Gotcha. With SFP+ I think the only nod to backward compatibility would be 1gbit RJ-45 SFPs, which can get a little spendy in large numbers (although so can DACs). As for distance, I admit I haven't encountered any DACs longer than 15 meters (~49 feet) -- not that I'm positive they don't exist. Jima On Mon, Oct 1, 2012 at 2:10pm, Andreas Echavez wrote:

Mostly backwards compatibility; simplicity. We're planning for some super-high-density virtualization/storage projects mixed in with lower bandwidth gear, and sticking to one type of cable for everything would be convenient. I thought DAC had some distance limitations as well.

This is all speculation though, I don't have any personal experience with the 10Gbase-T stuff either. I have no idea what to expect performance-wise.

-A

On Mon, Oct 1, 2012 at 12:58 PM, Jima <nanog@jima.tk> wrote:

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Does anyone here have experience running copper 10Gbase-T networks? It seems like the standard just died out. For us it would make a lot of sense for our applications -- even if throughput and latency aren't as great. If anyone out there knows of any *copper* 10 gig-t switches (48 port?), I'd be interested to hear your experiences. I can't seem to find any high-density ones from major vendors.

Is there something unique about your environment that wouldn't allow you to use 10gbit SFP+-based switches with DAC (Direct Attach Copper) cables? Those seem fairly well supported.

Jima