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Re: [HSSG] 40G MAC Rate Discussion

> What I'm getting at is also if there is a possibility to instead of 
> doing LAG, bundle four 10GBASE-T into a single 40G connection, ie 
> doing this multi-lane to leverage the development already done on the 
> PHYs (please correct me if I'm using the wrong terminology here).
> So basically what I'm getting at, can 4 10GBASE-T be turned into a 
> single 40G connection (not using LAG but something more close to what 

Yes, it can be done. 10GBASE-T is crunching bits, so if you
break up a frame into fragments, as proposed by APL, the
same 4x10GBASE-T PHYs will work just fine.

> This would mean that any requirement for 40G could be satisfied by 
> MUXing 4 10GE WANPHY into a single OC768, or 4*10GBASE-T.

Right, except that you will need a MAC that runs at 40Gb,
which is why we are having this discusssion. Otherwise
you are back to LAG.

> This would not be LAG (as LAG for me is doing per-flow load balancing) 
> but something done closer to the PHY (the same way XENPAK uses four XAUI).

See above. You can not run a single flow over multiple MACs.
This is not how networked applications work. By suggesting
that we do MUXing at the physical layer, you are advocating
for having a 40Gb Ethernet MAC, or in other words that we
should define 40Gb Ethernet. I would agree with that.