Q:

How to read network card specs

i am in the need of buying a rack server which will serve static video files to users. Each video file will be between 30MB and 50MB and we expect up to 16k concurrent users. I was looking for servers and i found some nice ones from HP and DELL but i am kinda lost when looking at the network card specs. I know that i will need about 2000Mbit uplink but i cant figure out how to read that out from the network card specs. And what the important values are.
Lets take this one:
Broadcom® NetXtreme II 57710 Single Port 10GBase-T NIC with TOE and iSCSI Offload, PCIe-8 
What does 10Gbase mean? 10Gbit? 10Gbyte? 
Well, maybe someone can enlighten me a bit :-)
P.S. The servers (approx. 5) will be placed in a huge server farm, so the bottleneck will definitly be my own hardware ;-)
P.S. OS - CentOS , NginX web server

A:

What does 10Gbase mean? 10Gbit? 10Gbyte?

You're reading only part of it. It's 10GBase-T. Let's break it down. 

10G - this means it's a 10Gbps card
Base - this means that it is a baseband transmission (standard stuff)
T - this means that the signal is carried over twisted pair cabling. You should use CAT 6A for this. 

Should i go for single port or dual port? Dual port is more cpu heavy probably?

Do you want redundancy through teaming/bonding? Do you need an aggregate of 20Gbps? The answers to these questions should answer your question. No one else can answer this for you. Obviously a second active NIC will have slightly more overhead, but in the grand scheme of things, it's not a lot. 

