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By Mike Anstey

This was my second time attending an ITU-T standards meeting. This one was a Plenary meeting and my previous attendance had been at the interim meeting in France. There was definitely a different feeling to this meeting, especially at the beginning, largely due to the fact that there were more participants at the opening meeting; each country's delegates were grouped together and it felt as if we had a truly global collaboration for the purpose of helping to define the future of the telecom industry. Of course, once these early meeting formalities were concluded, it was down to business as usual.

Up until a short time before this meeting, the debate over Generic Mapping Procedure (GMP) had been in full gear and a decision on which type of GMP to use had not been made. This topic had been central to most of the discussion at the interim meeting in France and many expected the debate to continue in Geneva. However, shortly before the Plenary meeting, Cortina, who had been proposing a GMP solution with fixed stuff distribution, decided to withdraw their proposal and agree to the sigma-delta based solution. Cortina's concession was good news. G.709 Amendment 3 could be now appropriately edited and reviewed with this GMP solution and we would most likely arrive at a consensus on the amendment by the end of the Plenary meeting. By the end of the meeting we had consented to the amendment, although there were a number of other items that we debated and discussed.

There was considerable discussion concerning the language and description of multi-stage ODU multiplexing in the G.709 document. On one hand, G.709 allows for multi-stage multiplexing such as ODU0 to ODU1 to ODU2 to ODU3 to ODU4. However, the delegates generally agreed that any more than 2 stages of multiplexing within one equipment domain results in increased complexity, which translates to increased cost. The question was, should text be included in this document to "suggest" the number of desirable multiplexing levels? We decided to leave the G.709 text as generic as possible, and agreed that it will be up to users and implementers figure out what makes the most sense.

For 40GE and 100GE mapped over OTN, the standard was reworked to allow for section BIP-8 monitoring, and additional text was added to the appendix to clarify some details of these mappings. A new feature was also added to G.709 to allow for round-trip delay measurements at the path layer and the CnD for GMP has been changed to a 10bit value with a CRC-5. There were also discussions on Black Link and FEC, GPON over OTN and OTN timing transparency however, no key changes to G.709 were required for these items.

Geneva itself is an incredible city, with its beautiful scenery and fabulous restaurants and pubs. I enjoyed jogging by Lake Geneva and visiting the old part of town. I shared many nice meals with other attendees and the weather was absolutely perfect. I look forward to my next trip there and will likely take a trip into the Alps.