SC-02-12 meeting, London, 2010-05

Report of the the meeting of the SC-02-12 Working Group on Audio Applications of Networks of the SC-02 Subcommittee on Digital Audio held in conjunction with the AES 128th Convention in London UK, 2010-05-22

The meeting was convened by chair R. Foss.

The agenda and the report of the previous meeting held in New York, 2009-10-11, were accepted as written.

Open projects

AES58-R: Review of AES58-2008: AES standard for digital audio - Audio applications of networks - Application of IEC 61883-6 32-bit generic data
Scope: to describe unique requirements for professional audio carried over 1394.

Status: No action requested or required
Intent: Review, Initiated: 2008, Target: 2013
Current goal: Status report, Goal date: continuing

There was no discussion about this project.

AES-R10: AES standards project report - Use cases for networks in professional audio
Scope: to identify and clarify use cases for networks in professional audio applications for Recording, Live sound, and Installations Current

Status: No action requested or required
Project intent: Review; Initiated: 2008-08-25; Target date for completion: 2013
Current goal: Status report; Target date for goal: continuing

The IEEE1722.1 working group has an interest in this report. It is a published report, and Foss will inform them that they can download it.

Development projects

AES-X075: Liaison with IEC TC100 for IEC 61883
Scope: Prepare recommendations and assist the work of IEC TC100 regarding the development and maintenance of relevant parts of IEC 61883. Any assigned task group shall report project progress to SC-02-12 and shall ask SC-02-12 for its advice on content. Administrative review of the project shall follow AESSC rules.

Status: Continuing
Project intent: Liaison; Initiated: 1998; Target date for completion: Continuing
Current goal: Status report; Target date for goal: Continuing

J. Yoshio provided a liaison report that encompassed work performed in the 1394TA and IEC with regard to the A/M protocol (now at version 2.2) and IEC 61883-6 (which derives from the A/M protocol, and which is now on edition 3.0). In particular, these updates were performed in response to a requirement for the transmission of the 8 channel audio data of Blu-Ray disc. The solution was to use the MBLA (Multi-Bit Linear Audio) format. Yoshio-san's report has been uploaded to the document site as "x075-liaisonreport-100525.pdf".

AES-X132: Synchronization of audio over IEEE 1394
Scope: to specify methods of audio clocking and sampling-frequency synchronization in a professional audio network based on the IEEE 1394 high performance serial bus. Include techniques to ensure devices function correctly in a network which includes IEEE 1394.1 compliant bridges

Status: Proposed to retire this project

It was decided to leave the document associated with this project on the document site in its currrent format, and to retire this project.

AES-X137: Liaison with 1394 Trade Association (1394 TA)
Scope: Liaison with 1394 Trade Association (1394 TA)

Current status:
Continuing Project intent: Liaison; Initiated: tba; Target date for completion: Continuing
Current goal: Status report; Target date for goal: Continuing

There was no liaison report, although it was noted that some 1394TA information was provided within the AES-X075 report, relating to the A/M protocol.

AES-X170: Integrated Control, Monitoring and Connection Management for Digital Audio and other Media Networks
Scope: The objective of this project is to create and standardize: 1. A set of structured Internet Protocol-based messages that can be used to control single parameters or groups of parameters, and to monitor these parameters. The parameters are associated either with typical signal processing functionality within audio devices, synchronization between such devices, or connections between such devices. 2. A mechanism for grouping of device parameters, and messages required to implement such grouping. 3. A mechanism for the control of latency within networks of audio devices, and a specification of the messages and parameters required for the control of such latency. 4. Parameter modifiers, and the messages required to create and configure such modifiers. 5. Security levels, and the messages required to set and get such levels.

Assigned to: SC-02-12, Status: Revised draft on doc site for working-group comment
Intent: Standard, Initiated: 2010-04-29, Target: 2010
Current goal: PTD, Goal date: 2010-05

It was noted that there were no comments on the two draft documents placed on the document site in December 2009. An updated document was placed on the document site in April 2010. There will be a call for comments on this document, and a 4 week period allowed for comments. After this, a word document should be made available for secretariat formatting.

AES-X192 Audio over IP interoperability
Scope: The goal is to standardize the format for audio data within IP packets. Currently there are a number of ways of transmitting uncompressed audio over IP. There are even a number of ways of transmitting audio using RTP.

Status: PIR received
Intent: Standard initiation Target: 2010
Goal: PIR, Goal date: 2010-06

An initial PIR was received from K. Gross. The PIR is incomplete, and further information regarding the PIR is required before the project can be formalized. There was some discussion about this project, in particular liaisons with interoperability work within the EBU (EBU 3326 was an example). There were a number of questions related to the goals of this project.


Liaison with AVB - There was no report from M. Mora, however P. Foulkes reported on the status of the various AVB-related standards. Foss provided information about the IEEE 1722.1 working group.

Liaison with ESTA: P. Nye provided a report on ESTA activities. The working group went through this report, with a particular focus on ACN and its various components. There was a request to provide the ACN documents on the SC-02-12 document site.The report has been placed on the SC-02-12 document site as "ESTALiason-Nye-100525.pdf".

Liaison with MPEG - J. Grant discussed MPEG Media Transport (MMT) for streaming, and MPEG file format designed for random access. He discussed a move to combine these two. He described various forms of compression to cater to differing play out capabilities. He provided information on HTTP streaming, and referred the group to the MPEG site for further information. There will be a meeting at the end of July in Geneva.

Further liaisons: P. Stevens introduced the possibility of a liaison with the EBU. There are a number of 'expert communities'. Peter pointed the group to the appropriate communities. The working group decided to create a new liaison and to have Stevens responsible for this liaison. Grant indicated his willingness to provide a liaison with the IEC 62379 working group. Grant provided some information about the current status of IEC 62379. Stevens provided information about IEC 62379 part 7, which has to do with media measurement throughout a network.

New Projects:

There were no further projects. However, there was an extended discussion about protocol interoperability. Stefan Heinzman proposed the idea of multiple protocols, where devices might implement more than one protocol, and at the end of the day manufacturers would decide what mix of protocols to incorporate. S. Harris discussed the DLNA consortium that encompassed a number of protocols, and provided precise interoperability guidelines for these various protocols in the consumer space. DLNA provides profiles for manufacturers, and have a certification scheme whereby a product can be sent for testing and acquisition of the DLNA 'label'. The working group proposed a project to create interoperability guidelines. The importance of manufacturers and users being part of the group was stressed, and to request contribution for this effort from TC-NAS. The final goal of this project would be a standard that indicated requirements for interoperability. It was pointed out that project AES-X192 was already addressing the issue of interoperability over IP by determining standard formats for IP transmission. However, interoperability recommendations need to extend to other transports and also to control mechanisms. It was agreed to continue the discussion on the reflector.

New business:

There was no new business.

The next meeting will be scheduledin conjunction with the AES 129th Convention in San Francisco, CA., USA, 2010-11.

AES - Audio Engineering Society