Controller PE-CSCF and the Physical Entity containing a Policy Decision Functional Entity PD-FE, which may or may not be an integra- ted part of the Border Gateway BGW is enhanced by a new information element 12. Further details see Fig. 3.
  • the information element 12 contains a field «common codec» of type «true/false» or «Y/N» or «yes/no", this field is accompanied by another field «Call-Id» identifying the call by a call/connection identifier, see e.g. SIP.
  • the logic of the Policy Decision Functional Entity PD-FE is enhanced by a table containing the information «common codec» for each active call identified by the «Call-Id».
  • the «Call-Id» is used to generate the appropriate address to access (read/write) the said table.
  • a procedure is provided to analyze for each RTP stream, if transcoding is to be applied or not by determining the media type and in case of voice accessing the correspon- ding element of the said table to get the «common codec» information and set the appropriate flag for the further processing in the Policy Decision Functional Entity PD-FE.
  • Protocol 10 (based on Diameter as specified in Q.3301.1 or H.248/SDP which is also a possible candidate) is used to transmit these information elements «Call-Id» and «common codec» from the Call/Session Control Function PE-CSCF to the Border Gateway BGW.
  • the enhancements to the protocol 10 are shown exemplary by using H.248/SDP in table 1.
  • Table 1 Messages and Message format with additional fields.
  • the protocol 11 used between the Policy Decision Functional Entity PD-FE contained in a separate Physical Entity and the Policy Enforcing Functional Entity PE-FE in the Border Gateway BGW is preferably according to an open standard, see Fig. 5 and 6.
  • An example for such a protocol is H.248 (accompanied by SDP) or COPS.
  • the Policy Decision Functional Entity PD-FE maintains a table to store the new information element «common codec» on a per call basis. If the information «common codec» is true ( «Y», «yes») , then the Policy Decision Function Entity PD-FE ignores the existing rule stored in the Policy Decision Functional Entity PD-FE for applying the assigned codec (for crossing network borders) for this voice call and instructs the Policy Enforcing Functional Entity PE-FE accordingly. That means for the media «voice» no codec information will be sent to the Policy Enforcing Functional Entity when requesting the creation of the appropriate context.
  • Fig. 4 shows the new procedure introduced in the Policy Decision Functional Entity PD-FE:
  • the media type is determined and in case of voice, the corresponding element in said table is accessed to get the «common codec» information and the flags for the further processing are set, i.e. preparing the instruction to be sent to the Policy Enforcing Functional Entity PE-FE.
  • the Border Gateways BGW includes either only the Policy Enforcing Functional Entity PE-FE and thus provides the voice related signal processing resources or in addition to the Policy Enforcing Functional Entity PE-FE also the Policy Decision Functional Entity PD-FE.
  • Session Border Controllers of pre-NGN networks handling media and signalling can be considered as a physical implementation of a NGN Border Gateway containing the Policy Decision Functional Entity PD-FE and the Policy Enforcing Functional Entity PE-FE combined with a Signalling Gateway.
  • the Policy Enforcing Functional Entity PE-FE of the Border Gateway BGW providing the signal processing functions for voice, e.g. one or more codecs, is informed either by the integrated or external Policy Decision Functional Entity PD- FE based on the information received from the Call/Session Controller PE-CSCF, where the call set up handling takes place, if a common codec has been negotiated or not.
  • the codec could be negotiated between the Policy Decision Functional Entities PD-FE involved in the call.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Computer Security & Cryptography (AREA)
  • Multimedia (AREA)
  • Data Exchanges In Wide-Area Networks (AREA)
  • Telephonic Communication Services (AREA)

Abstract

The architecture framework for Next Generation Network NGN, as defined by ITU-T and ETSI, includes border gateways (BGW) to connect different networks of different network providers or to connect access networks to the core network. Based on bilateral agreement a specific codec is used in the interconnecting network or a specific codec may be used in the core network independent of the codec used in the access network, respectively. If the two IP end devices do have a common codec, the problem of unwanted transcoding arises, which leads to additional delay and reduces the audio quality caused by converting one coding scheme into another coding scheme. In order to avoid unnecessary transcoding, an information element (12) is introduced which contains the result of an end-to-end negotiation on common codecs.

Description

Method and system for transcoding avoidance in Border Gateways
This invention relates to a method and system for transcoding avoidance in Border Gateways according to the preamble of claim 1 respectively claim 6.
The architecture framework for Next Generation Network NGN, as defined by ITU-T and ETSI, describes beside others the functional entities of the gateway connecting different networks. The different networks could be either core networks of different network providers or access networks connected to a core network. The Service Stratum contains besides others the functional entity Call/Session Control, whereas the Transport Stratum contains in the Resource and Admission Control Area the Policy Decision Functional Entity PD-FE and in the Transport Area the Policy Enforcing Functional Entity PE-FE. Network operators do assign a specific codec to be used in the interconnecting network (between networks of different network operators) based on bilateral agreement or specify a specific codec to be used in their core network independent of the codec used in the access network, based on criteria such as bandwidth; see EP 1 758 333 Al and WO 2007/022818 Al [1] or to connect IP end devices using different codecs. The network element connecting the different networks is hereafter called border gateway BGW.
A number of different (bit rate) codecs are defined for the transport of voice over IP. However it is not economical feasible to provide all these codecs in IP based devices. That is why network operators provide in their networks network elements with the "transcoding" capability. This makes it possible to "connect" IP end devices with different codecs .
The above mentioned method suffers from the drawback that unnecessary transcoding may be present. Transcoding intro- duces additional delay and reduces the audio quality caused by converting one coding scheme into another coding scheme.
On the other hand an end to end based codec negotiation has been defined (ITU-T, IETF) to agree, if possible, to a codec available in both end devices, considering that transcoding reduces the voice quality by adding delay and decreasing the audio quality.
Nevertheless this negotiation does not avoid transcoding per se, because the Border Gateways, where the transcoding takes place are not involved in the codec negotiation, see Fig. 1 BGW.
It is therefore a task of the present invention, to provide a method and a system for avoiding unwanted transcoding causing a reduced voice service quality.
WO 2004/006597 Al / EP 1 586 209 Bl [2] discloses the «Avoidance of transcoding or interruption on live load coding exchange in extant connections)). This disclosure does not solve the above mentioned problem, since it is restricted to a media gateway MG between a TDM- and a packet-based network and is related to a media change during an extant connection, e.g. voice to fax and vice versa. An example would be where person A assures by voice communication with a person B, that the person B will be able to receive a confidential fax and only then sends the fax. This can be done by using a normal telephone apparatus combined with a Fax-Device Gr .3.
The object to provide a method and a system for avoiding unwanted transcoding causing a reduced voice service quality is solved by the method steps specified in claim 1 and by a system given with the features in claim 6. By the introduction of i) an information element containing at least a field
«call/connection identifier» Call-Id and a field «common codec» of type «true/false» (Y/N) in the information exchange between a Physical Entity Call/Session Con¬ troller PE-CSCF and a Physical Entity containing the Policy Decision Functional Entity PD-FE and by a table in the Policy Decision Functional Entity PD-FE, where the table elements store the information «common codec» on a per call basis and a procedure for the Policy Decision Functional Entity PD-FE whereby ii) in the involved border gateway BGW in case of «common codec» = true the transcoding is avoided or in case of «common codec» = false an predefined transcoding is performed according to the rule based on origin and destination , and contained in the the Policy Decision Functional Entity; an unwanted transcoding between the two peers A and B can be avoided. This information element («common codec») does not affect other protocols and can easily be implemented in existing systems.
Further advantageous embodiments of the present invention are given in dependent claims.
The invention will be now described in preferred embodiments with reference to the accompanying figures wherein:
Figure 1 Transcoding in the Border Gateways of network A and network B according to the state of the art; Figure 2 Transcoding avoidance in the Border Gateways of network A and network B according to a preferred embodiment of the invention;
Figure 3 Protocol elements and table for «common codec»; Figure 4 Media (voice) /RTP - Codec Analysis in the Policy Decision Functional Entity;
Figure 5 BGW containing Policy Enforcing Functional Entity and Policy Decision Functional Entity; Figure 6 BGW containing Policy Enforcing Functional Entity and an interface to Policy Decision Functional Entity.
Fig. 2 shows the end-to-end negotiation between two subscribers A and B, where an A-subscriber initiates a call to a B-subscriber and the call is identified by a call/connection identifier «Call-Id».
Each IP end device of the subscribers A, B is connected to an access router R of an access network, where the media stream is routed to a border gateway BGW. The signalling SIP, SDP is routed via an access router R to the Physical Entity «Call/Session Control Function» PE-CSCF, the latter is called for the sake of simplicity just «Call/Session Controller» PE- CSCF. The protocol used between the Call/Session Controller PE-CSCF and the Physical Entity containing a Policy Decision Functional Entity PD-FE, which may or may not be an integra- ted part of the Border Gateway BGW is enhanced by a new information element 12. Further details see Fig. 3. The information element 12 contains a field «common codec» of type«true/false» or «Y/N» or «yes/no», this field is accompanied by another field «Call-Id» identifying the call by a call/connection identifier, see e.g. SIP.
With reference to Fig. 3 the logic of the Policy Decision Functional Entity PD-FE is enhanced by a table containing the information «common codec» for each active call identified by the «Call-Id». The «Call-Id» is used to generate the appropriate address to access (read/write) the said table. Furthermore a procedure is provided to analyze for each RTP stream, if transcoding is to be applied or not by determining the media type and in case of voice accessing the correspon- ding element of the said table to get the «common codec» information and set the appropriate flag for the further processing in the Policy Decision Functional Entity PD-FE. Protocol 10 (based on Diameter as specified in Q.3301.1 or H.248/SDP which is also a possible candidate) is used to transmit these information elements «Call-Id» and «common codec» from the Call/Session Control Function PE-CSCF to the Border Gateway BGW. The enhancements to the protocol 10 are shown exemplary by using H.248/SDP in table 1.
Messages_ ADD, MODIFY
Message format: MEGACO/x.y. Transaction = . Context = ... Call-Id = ... new info element ADD (MODIFY) H.24!
Figure imgf000006_0001
Figure imgf000006_0002
Table 1: Messages and Message format with additional fields.
If the Policy Decision Functional Entity PD-FE is not integrated in the Border Gateway BGW, then the protocol 11 used between the Policy Decision Functional Entity PD-FE contained in a separate Physical Entity and the Policy Enforcing Functional Entity PE-FE in the Border Gateway BGW is preferably according to an open standard, see Fig. 5 and 6. An example for such a protocol is H.248 (accompanied by SDP) or COPS.
The Policy Decision Functional Entity PD-FE maintains a table to store the new information element «common codec» on a per call basis. If the information «common codec» is true («Y», «yes») , then the Policy Decision Function Entity PD-FE ignores the existing rule stored in the Policy Decision Functional Entity PD-FE for applying the assigned codec (for crossing network borders) for this voice call and instructs the Policy Enforcing Functional Entity PE-FE accordingly. That means for the media «voice» no codec information will be sent to the Policy Enforcing Functional Entity when requesting the creation of the appropriate context.
Fig. 4 shows the new procedure introduced in the Policy Decision Functional Entity PD-FE:
For each RTP stream the media type is determined and in case of voice, the corresponding element in said table is accessed to get the «common codec» information and the flags for the further processing are set, i.e. preparing the instruction to be sent to the Policy Enforcing Functional Entity PE-FE.
The Border Gateways BGW includes either only the Policy Enforcing Functional Entity PE-FE and thus provides the voice related signal processing resources or in addition to the Policy Enforcing Functional Entity PE-FE also the Policy Decision Functional Entity PD-FE.
Session Border Controllers of pre-NGN networks handling media and signalling can be considered as a physical implementation of a NGN Border Gateway containing the Policy Decision Functional Entity PD-FE and the Policy Enforcing Functional Entity PE-FE combined with a Signalling Gateway.
The Policy Enforcing Functional Entity PE-FE of the Border Gateway BGW providing the signal processing functions for voice, e.g. one or more codecs, is informed either by the integrated or external Policy Decision Functional Entity PD- FE based on the information received from the Call/Session Controller PE-CSCF, where the call set up handling takes place, if a common codec has been negotiated or not.
In another embodiment of this invention the codec could be negotiated between the Policy Decision Functional Entities PD-FE involved in the call.
List of reference numerals
10 Resource control protocol, Rs interface; ITU-T Rec. Q.3301.1 or alternatively H.248/SDP (another possible candidate for the resource control protocol at the Rs interface)
11 protocols H.248/SDP, COPS
12 Common codec Information Element
List of used symbols
BGW Border Gateway
Call-Id Call (Connection) Identifier
Co-Codec Common Codec
COPS Common Open Policy Service, Protocol; IETF RFC 274! CSCF Call/Session Control Function
ETSI European Technical Standardization Institute
IETF Internet Engineering Task Force
ITU-T International Telecommunication Union
PD-FE Policy Decision Functional Entity PE-FE Policy Enforcing Functional Entity
PE-CSCF Physical Entity «Call/Session Control Function»
R Router RFC Request For Comment
RTP Real Time Transport Protocol, IETF RFC 1889
SBC Session Border Controller
SDP Session Description Protocol, IETF RFC 2327 SIP Session Initiation Protocol, IETF RFC 2543
H.248 MEGACO (Media Gateway Control Protocol/Resource Control Protocol), ITU-T/IETF
References [1] WO 2007/022818 Al
«Method for the manipulation of speech packets in an IP-Gatway»
Siemens Schweiz AG; CH - 8047 Zurich.
[2] WO 2004/006597 Al / EP 1 586 209 Bl «Avoidance of transcoding or interruption on live load coding exchange in extant connections)) Siemens Aktiengesellschaft, DE - 80333 Munich

Claims

Claims
1. Method for avoiding transcoding in a Border Gateway (BGW) of an IP network evaluating the result of a Codec negotiation between two IP end devices (A, B) , where - to the IP end devices an A- and a B-subscriber are associated; - each IP end device of the subscribers (A, B) is connected to an access router (R) of an access network, the A-subscriber initiates a call to the B-subscriber and the call is identified by a call/connection identifier (Call-Id) , the method comprising the steps: i) an information element (12) containing at least a field
«call/connection identifier» (Call-Id) and a field «common codec» is introduced in the information exchange between a Physical Entity Call/Session Controller (PE- CSCF) and a Policy Decision Functional Entity (PD-FE) ; ii) the Policy Decision Functional Entity (PD-FE) maintains a table, where each element of the table stores the information «common codec» as received by the
Call/Session Controller; iii) in the involved Policy Decision Functional Entity (PD- FE) a procedure is introduced, wherein in case of «common codec» = true a flag with the meaning «transcoding avoidance» is set or in case of «common codec» = false a flag with the meaning «process rule» is set; iv) the Policy Decision Functional Entity informs (PD-FE) the
Policy Enforcing Functional Entity (PE-FE) to - create a context for an RTP-stream with transcoding according the indicated codec from the «process rule» or to
- create a context for an RTP-stream without transcoding.
2. Method according to claim 1 ; characterised in that in step iii) the involved Policy Decision Functional Entity (PD-FE) is integrated in the border Gateway (BGW) .
3. Method according to claim 1 ; characterised in that in step iii) the involved Policy Decision Functional Entity (PD-FE) is external to the border Gateway (BGW) .
4. Method according to one of the claims 1 to 3; characterised in that the Codec negotiation is performed by the Policy Decision Functional Entities (PD-FE) in the involved networks.
5. Method according to one of the claims 1 to 4 ; characterised in that in step i) the information exchange between a Physical Entity Call/Session Controller (PE-CSCF) and a Policy Decision Functional Entity (PD-FE) is based on the protocols H.248 accompanied by SDP.
6. System for avoiding transcoding in a Border Gateway
(BGW) of an IP network evaluating the result of a Codec negotiation between two IP end devices (A, B) , where to the IP end devices an A- and a B-subscriber are associated; each IP end device of the subscribers (A, B) is connected to an access router (R) of an access network, the A-subscriber initiates a call to the B-subscriber and the call is identified by a call/connection identifier (Call-Id) , characerised in that i) an information element (12) containing at least a field «call/connection identifier» (Call-Id) and a field «common codec» is contained in the information exchange between a Physical Entity Call/Session Controller (PE- CSCF) and a Policy Decision Functional Entity (PD-FE) ; ii) the Policy Decision Functional Entity (PD-FE) maintains a table, where each element of the table stores the information «common codec» as received by the Call/Session Controller; iii) in the involved Policy Decision Functional Entity (PD- FE) a procedure is introduced, wherein in case of «common codec» = true a flag "transcoding avoidance" is set or in case of «common codec» = false a flag "process rule" is set; iv) the Policy Decision Functional Entity informs (PD-FE) the Policy Enforcing Functional Entity (PE-FE) to
- create a context for an RTP-stream with transcoding according the indicated codec from the rule or to
- create a context for an RTP-stream without transcoding.
Border Gateway including Policy Decision Functional Entity and Policy Enforcing Functional Entity.
7. System according to claim 6; characterised in that in step iii) the involved Policy Decision Functional Entity (PD-FE) is integrated in the border Gateway (BGW) .
8. System according to claim 6; characterised in that in step iii) the involved Policy Decision Functional Entity (PD-FE) is external to the border Gateway (BGW) .
9. System according to one of the claims 6 to 8 ; characterised in that the Codec negotiation is performed by the Policy Decision
Functional Entities (PD-FE) in the involved networks.
10. System according to one of the claims 6 to 9; characterised in that in step i) the information exchange between a Physical Entity
Call/Session Controller (PE-CSCF) and a Policy Decision Functional Entity (PD-FE) is based on the protocols H.248 accompanied by SDP.
PCT/EP2008/066064 2008-01-16 2008-11-24 Method and system for transcoding avoidance in border gateways Ceased WO2009089953A1 (en)

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US10148703B2 (en) 2014-10-09 2018-12-04 T-Mobile Usa, Inc. Service capabilities in heterogeneous network
US11799922B2 (en) 2016-12-21 2023-10-24 T-Mobile Usa, Inc. Network core facilitating terminal interoperation
US10771509B2 (en) 2017-03-31 2020-09-08 T-Mobile Usa, Inc. Terminal interoperation using called-terminal functional characteristics

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1758333A1 (en) * 2005-08-24 2007-02-28 Siemens Schweiz AG Method for manipulation of voice packets in an IP gateway

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE80333C (en)
DE10231027B3 (en) 2002-07-09 2004-03-18 Siemens Ag Avoidance of transcoding or termination when changing payload coding in existing connections

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1758333A1 (en) * 2005-08-24 2007-02-28 Siemens Schweiz AG Method for manipulation of voice packets in an IP gateway

Non-Patent Citations (4)

* Cited by examiner, † Cited by third party
Title
"Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); Resource and Admission Control: H.248 Profile for controlling Border Gateway Functions (BGF) in the Resource and Admission Control Subsystem (RACS); Protocol specification; ETSI ES 283 018", ETSI STANDARDS, LIS, SOPHIA ANTIPOLIS CEDEX, FRANCE, vol. TISPAN, no. V2.3.0, 1 November 2007 (2007-11-01), XP014040864, ISSN: 0000-0001 *
ANDERSON T W ET AL: "THE EMERGING RESOURCE AND ADMISSION CONTROL FUNCTION STANDARDS AND THEIR APPLICATION TO THE NEW TRIPLE-PLAY SERVICES", BELL LABS TECHNICAL JOURNAL, WILEY, CA, US, vol. 12, no. 1, 21 March 2007 (2007-03-21), pages 5 - 21, XP001541382, ISSN: 1089-7089 *
CHU K: "Latest Draft of G.IP2IP (ver 1.7)", TELECOMMUNICATIONS INDUSTRY ASSOCIATION TR-30.1 MEETING, 21 August 2007 (2007-08-21) - 22 August 2007 (2007-08-22), Arlington, VA, US, pages 1 - 19, XP002487600 *
INTERNATIONAL TELECOMMUNICATION UNION: "Resource control protocol no. 1 (rcp1) Protocol at the interface between service control entities and the Policy Decision Physical Entity (PD-PE) (Rs interface)", SERIES Q: SWITCHING AND SIGNALLING SIGNALLING REQUIREMENTS AND PROTOCOLS FOR THE NGN - RESOURCE CONTROL PROTOCOLS Q.3301.1, March 2007 (2007-03-01), GENEVA, CH, pages 1 - 54, XP002487599 *

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