1、INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STAN DARD IZATI ON SECTOR OF ITU H.460.5 (1 1 /2002) SERIES H: AUDIOVISUAL AND MULTIMEDIA SYSTEMS Supplementary services for multimedia H.225.0 transport of multiple Q.931 information elements of the same type ITU-T Recommendation H.460.5
2、 ITU-T H-SERTES RECOMMENDATIONS AUDIOVISUAL AND MULTIMEDIA SYSTEMS CHARACTERISTICS OF VISUAL TELEPHONE SYSTEMS INFRASTRUCTURE OF AUDIOVISUAL SERVICES General Transmission multiplexing and synchronization Systems aspects Communication procedures Coding of moving video Related systems aspects SYSTEMS
3、AND TERMINAL EQWMENT FOR AUDIOVISUAL SERVICES SUPPLEMENTARY SERVICES FOR MULTIMEDIA M0BI”ITY 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 vali
4、d 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 Recommendation H.225.0 (2000), Call signalling protocols and media stream packetization for packet-based multime
5、dia communications systems. IT-T Recommendation H.323 (2000), Packet-based multimedia communications systems. ITU-T Recommendation 4.93 1 (1 998), ISDN user-network intevace layer 3 specifzcation for basic call control. - - Standard 5 3 Terms and definitions For the purposes of this Recommendation t
6、he definitions given in clause 3 of ITU-T Recs H.323, H.225.0 and H.245 apply. 4 The conversion procedure To transfer a 4.931 message containing multiple IEs of the same type over the H.225.0 protocol, the conversion specified in this clause shall be performed. The conversion applies to all IEs exce
7、pt for the IEs that have the first appearance of the particular E identifier. The binary representations (that includes IE identifier, length and content) of all such Es shall be assembled into a single octet string. The resulting octet string shall be used as the value of the GEF parameter, as defi
8、ned in clause 5, “Generic Data Parameter specification“. In accordance with ITU-T Rec. H.225.0, Es shall not be duplicated in the 4.93 1 part of the H.225.0 message. 5 Generic Data Parameter specification This clause defines the DuplicateIEs feature and parameter ITU-T Rec. H.460.5 (11/2002) 1 I Par
9、ameter name: I Esstring Parameter description: Parameter identifier type: Parameter identifier value: The binary representation of the 2 to last IEs of particular type. Standard 1 Parameter type: Parameter cardinality: 2 raw 1 ITU-T Rec. H.460.5 (1112002) SERIES OF ITU-T RECOMMENDATIONS Series A Ser
10、ies B Series C Series D Series E Series F Series G Series H Series I Series J Series K Series L Series M Series N Series O Series P Series Q Series R Series S Series T Series U Series V Series X Series Y Series Z Organization of the work of IT-T Means of expression: definitions, symbols, classificat
11、ion General telecommunication statistics General tariff principles Overall network operation, telephone service, service operation and human factors Non-telephone telecommunication services Transmission systems and media, digital systems and networks Audiovisual and multimedia systems Integrated ser
12、vices digital network Cable networks and transmission of television, sound programme and other multimedia signals Protection against interference Construction, installation and protection of cables and other elements of outside plant TMN and network maintenance: international transmission systems, t
13、elephone circuits, telegraphy, facsimile and leased circuits Maintenance: international sound programme and television transmission circuits Specifications of measuring equipment Telephone transmission quality, telephone installations, local line networks Switching and signalling Telegraph transmiss
14、ion Telegraph services terminal equipment Terminals for telematic services Telegraph switching Data communication over the telephone network Data networks and open system communications Global information infiastructure and Internet protocol aspects Languages and general software aspects for telecommunication systems Printed in Switzerland Geneva, 2003
