[c-nsp] DFC-3C vs DFC-3CXL

[Brandon Bennett]

On Mon, Jan 26, 2009 at 12:49 PM, Marlon Duksa <mduksa at gmail.com> wrote:

> Hi - Can someone tell me what is the exact difference between line cards,
> for example ES20 for 7600, with DFC3C and the XL version of the same?
> Is it only a DDRAM or is it something else? I know that the
> scaling numbers are higher on the XL version of the cards but not sure if
> there is anything else on those cards except the memory that makes it
> larger? Or is it TCAM? Whatever it is, it looks to me that it is only the
> external memory in question and nothing inherent to the chips (EARL for
> example)..


The difference si the same as a Sup720 (or RSP) with a PFC3C or PFC3CXL.
It's all about the size of the routing table.  The DFC3C can only hold aprox
256K routes (this will vary based on your configuration/defaults etc).  The
DFC3CXL can hold approx 1M routes (again check the TCAM configuration guide
on how to allocate TCAM amongst protocols).

All DFCs/PFCs will run at the lowest common demonitor.  So If you have a
RSP720-PFC3CXL and a ES20 with a DFC3C in it the entire system will be
limited to the TCAM size of the DFC3C.

Also if you are buying new, please look into the ES20+ which has many
improvements over the ES20.

-Brandon Bennett