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

[Phil Mayers]

Tassos Chatzithomaoglou wrote:
> I think i haven't made it clear enough....
> 
> Let's suppose i have the following 2 systems:
> 
> 6500/SUP720-3BXL
> 6724-SFP (DFC-3CXL)
> 
> 6500/SUP720-3BXL
> 6724-SFP (DFC-3BXL)
> 
> If i'm not mistaken both will operate in 3BXL mode, so what is the disadvantage of the first one?

There is no disadvantage (unless you're worried about "immature" 
hardware, which I don't think is a valid concern here)

> 
> 
> Now, suppose i also have the following 2 systems:
> 
> 7600/RSP720-3CXL
> 6724-SFP (DFC-3CXL)
> 
> 7600/RSP720-3CXL
> 6724-SFP (DFC-3BXL)
> 
> If i'm not mistaken, the first one will operate in 3CXL, while the second one in 3BXL.
> So the first one would be better (in what terms? That is my secondary question).

Yes the first one would be better. Primarily it would have 96k mac table 
rather than 64k. I believe there are some bug-fixes in the PFC/DFC 3C 
but they're minor (I recall a CoPP related one).

The *main* think the -3C does above the -3B is VSS but obviously if 
you're on RSP720 that's not available.

It's possible there are loads of features squirrelled away inside the 
-3C but evidence is it's a pretty minor HW rev for the VSS support, and 
I presume Cisco are keen to stop making the -3B purely on cost reasons.

> 
> Generally, why should i choose 3BXL, when with a 3CXL i can have a 3BXL plus something more? That is my primary question.

You should not, is my understanding.