10GE TOR port buffers (was Re: 10G switch recommendaton)

Saku Ytti saku at ytti.fi
Fri Jan 27 16:55:15 UTC 2012

On (2012-01-27 17:35 +0100), bas wrote:
> Chassis:
> Juniper EX8200-8XS		512MB/10GE
> Cisco WS-X6708-10GE		32MB/10GE (or 24MB)
> Cisco N7K-M132XP-12		36MB/10GE
> Arista DCS-7548S-LC		48MB/10GE
> Brocade BR-MLX-10Gx8-X	128MB/10GE (not sure)
> 1GE aggregation.
> Force10 S60		1250MB shared
> HP 5830			3000MB shared

I'd take some of these with grain of salt, take EX8200-8XS, PDF 
indeed does agree:
Total buffer size is 512 MB on each EX8200-8XS 10-Gigabit
Ethernet port or each EX8200-40XS port group, and 42 MB
on each EX8200-48T and EX8200-48F Gigabit Ethernet port,
providing 50-100 ms of bandwidth delay buffering

However 512MB is about 400ms of buffering, while 512Mb is 50ms. So I think
JNPR PDF is just wrong.
Similar error may exist for some other quoted numbers.

But generally nice list, especially the 10GE fixed config looked realistic,
sometimes I wish we'd have 'dpreview' style page for routers and switches,
especially now with dozen or more vendors selling 'same' trident+ switch,
differentiating them is hard.


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