QA interview at Big Switch Networks

In general know your osi stack, tcp/ip, vlans, various test tools used for testing networking gear etc. if you can walk an l2/l3 packet across and know how a packet header changes or does not change, vpns - all types etc. prepare with a mindset of deploying a complex corporate network and you will be fine.

I couldn't agree more. I cleared it & this is all what one needs to know to ace it.