What are the advantages and disadvantages of using 10GBase-T vs. SFP+ Direct Attach to interconnect devices where distance is not a determining factor?
You'll find discussion of this elsewhere - see 'Why would I choose Copper over SFP+ for 10GbE?' - but broadly speaking SFP+ DA is, ignoring distance:
- Cheaper at the adapter side.
- Lower power and latency.
- Gives added flexibility if you need to move to fibre later.
10GBase-T on the other hand is:
- Cheaper at the connector side - patch leads being cheaper than SFP+ DA cables
- Somewhat easier to work with physically - SFP+ DA cables tend to be a bit thick, bulky and can be a pain to route through cable management in my experience, though to an extent this depends on type (passive vs. active) and manufacturer.
- More flexible in that the same cable plant can be used for 10/100/1000.
I've been watching the field for a while, and it doesn't seem like there's consensus on the "best" option yet - networking, server and adapter vendors seem to be hedging their bets.
For what it's worth, we went with SFP+ DA in a top-of-rack configuration, largely due to the ability to mix copper/fibre on the same device. Whether this is applicable for your environment will depend on the number of ports and nature of the network you're building.
One final point: if you do some reading on this, finding objective, unbiased opinion is hard - a lot of the commentary and claims are by people with vested financial interest in encouraging one or other option. As an example, compare and contrast: