1、 International Telecommunication Union ITU-T H.248.42TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (03/2009) SERIES H: AUDIOVISUAL AND MULTIMEDIA SYSTEMSInfrastructure of audiovisual services Communication procedures Gateway control protocol: DCME interworking package Recommendation ITU-T H.248.42
2、 ITU-T H-SERIES RECOMMENDATIONS AUDIOVISUAL AND MULTIMEDIA SYSTEMS CHARACTERISTICS OF VISUAL TELEPHONE SYSTEMS H.100H.199 INFRASTRUCTURE OF AUDIOVISUAL SERVICES General H.200H.219 Transmission multiplexing and synchronization H.220H.229 Systems aspects H.230H.239 Communication procedures H.240H.259C
3、oding of moving video H.260H.279 Related systems aspects H.280H.299 Systems and terminal equipment for audiovisual services H.300H.349 Directory services architecture for audiovisual and multimedia services H.350H.359 Quality of service architecture for audiovisual and multimedia services H.360H.369
4、 Supplementary services for multimedia H.450H.499 MOBILITY AND COLLABORATION PROCEDURES Overview of Mobility and Collaboration, definitions, protocols and procedures H.500H.509 Mobility for H-Series multimedia systems and services H.510H.519 Mobile multimedia collaboration applications and services
5、H.520H.529 Security for mobile multimedia systems and services H.530H.539 Security for mobile multimedia collaboration applications and services H.540H.549 Mobility interworking procedures H.550H.559 Mobile multimedia collaboration inter-working procedures H.560H.569 BROADBAND, TRIPLE-PLAY AND ADVAN
6、CED MULTIMEDIA SERVICES Broadband multimedia services over VDSL H.610H.619 Advanced multimedia services and applications H.620H.629 IPTV MULTIMEDIA SERVICES AND APPLICATIONS FOR IPTV General aspects H.700H.719 IPTV terminal devices H.720H.729 IPTV middleware H.730H.739 IPTV application event handlin
7、g H.740H.749 IPTV metadata H.750H.759 IPTV multimedia application frameworks H.760H.769 IPTV service discovery up to consumption H.770H.779 For further details, please refer to the list of ITU-T Recommendations. Rec. ITU-T H.248.42 (03/2009) i Recommendation ITU-T H.248.42 Gateway control protocol:
8、DCME interworking package Summary The DCME Package is used for interfacing digital circuit multiplication equipment (DCME). DCME types are for instance defined by Recommendations ITU-T G.763, G.767 or G.768. There is a signalling interface defined between DCME and a so-called “international switchin
9、g centre“ (ISC). Recommendation ITU-T Q.50 defines such an interface. The DCME Package scopes DCME with Q.50 interfaces. This revision of Recommendation ITU-T H.248.42 adds new parameters for events, to allow the media gateway controller (MGC) to resynchronize itself in the event it loses track of t
10、his state. Source Recommendation ITU-T H.248.42 was approved on 16 March 2009 by ITU-T Study Group 16 (2009-2012) under Recommendation ITU-T A.8 procedure. ii Rec. ITU-T H.248.42 (03/2009) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field
11、of telecommunications, information and communication technologies (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
12、 telecommunications on a worldwide basis. The World Telecommunication 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
13、 the procedure laid down in WTSA Resolution 1. In some areas of 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 bo
14、th a telecommunication administration and a recognized operating 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
15、all of these mandatory provisions are met. The words “shall“ or 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
16、RIGHTS ITU draws attention to the possibility that the practice 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
17、 ITU members or others outside of the Recommendation development 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 th
18、is may not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2010 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU
19、-T H.248.42 (03/2009) iii CONTENTS Page 1 Scope 1 2 References. 2 3 Terms and definitions . 2 4 Abbreviations 2 5 DCME interworking package . 3 5.1 Properties 3 5.2 Events . 4 5.3 Signals 13 5.4 Statistics 15 5.5 Error codes 15 5.6 Procedures 15 Bibliography. 20 Rec. ITU-T H.248.42 (03/2009) 1 Recom
20、mendation ITU-T H.248.42 Gateway control protocol: DCME interworking package 1 Scope The DCME Package is used for interfacing digital circuit multiplication equipment (DCME). DCME types are for instance, defined by b-ITU-T G.763, b-ITU-T G.767 or b-ITU-T G.768. There is a signalling interface define
21、d between DCME and a so-called “international switching centre“ (ISC). ITU-T Q.50 defines such an interface. The DCME Package scopes DCME with Q.50 interfaces (see Figure 1). NOTE 1 Relation to PCME b-ITU-T G.765: the DCME package may be applied in principle as well for PCME types with Q.50-based CM
22、E signalling and E1/PDH trunk interface types. The final decision is still for further studies, e.g., due to dependencies with the still open clause 19 of b-ITU-T G.765 on dynamic load control. NOTE 2 Relation to IP-CME b-ITU-T G.769: the DCME package may be applied for IP-CME types with Q.50-based
23、CME signalling and E1/PDH trunk interface types. Other trunk facilities are for further study. H.248.42(09)_F01Media Gateway (MG) Gateway controlprotocolH.248.1Media gateway controller(MGC)Gateway controlprotocolH.248.1Digital CircuitMultiplicationEquipment(DCME)e.g., G.763, G.767,G.768International
24、 switching centre (ISC)Q.50H.248.42DCME packageTransmission layer:G.704 E1/PDHFigure 1 Scope of the DCME Package The DCME Package must support DCME-ISC signalling interface functions. The required Package capabilities may be summarized by the following overview from b-ITU-T G.763 and ITU-T Q.50. The
25、re are three major groups of functions: Transmission resource management Facilitates the dynamic load control process within the ISC and the DCME concurrently, based on the status of the traffic loading on the DCME system. Seizure/release of 64 kbit/s circuits Used in the DCME for the generation of
26、internal assignment and disconnection messages and in the ISCs for the validation of circuit seizure selection/release based on acknowledgement from the DCME. 2 Rec. ITU-T H.248.42 (03/2009) Maintenance information Facilitates information exchange between the DCME and the ISCs pertaining to the main
27、tenance status. Maintenance status information may be exchanged between the DCME and the ISC. 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the time of publication, the
28、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 Recommendations and other references listed below. A list of the currently
29、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. ITU-T G.704 Recommendation ITU-T G.704 (1998), Synchronous frame structures used at 1544, 6312, 2048, 8448 and 44 73
30、6 kbit/s hierarchical levels. ITU-T H.248.1 Recommendation ITU-T H.248.1 (2005), Gateway control protocol: Version 3, including its Amendment 1 (2008). ITU-T H.248.8 Recommendation ITU-T H.248.8 (2005), Gateway control protocol: Error code and service change reason description. ITU-T H.248.33 Recomm
31、endation ITU-T H.248.33 (2005), Gateway control protocol: PCM frame spare bit package. ITU-T Q.50 Recommendation ITU-T Q.50 (2001), Signalling between Circuit Multiplication Equipment (CME) and International Switching Centres (ISC). 3 Terms and definitions None. 4 Abbreviations This Recommendation u
32、ses the following abbreviations: 2PTY Two-Party 3PTY Three-Party C2C Circuit-to-Circuit C2P Circuit-to-Packet CAS Channel Associated Signalling CME Circuit Multiplication Equipment CSN Circuit-Switched Network DCME Digital Circuit Multiplication Equipment DS Dual Seizure IP-CME CME optimized for IP-
33、based networks ISC International Switching Centre MG Media Gateway MGC Media Gateway Controller Rec. ITU-T H.248.42 (03/2009) 3 MPTY Multiparty NGN Next Generation Network NROR No Response On Release OoS Out of Service P2P Packet-to-Packet PCM Pulse Code Modulation PCME Packet Circuit Multiplication
34、 Equipment PSN Packet-Switched Network RDSD Remote DCME Signalling Disabled SNOT Seizability NOT yet enabled TDM Time Division Multiplexing TRM Transmission Resource Management TS Time-Slot UKLS UnKnown Line State 5 DCME interworking package Package Name: DCME Interworking package Package ID: dcme (
35、0x009e) Description: This package defines the H.248 signals and events for a decomposed international switching centre (ISC) following ITU-T Q.50. The intention of this package is to be independent of ITU-T Q.50 Annexes A and B implementation. The H.248 MG provides PCM30 ITU-T G.704 compliant 2 Mbit
36、/s interface(s), whereas time-slot 16 is used to carry the ISC-DCME signalling protocol. The “term PCM30“ is defined in clause 3.1 of ITU-T H.248.33. Version: 2 Extends: None 5.1 Properties 5.1.1 DCME protocol Property Name: DCME Protocol Property ID: cmeprotocol (0x0001) Description: The specific p
37、rotocol (ISC DCME) supported for a 2 Mbit/s interface. Note that the MG shall provision this property for the physical termination representing time-slot 16. For the other physical terminations of the 2 Mbit/s interface, this is optional. Type: Enumeration Possible values: “None“ (0x0001) “Q50AnnexA
38、“ (0x0002) “Q50AnnexB“ (0x0003) 4 Rec. ITU-T H.248.42 (03/2009) Default: Provisioned Defined in: TerminationState Characteristics: read 5.2 Events 5.2.1 No trunk(s) available for 3.1 kHz audio or speech Event Name: Trunk unavailable Event ID: tunav (0x0001) Description: Generated when no bearer capa
39、city for additional 3.1 kHz audio or speech trunk(s) is available. This event is used by the DCME transmission resource management (TRM). 5.2.1.1 EventDescriptor parameters 5.2.1.1.1 Strict Transition Parameter Name: Strict Transition Parameter ID: strict (0x0001) Description: Indicates how the trun
40、k unavailable event is to be detected. Type: Enumeration Optional: Yes Possible values: “exact“ (0x0000): Only an actual transition to trunk unavailable is to be recognized. “state“ (0x0001): The event is to be recognized either if the DCME state transition is detected or if the DCME state is alread
41、y trunk unavailable. Default: “exact“ 5.2.1.2 ObservedEventsDescriptor parameters 5.2.1.2.1 Initial State Parameter Name: Initial State Parameter ID: init (0x0002) Description: The reason for reporting the trunk unavailable event. Only returned if the Strict Transition parameter is set to “state“. T
42、ype: Boolean Optional: Yes Possible values: “True“: The DCME state was already trunk unavailable when the Events Descriptor containing this event was activated. “False“: An actual state transition to trunk unavailable was detected. Default: “False“ Rec. ITU-T H.248.42 (03/2009) 5 5.2.2 No channels(s
43、) available for 3.1 kHz Event Name: Channel unavailable Event ID: cunav (0x0002) Description: Generated when no bearer capacity for additional 3.1 kHz channel(s) is available. This event is used by the DCME transmission resource management (TRM) to retain backward compatibility only and is not to be
44、 used in implementations based on 1993 or later versions of ITU-T Q.50. 5.2.2.1 EventDescriptor parameters 5.2.2.1.1 Strict Transition Parameter Name: Strict Transition Parameter ID: strict (0x0001) Description: Indicates how the channel unavailable event is to be detected. Type: Enumeration Optiona
45、l: Yes Possible values: “exact“ (0x0000): Only an actual transition to channel unavailable is to be recognized. “state“ (0x0001): The event is to be recognized either if the DCME state transition is detected or if the DCME state is already channel unavailable. Default: “exact“ 5.2.2.2 ObservedEvents
46、Descriptor parameters 5.2.2.2.1 Initial State Parameter Name: Initial State Parameter ID: init (0x0002) Description: The reason for reporting the channel unavailable event. Only returned if the Strict Transition parameter is set to “state“. Type: Boolean Optional: Yes Possible values: “True“: The DC
47、ME state was already channel unavailable when the Events Descriptor containing this event was activated. “False“: An actual state transition to channel unavailable was detected. Default: “False“ 5.2.3 Trunk(s) available for 3.1 kHz audio or speech Event Name: Trunk available Event ID: tav (0x0003) D
48、escription: Generated to notify the end of “No trunk available for 3.1 kHz audio or speech“ condition. This event is used by the DCME transmission resource management (TRM). 6 Rec. ITU-T H.248.42 (03/2009) 5.2.3.1 EventDescriptor parameters 5.2.3.1.1 Strict Transition Parameter Name: Strict Transiti
49、on Parameter ID: strict (0x0001) Description: Indicates how the trunk available event is to be detected. Type: Enumeration Optional: Yes Possible values: “exact“ (0x0000): Only an actual transition to trunk available is to be recognized. “state“ (0x0001): The event is to be recognized either if the DCME state transition is detected or if the DCME state is already trunk available. Default: “exact“ 5.2.3.2 ObservedEventsDescriptor p
