1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationDigital audio Digital input-output interfacing Transmission of digital audio over asynchronous transfer mode (ATM) networksBS EN 62365:2009Licensed Copy: Wang Bin, ISO/EXCHANGE C
2、HINA STANDARDS, 23/07/2010 07:35, Uncontrolled Copy, (c) BSINational forewordThis British Standard is the UK implementation of EN 62365:2009. It is identical to IEC 62365:2009. It supersedes BS EN 62365:2005 which is withdrawn.The UK participation in its preparation was entrusted to Technical Commit
3、teeEPL/100, Audio, video and multimedia systems and equipment.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisions of acontract. Users are responsible for its correct application. BS
4、I 2010ISBN 978 0 580 63672 1ICS 33.160.30 35.200Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of the StandardsPolicy and Strategy Committee on 30 April 2010.Amendments issued since publicationAmd. No. Date Text
5、 affectedBRITISH STANDARDBS EN 62365:2009Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 23/07/2010 07:35, Uncontrolled Copy, (c) BSIEUROPEAN STANDARD EN 62365 NORME EUROPENNE EUROPISCHE NORM July 2009 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisat
6、ion Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: Avenue Marnix 17, B - 1000 Brussels 2009 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 62365:2009 E ICS 35.200; 33.160 Supersedes EN 6236
7、5:2005English version Digital audio - Digital input-output interfacing - Transmission of digital audio over asynchronous transfer mode (ATM) networks (IEC 62365:2009) Audionumrique - Interface numrique dentre-sortie - Transmission de laudionumrique sur les rseaux mode de transfert asynchrone (ATM) (
8、CEI 62365:2009) Digitalton - Digitale Ein-/Ausgangsschnittstellen - bertragung von Digitalton ber ATM-Netzwerke (IEC 62365:2009) This European Standard was approved by CENELEC on 2009-06-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions
9、for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three of
10、ficial versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical co
11、mmittees of Austria, Belgium, Bulgaria, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the U
12、nited Kingdom. BS EN 62365:2009Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 23/07/2010 07:35, Uncontrolled Copy, (c) BSIEN 62365:2009 2 Foreword The text of document 100/1517/FDIS, future edition 2 of IEC 62365, prepared by technical area 4, Digital systems interfaces and protocols, of IEC
13、 TC 100, Audio, video and multimedia systems and equipment, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 62365 on 2009-06-01. This European Standard supersedes EN 62365:2005. The main changes with respect to EN 62365:2005 are listed below: second, third and fourth
14、 required formats in 4.3 removed; 4.3 reformatted, eliminating Table 2, and subsequent tables renumbered. The following dates were fixed: latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2010-03-01 latest dat
15、e by which the national standards conflicting with the EN have to be withdrawn (dow) 2012-06-01 Annex ZA has been added by CENELEC. _ Endorsement notice The text of the International Standard IEC 62365:2009 was approved by CENELEC as a European Standard without any modification. In the official vers
16、ion, for Bibliography, the following note has to be added for the standard indicated: IEC 60027-2 NOTE Harmonized as EN 60027-2:2007 (not modified). _ BS EN 62365:2009Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 23/07/2010 07:35, Uncontrolled Copy, (c) BSI 3 EN 62365:2009 Annex ZA (normati
17、ve) Normative references to international publications with their corresponding European publications The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the ref
18、erenced document (including any amendments) applies. NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies. Publication Year Title EN/HD Year IEC 60958-1 - 1)Digital audio interface - Part 1: General EN 60958-1 2008 2)IEC 609
19、58-4 - 1)Digital audio interface - Part 4: Professional applications (TA4) EN 60958-4 2003 2)ITU-T Recommendation I.150 - 1)B-ISDN asynchronous transfer mode functional characteristics - - ITU-T Recommendation I.363.5 - 1)B-ISDN ATM Adaptation Layer specification: Type 5 AAL - - ITU-T Recommendation
20、 Q.2931 - 1)Digital Subscriber Signalling System No. 2 - User-Network Interface (UNI) layer 3 specification for basic call/connection control - - 1)Undated reference. 2)Valid edition at date of issue. BS EN 62365:2009Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 23/07/2010 07:35, Uncontroll
21、ed Copy, (c) BSI 2 62365 IEC:2009(E) CONTENTS INTRODUCTION.6 1 Scope.8 2 Normative references .8 3 Terms and definitions .8 4 Format of audio data in ATM cells 10 4.1 Format of audio samples .10 4.1.1 Subframes.10 4.1.2 Audio sample word 10 4.1.3 Ancillary data 10 4.1.4 Protocol overhead .10 4.2 Pac
22、king of sample data into cells 12 4.2.1 Packing schemes 12 4.2.2 Temporal grouping 12 4.2.3 Multi-channel.12 4.2.4 Grouping by channel13 4.3 Formats.13 4.4 ATM adaptation layer 13 4.5 ATM-user-to-ATM-user indication 13 5 Switched virtual circuits 14 5.1 Addresses .14 5.2 Audio call connection: SETUP
23、 and ADD PARTY messages .14 5.2.1 Restrictions on connection requests 14 5.2.2 Information elements in the SETUP and ADD PARTY messages .14 5.2.3 Destination response to SETUP and ADD PARTY messages.15 5.3 Call disconnection .16 6 Coding of audio formats .16 6.1 Qualifying information16 6.2 Subframe
24、 format17 6.3 Packing of subframes into cells .17 6.4 Sampling frequency.18 7 Permanent virtual circuits .18 8 Management interface 19 8.1 Call connection: SETUP messages .19 8.1.1 Restrictions on connection requests 19 8.1.2 Information elements in the SETUP message 19 8.1.3 Destination response to
25、 SETUP message20 8.2 Message encapsulation .20 8.3 Message format and action to be taken by recipient 20 8.4 Message types 21 8.4.1 Messages sent from the controlling entity 21 8.4.2 Messages sent to the controlling entity23 8.4.3 Vendor-specific messages.25 Annex A (informative) Data protection26 A
26、nnex B (informative) Application identifier values.28 BS EN 62365:2009Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 23/07/2010 07:35, Uncontrolled Copy, (c) BSI62365 IEC:2009(E) 3 Bibliography29 Table 1 Fields contained in a subframe10 Table 2 Default port number and packing for certain VCI
27、s19 Table 3 Status enquiry message 21 Table 4 Audio connection request message .22 Table 5 Audio disconnection request message.22 Table 6 Input port status message .23 Table 7 Output port status message.24 Table 8 Other status messages25 Table 9 Vendor-specific messages.25 Table A.1 Sequence number
28、protection field values.26 Table B.1 Application identifier (octets 9 to 12) values in the BHLI IE 28 BS EN 62365:2009Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 23/07/2010 07:35, Uncontrolled Copy, (c) BSI 6 62365 IEC:2009(E) INTRODUCTION This International Standard describes means for t
29、he transmission of professional audio across digital networks, including metropolitan- and wide-area networks, to provide the best performance with regard to latency, jitter, and other relevant factors. Current-generation wide-area communications are based on two very similar systems, synchronous op
30、tical network (SONET) and synchronous digital hierarchy (SDH), SONET being used in the United States and SDH in Europe. On top of them are run integrated services digital network (ISDN), asynchronous transfer mode (ATM), and Internet protocol (IP). ISDN provides telephone call connections of a fixed
31、 capacity that carry one 8-bit value per 125 s; when a call is set up, its route through the system is chosen, and the switches that route the data are configured accordingly. Each link, between switches or between switch and end equipment, is formatted into frames that take 125 s to transmit, and e
32、ach data byte is identified by its position in the frame. ATM, also called broadband ISDN, provides a service similar to ISDN, but with the capacity of each call being specified by the caller. Links are formatted into cells, which consist of a header and 48 data bytes; the header is typically 5 byte
33、s long, and most of it is taken up with the virtual channel identifier (VCI) that shows to which call the cell belongs. Call set-up, routeing, and switching are done in the same way as in ISDN, but with calls not being restricted to 1 byte every 125 s. IP provides a very different service, not desig
34、ned for continuous media such as audio and video. There is no call set-up, and each packet contains enough information within itself to allow it to be routed to its destination. This means that the header is much larger than in the case of ATM, typically 74 bytes, and packets will also typically be
35、much larger, if only because otherwise the overheads would be excessive. Each packet is liable to be routed separately, so two packets that are part of the same flow may well take different routes. This can mean that the one that was sent first does not arrive first. For many professional audio appl
36、ications, a round-trip time from the microphone through the mixing desk and back to the headphones of no more than 3 ms is required. Allowing 0,5 ms each for conversion from analog to digital and back again, it follows that the network connections to and from the mixing desk must have a latency of l
37、ess than 1 ms each. For distances of more than about 200 km, the transmission delay alone will exceed 1 ms, but within a metropolitan area the transmission delay should be no more than 0,25 ms (equivalent to about 50 km), leaving 0,75 ms for packetization, queuing within switches, and resynchronizat
38、ion within the receiving equipment. Packetization delays are proportional to the size of the transmission unit (frame, cell, or packet), and resynchronization delays depend on how evenly spaced the transmission units are when they arrive at their destination. Both classes of delay are thus small for
39、 ISDN and large for IP. Using the format specified in this standard to carry dual-channel IEC 60958-4 audio with a 48 kHz sampling frequency over ATM results in an inter-cell time of 125 s, at which ATM will have similar delays to ISDN. A higher sampling frequency or a larger number of channels woul
40、d reduce the inter-cell time and hence also the delays. The queuing time within each ISDN switch is likely to be around one frame time or 125 s. The ATM documents limit the queuing time in an ATM switch to approximately the inter-cell time for the call, which, as with the other delays, translates in
41、to performance similar to that of ISDN for dual-channel 48 kHz IEC 60958-4 audio and better for higher sampling frequencies or larger numbers of channels. The queuing time within an IP router for normal, best effort, Internet traffic is unbounded, and if the router is congested, packets may simply b
42、e thrown away. Resource reservation protocol (RSVP) (see Annex A) allows capacity to be reserved for a particular traffic flow, but it does BS EN 62365:2009Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 23/07/2010 07:35, Uncontrolled Copy, (c) BSI62365 IEC:2009(E) 7 not guarantee that the pa
43、ckets will actually be routed over the links on which the capacity has been reserved; if the flow is re-routed, it will only get a best effort service until a reservation has been made on the new route, and it may not even be possible to make a reservation on the new route at all. ATM has therefore
44、been chosen as providing a more convenient service than ISDN and significantly better performance than IP, even when RSVP is used. This standard does not specify a physical interface to the network because one of the features of ATM is its ability to make a seamless connection between interfaces ope
45、rating at a wide variety of data rates and with different ways of encoding the ATM cells. Commonly used interfaces provide 25,6 Mbit/s over category 3 structured wiring and 155,52 Mbit/s over category-5 structured wiring or fibre-optic cable. The physical layer section description and unique ATM abb
46、reviations can be found in ATM forum approved specifications. See the Bibliography. BS EN 62365:2009Licensed Copy: Wang Bin, ISO/EXCHANGE CHINA STANDARDS, 23/07/2010 07:35, Uncontrolled Copy, (c) BSI 8 62365 IEC:2009(E) DIGITAL AUDIO DIGITAL INPUT-OUTPUT INTERFACING TRANSMISSION OF DIGITAL AUDIO OVE
47、R ASYNCHRONOUS TRANSFER MODE (ATM) NETWORKS 1 Scope This International Standard specifies a means to carry multiple channels of audio in linear PCM or IEC 60958-4 format over an ATM layer service conforming to ITU-T Recommendation I.150. It includes a means to convey, between parties, information co
48、ncerning the digital audio signal when setting up audio calls across the ATM network. It does not specify the physical interface to the network. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition ci
49、ted applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60958-1, Digital audio interface Part 1: General IEC 60958-4, Digital audio interface Part 4: Professional applications (TA4) ITU-T Recommendation I.150: B-ISDN asynchronous transfer mode functional characteristics ITU-T Recommendation I.363.5, B-ISDN ATM Adaptation Layer specification: Type 5 AAL ITU-T Recommendation Q.2931: Digital Su
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