[c-nsp] What is the lowest latency switch?

[Soon Lee]

Hi

Lowest latency switch hahaha.

according to this document(http://www.cisco.com/en/US/prod/switches/ps5718/ps6021/stac_report_cisco_catalyst_4900m_10gige_switch.pdf)

Latency of C4900M is 19 microseconds.

I'm looking for any other vender switch which is low latency switch.

If you guys inform me then I will test it with Smartbit or something like that.

And cisco says,

Examples of Cisco Low-Latency Layer 2 Switches
The Cisco Nexus 5000 Series access-layer switch is an example of a low-latency cut-through single-stage fabric implementation that will meet the requirements of all except ultra-low latency applications. The Cisco Nexus 5000 Series uses VOQs to minimize port contention.
Another platform that meets most low-latency application requirements is the Cisco Catalyst® 4900M Switch, a store-and-forward switch that fits in the data center access and distribution layers. The Cisco Catalyst 4900M uses a shared-memory architecture with an ultra-low-latency ASIC design.

http://www.cisco.com/en/US/prod/collateral/switches/ps9441/ps9670/white_paper_c11-465436.html

does it mean C4900M is lower latency switch than Nexus 5000 ?


Thanks

Soon Lee
CCIE# 17724

-----Original Message-----
From: Peter Rathlev [mailto:peter at rathlev.dk] 
Sent: Wednesday, March 16, 2011 6:09 PM
To: Soon Lee
Cc: cisco-nsp at puck.nether.net
Subject: Re: [c-nsp] What is the lowest switch?

On Wed, 2011-03-16 at 18:02 +0900, Soon Lee wrote:
> What is the lowest switch?

The one at the bottom of the rack? ;-)

> I heard C4900M is low latency switch
> 
> Do you know any other vender?
> 
> Please let me know.

I guess the standard Cisco answer to low latency would be the cut-through switching Nexus platform. Nexus 5000 would probably fit the description. The 4900 is (AFAIK) store-and-forward and thus has slightly higher forwarding latency.

Beware that the latency differences are quite small and most peoply have no need to the lower.

--
Peter