[c-nsp] New Catalyst 6k chassis

[Tom Hill]

On 2013-06-27 08:44, Chris Welti wrote:
> For those interested in the technical details, the slides for
> BRKARC-3486 are up at:
> http://t.co/ZncyGrhHX9
>
> Slide 24 seems to indicate that the current Sup2T can support
> 440G/slot using higher clock frequencies for the fabric connections
> and 4 instead of 2 fabric connections per linecard.
> I guess the magic number 880G/slot can be achieved using two parallel
> sup2T in one chassis simultanously (in analogy to the ASR9K line).
> Of course that still needs new linecards, to make any use of it. I'm
> hoping for a 4x100GE line-rate card by Spring 2014.

I've been "told" that 880G will need a new Supervisor.

440G will be like RSP440 in the ASR9K: you will need dual SUP2T to take 
advantage of it. With a single Supervisor & the other changes, you'll 
have 220G per slot.

(My understanding -- correct me if I'm wrong, please!)

When using SUP2T in 6513-E, you have 11 slots with 2x40G traces each 
(80G/slot, 880G total). In 6807-X their distribution is condensed to 5 
slots with 4x40G traces each (160G/slot, 800G total) *but* the extra two 
are wired to the other supervisor, so you need to run active/active 
(a-la ASR9K).

To get to 220G, you're looking at the higher SerDes frequencies on the 
fabric traces. What you get will depend on the (future) line cards you 
buy, I imagine:

  @55G = 110G/slot on single sup, 220G with dual sup (550G/1100G total)
  @110G = 220G/slot on single sup, 440G with dual sup (1100G/2200G 
total)

To confuse it further, there are another four fabric traces in there 
that can't be utilised by SUP2T. That's where the new supervisor is 
needed, in order to then get to 880G/slot.

I'm quite annoyed that there aren't any newer line cards announced that 
take advantage of faster SerDes rates (as your existing X6800/X6900 
series line cards will not run any faster) but then I seem to recall 
6500-E came a short while before PFC4/EARL8 was announced too.

Even so, it's an interesting upgrade. C6K really seems to be the 
'cross-over' between the other two products it competes against now. I 
can certainly see truth in what ytti says. :)

Tom