Thread Links | Date Links | ||||
---|---|---|---|---|---|
Thread Prev | Thread Next | Thread Index | Date Prev | Date Next | Date Index |
[BCCâ??ed STDS-802-3-CU4HDD@xxxxxxxxxxxxxxxxx (backplane) to inform, but not to spam them further]  Dear Arthur,  2.5G/5G is in TF review (in prep for WG ballot in July â?? with hope that is), closing EoW. It would be good for your position to be known consistently on both â??T and â??K.  Yong.  From: Arthur Marris [mailto:arthurm@xxxxxxxxxxx]  William,   If the vast majority of people all agree that having 2.5G Ethernet (in all its various and future forms) support link fault signalling is the right thing to do then fair enough. My concern is that this has slipped in un-noticed and people are not aware of the extra requirement.    Also I am not sure that 2.5GBASE-T â??needsâ?? link fault signalling. My understanding is that it is unnecessary for 2.5GBASE-T but is required for 10GBASE-T and possibly for 5GBASE-T.  Arthur  From: William Lo [mailto:williaml@xxxxxxxxxxx]  Hi Arthur,  I would have preferred to simply take the 1G PCS, RS, and MAC and simply scale it to 2.5G. However 802.3bz chose to scale down 10G RS and MAC for 2.5G. I don't think it is a good idea to have RS attached to one kind of PHY not support link fault signaling while supporting it in another when both PHYs are operating the same speed.  Note that 802.3cb could simply scale down 10GBASE-R to 2.5G and avoided all this link fault signaling issue but didn't. We are aware of the scaled up 1000BASE-X solutions in the field for 2.5G and crafted something something that will allow legacy solutions to be compatible (see annex 127B) and yet align to the decisions that 802.3bz task force has made.   I do not think it is justified to ask 2.5GBASE-T to disable something that it needs simply for the sake that some legacy non-IEEE sped up version of 1000BASE-X, RS, MAC can't handle fault signaling. If there is a market demand to connect up this legacy interface to 2.5GBASE-T there are vendor specific workarounds that can be applied.  Thanks, William
|