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

bas kilobit at gmail.com
Fri Jan 27 17:30:35 CST 2012


Hi,

> The margin on a top-of-rack switch is very low.  48 port gige with
> 10GE uplinks are basically commodity boxes, with plenty of competition.
> Saving $100 on the bill of materials by cutting out some buffer
> makes the box more competitive when it's at a $2k price point.

The list of 10GE TOR switches I sent earlier are list from $20K to $100K
So actual purchase cost for us would be $10K to $30K
$500 for some (S)(Q)(bla)RAM shouldn't hold back a vendor from
releasing a bitchin switch....

Again this argument does not explain why there are 1GE aggregation
switches with deep buffers..

> Also, as was pointed out to me privately, it is also important to loook
> at adaptive queue management features.  The most famous is WRED, but
> there are other choices.  Having a queue management solution on your
> routers and switches that works in concert with the congestion control
> mechanism used by the end stations always results in better goodput.
> Many of the low end switches have limited or no AQM choices, while the
> higher end switches with fancier ASICs can default to something like
> WRED.  Be sure it is the deeper buffers that are making the difference,
> and not simply some queue management.

All true... Still no reason why not to offer a deep buffer TOR...



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