On Sun, 18 Jul 2010 21:07:36 -0400 Tim Durack <tdurack@gmail.com> wrote:
On Sun, Jul 18, 2010 at 8:01 PM, Brett Frankenberger <rbf+nanog@panix.com> wrote:
On Mon, Jul 19, 2010 at 07:13:46AM +0930, Mark Smith wrote:
This document supports that. If the definition of a software router is one that doesn't have a fixed at the factory forwarding function, then the ASR1K is one.
The code running in the ASICs on line cards in 6500-series chassis isn't fixed at the factory. Same with the code running on the PFCs in those boxes. There's not a tremendous amount of flexibility to make changes after the fact, because the code is so tightly integrated with the hardware, but there is some.
(Not saying the 6500 is a software-based platform. It's pretty clearly a hardware-based platform under most peoples' definition. But: the line is blurry.)
-- Brett
Surely the important point for most forwarding engines is that there is isolation between control, management and forwarding planes?
If I'm looking for a box, I want line rate forwarding on all interfaces. I want stateless ACLs and policing functions on the forwarding plane. I want to use those functions to protect the control and management planes. I want the control plane to cope with the required amount of forwarding state and churn. I want the management plane to be somewhat as capable as the Linux tools I run to maintain the network.
And that's the crux of the issue. Can the box survive if line rate maximum PPS is being aimed at it, either for forwarding or at the control plane? If the answer is yes, then whether it is a "software router" or "hardware router" is academic.
I don't honestly care whether it is a single cpu, multi-core multi-cpu, ASIC or NPU.
That being said, for the networks I help maintain, the C6K meets most of those requirements. I think the N7K is movement in the right direction. I consider both to be L2/L3 switches :-)
-- Tim:>