I am looking for recommendations for hardware specs for a server that needs to be a web cache for a user population of about 2,000 concurrent connections. The clients are viewing segmented HTTP video in bitrates ranging from 150kbps to 2mbps. Most video is "live" meaning segments of 2-10 secs each, of which 100 or so are maintained at a time. There are also some pre-recorded fixed length videos. How would I go about doing the provisioning calculation for such a server: What kind of HDD (SSD?), how many NICs how much RAM etc? I am thinking of using Varnish on Linux, all the RAM I can get my hands on, 2 CPUs with 6-8 cores each.