1、 International Telecommunication Union ITU-T J.460.2TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (06/2008) SERIES J: CABLE NETWORKS AND TRANSMISSION OF TELEVISION, SOUND PROGRAMME AND OTHER MULTIMEDIA SIGNALS IPCablecom2 residential SIP telephony: embedded digital voice adapter (E-DVA) specificat
2、ion Recommendation ITU-T J.460.2 Rec. ITU-T J.460.2 (06/2008) i Recommendation ITU-T J.460.2 IPCablecom2 residential SIP telephony: embedded digital voice adapter (E-DVA) specification Summary Recommendation ITU-T J.460.2 defines the embedded Digital Voice Adaptor (E-DVA) requirements for the analog
3、 interface and for powering of the E-DVA. An embedded DVA is a DOCSIS cable modem (CM) integrated with an IPCablecom2 DVA. These requirements enable a sufficiently reliable service to meet assumed consumer expectations related to residential telephony. Source Recommendation ITU-T J.460.2 was approve
4、d on 13 June 2008 by ITU-T Study Group 9 (2005-2008) under Recommendation ITU-T A.8 procedure. ii Rec. ITU-T J.460.2 (06/2008) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication technolog
5、ies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommun
6、ication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas o
7、f information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operati
8、ng agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure e.g. interoperability or applicability) and compliance with the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or
9、 some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice
10、 or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation developmen
11、t process. As of the date of approval of this Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementers are cautioned that this may not represent the latest information and are therefore s
12、trongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2009 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T J.460.2 (06/2008) iii CONTENTS Page 1 Scope 1 2 References.
13、1 2.1 Normative References 1 2.2 Informative References 2 2.3 Reference Acquisition 2 3 Terms and Definitions 2 4 Abbreviations, acronyms and conventions. 3 4.1 Abbreviations and Acronyms . 3 4.2 Conventions 4 5 Overview 4 5.1 IPCablecom2 Overview 4 5.2 Service Goals 4 5.3 IPCablecom2 Reference Arch
14、itecture 5 5.4 Embedded Digital Voice Adaptor 5 6 E-DVA power requirements. 5 6.1 Power Considerations. 6 6.2 Typical E-DVA Traffic Model. 6 6.3 Service Requirements Under AC Fail Conditions 6 6.4 Local Powering with Battery Backup. 6 7 E-DVA analog port requirements. 6 8 Client requirement 6 8.1 Pr
15、ovisioning 6 8.2 Security. 7 8.3 NAT/Firewall Traversal . 7 8.4 Codecs 7 8.5 Loopback Test Capability. 8 9 E-DVA Monitoring requirements. 9 9.1 eCM Monitoring. 10 9.2 E-DVA Monitoring 10 9.3 Battery-Backup Monitoring 10 Appendix I Example of a power calculation. 12 I.1 Loop Start Signaling. 14 I.2 G
16、eneral Supervision . 15 I.3 General Ringing 17 I.4 Voice Grade Analog Transmission 18 1.5 Out of Service Requirements 22 1.6 Message Waiting Indicator. 24 Rec. ITU-T J.460.2 (06/2008) 1 Recommendation ITU-T J.460.2 IPCablecom2 residential SIP telephony: embedded digital voice adapter (E-DVA) specifi
17、cation 1 Scope This Recommendation defines the embedded Digital Voice Adaptor (E-DVA) requirements for the analog interface and for powering of the E-DVA. An embedded DVA is a DOCSIS cable modem (CM) integrated with an IPCablecom2 DVA. The purpose of this Recommendation is to define a set of require
18、ments that will enable a sufficiently reliable service to meet assumed consumer expectations related to residential telephony. These assumed expectations include constant availability, including availability during power failure at the customers premises, and access to emergency services (e.g., 121
19、or 911). It is an important objective of this work that interoperability between IPCablecom 2.0 and 3GPP IMS is provided. IPCablecom 2.0 is based upon 3GPP IMS, but includes additional functionality necessary to meet the requirements of cable operators. Recognizing developing converged solutions for
20、 wireless, wireline, and cable, it is expected that further development of IPCablecom 2.0 will continue to monitor and contribute to IMS developments in 3GPP, with the aim of alignment of 3GPP IMS and IPCablecom 2.0. NOTE The structure and content of this Recommendation have been organized for ease
21、of use by those familiar with the original source material; as such, the usual style of ITU-T recommendations has not been applied. 2 References 2.1 Normative References The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute prov
22、isions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendati
23、ons and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. CODEC-MEDIA Recommendation ITU-T J.361 (2006), IPCabl
24、ecom2 Codec Media. DOCSIS OSSIv2.0 ANSI/SCTE 79-2 2002, DOCS 2.0 Operations Support System Interface. DOCSIS RFIv2.0 Recommendation ITU-T J.122 (2002), Second-generation transmission systems for interactive cable television services IP cable modems. eDOCSIS Recommendation ITU-T J.126 (2007), Embedde
25、d Cable Modem device specification. G.168 Recommendation ITU-T G.168 (2004), Digital network echo cancellers. G.711 Recommendation ITU-T G.711 (1988), Pulse code modulation (PCM) of voice frequencies. PKT 23.228 Recommendation ITU-T J.366.3 (Draft), IPCablecom2 IP Multimedia Subsystem Stage 2 (3GGP
26、TS 23.228). PKT 24.229 Recommendation ITU-T J.366.4 (Draft), IPCablecom2 SIP and SDP Stage 3 (3GPP TS 24.229). 2 Rec. ITU-T J.460.2 (06/2008) PKT 33.203 Recommendation ITU-T J.366.7 (Draft), IPCablecom2 Access Security for IP-Based Services (3GPP TS 33.203). RFC 4330 IETF RFC 4330, Simple Network Ti
27、me Protocol version 4 for IPv6, IPv4, and OSI, January, 2006. RSTF Recommendation ITU-T J.460.1, IPCablecom2 Residential SIP Telephony Feature Specification. SEC1.5 Recommendation ITU-T J.170, IPCablecom security specification. RST E-UE Prov Recommendation ITU-T J.460.4 (draft) IPCablecom2 RST E-UE
28、Provisioning Specification. 2.2 Informative References This Recommendation uses the following informative references. ARCH-FRM TR Recommendation ITU-T J.360, IPCablecom2 Architecture Framework. ID MMUSIC LOOPBACK IETF Internet Draft, An Extension to the Session Description Protocol (SDP) for Media L
29、oopback, draft-ietf-mmusic-media-loopback-04.txt, August 2006, work in progress. ID SIP ANSWERMODE IETF Internet Draft, Requesting Answering Modes for the Session Initiation Protocol (SIP), draft-ietf-sip-answermode-01, April 2006, work in progress. Key Smith P. Key and D. Smith (editors). 1999. The
30、 Internet another vendor may omit the same item. 5 Overview 5.1 IPCablecom2 Overview The IPCablecom2 project is aimed at defining interface Recommendations that can be used to develop interoperable equipment capable of providing packet-based voice, video, and other high-speed multimedia services ove
31、r hybrid fibre coax (HFC) cable systems utilizing the Data-Over-Cable Interface Specification DOCSIS RFIv2.0. 5.2 Service Goals One application of the IPCablecom2 architecture is packet-based voice communications for cable system subscribers. The IPCablecom2 architecture as a whole enables voice com
32、munications, video, and data services based on bidirectional transfer of Internet Protocol (IP) traffic between the cable system headend and customer locations, over an all-coaxial or HFC cable network as shown in simplified form in Figure 1. Figure 1 Telephony Services Over the Data-Over-Cable Syst
33、em Rec. ITU-T J.460.2 (06/2008) 5 The transmission path over the cable system is realized by a cable modem termination system (CMTS) and at each customer location by a cable modem (CM). The E-DVA includes an embedded cable modem and a Residential SIP Telephony (RST) client and analog ports for telep
34、hone devices. The E-DVA may include digital ports. The conversion between digital RST signaling and voice to analog telephone interfaces is accomplished within the E-DVA. 5.3 IPCablecom2 Reference Architecture For a description of the IPCablecom2 architecture and Functional Components, please refer
35、to ARCH-FRM TR. 5.4 Embedded Digital Voice Adaptor A Digital Voice Adaptor (DVA) is an IPCablecom2 client device that contains a subscriber-side interface to the subscribers CPE (e.g., telephone) and a network-side signaling interface to call control elements in the network (e.g., P-CSCF, S-CSCF, Ap
36、plication servers, etc.). A DVA provides codecs and all signaling and encapsulation functions required for media transport and call signaling. DVAs reside at the customer side and are connected to other IPCablecom2 network elements via the HFC access network (DOCSIS). IPCablecom2 DVAs are required t
37、o support the SIP protocol as specified in IPCablecom2 Recommendation RSTF. IPCablecom2 only defines support for an embedded DVA (E-DVA). An E-DVA is a single hardware device that incorporates a DOCSIS 1.1 or higher CM as well as an IPCablecom2 DVA component. Figure 2 shows a representative function
38、al diagram of an E-DVA. Additional E-DVA functionality is further defined in ARCH-FRM TR. For the purposes of this Recommendation, DVA is interpreted to be identical to E-DVA. Figure 2 E-DVA Protocols 6 E-DVA power requirements This clause defines the power requirements of the E-DVA. This includes p
39、ower consumption and presents associated traffic models recommended for power consumption calculations. 6 Rec. ITU-T J.460.2 (06/2008) 6.1 Power Considerations Local power refers to utilizing the subscribers home AC utility power as the supply for the E-DVA. A battery backup is utilized to provide t
40、elephony services when the utility power fails. 6.2 Typical E-DVA Traffic Model In order to properly dimension the power equipment, it is necessary to calculate long-term average power usage. Since these are likely to vary considerably from location to location, it is impossible to have a single ans
41、wer. One method to estimate the average long-term power requirements is described in Appendix I. 6.3 Service Requirements Under AC Fail Conditions The E-DVA MUST remain operational during the switch between AC outage to battery backup. The E-DVA MUST also maintain provisioned services (operational m
42、eans capable of originating calls, ringing, and terminating calls, if provisioned as in-service). When in battery mode, services will be offered as configured by the operator. This configuration may be different from the services when provided with AC power. The E-DVA MUST maintain established telep
43、hony calls across the switchover between AC power and battery backup. Since data traffic is not required for an IPCablecom2 service, the E-DVA data service MAY be de-activated immediately under local AC power fail conditions. 6.4 Local Powering with Battery Backup Local powering is accomplished util
44、izing a UPS that converts household AC power to DC power for the E-DVA. The UPS also provides battery backup to bridge E-DVA operation through typical local power outages. In addition, telemetry signals provide remote monitoring capability for local AC power and battery conditions. The indoor climat
45、e controlled environment is typically desired for battery placement to maximize battery life. E-DVAs MAY include an embedded UPS or utilize an external UPS. 7 E-DVA analog port requirements The E-DVA analog port represents an interface between the IPCablecom2/DOCSIS/IP (Internet protocol) network an
46、d devices designed to function when connected to the PSTN using standard PSTN interfaces. The subscriber side of this interface is an analog interface consistent with the PSTN, and the network side of this interface is a digital interface to the IP-based IPCablecom2 network, which rides on top of th
47、e DOCSIS transport. It is expected that many operators will choose to use the IPCablecom2 architecture to offer services to customers in residential dwellings. In such applications, the E-DVA will reside at the subscriber premises, typically as an interior unit with battery backup. Finally, because
48、the network side of the port interface is digital, and the device resides close to the subscriber, the analog subscriber side of the port interface will only be required to support relatively short metallic (copper twisted pair) drops (i.e., 150 metres). Since there are many different analog port sp
49、ecifications in use throughout the world, this Recommendation will not specify one. The E-DVA MUST have an analog port that conforms to appropriate National practices. An example of such a port is given in Appendix I. 8 Client requirement 8.1 Provisioning The E-DVA MUST comply with the E-DVA provisioning requirements as specified in RST E-UE-Prov. Rec. ITU-T J.460.2 (06/2008) 7 8.2 Security The security considerations for the E-DVA are based on those specified in PKT 33.203, PKT 23.228, PKT 24.229, and NFT TR. The requireme
