I’m currently involved in a few projects which offer web based services to the many on the street, and I’m always interested in finding more efficient and cost effective methods of powering these sites, so recently I’ve been looking at Amazons EC2.
I fully understand the advantage of EC2 for short run computing tasks where processing power may only be needed for a few days or weeks, but I was looking to see if EC2 is an effective platform for a web service which is going to be running 24x7x365, and in my opinion the answer is quite simply No.
The reason behind this is very simple; Bandwidth Costs.
Bandwidth to a website is the same as roads are to a bricks and mortar business, it’s how your customers get to you, the speed at which people can use roads & bandwidth affect how likely they are to return, and the more bandwidth & roads you have coming to you the more people can get to you at the same time.
If you look at the various hosting packages available from big service providers in the US like 1&1 you’ll usually see around 500GB of bandwidth included with their basic virtual private server packages which costs US$ 29.00 per month. If you compare this to EC2 using Amazons own AWS calculator you’ll see that having 45GB inward from the visitor and 455GB outwards to the visitor (a total of 500GB) will cost US$ 81.85, thats means the bandwidth costs alone on EC2 are nearly three times the cost of the entire package from 1&1.
If you move up the offerings from 1&1 the comparison with EC2 gets even more concerning. For 100 GB of inward bandwidth and 1115GB of outward bandwidth you can get a server package from 1&1 which offers an Athlon 64 X2 4200+ server with 2GB of Ram, 250GB of storage, 250GB of FTP accessible backup space, a dedicated SSL certificate, access to your machines console if the OS networking fails , AND over twice the transfer bandwidth (3000 GB).
If you want resiliency, you can also rent two servers of a lesser spec (Athlon64 3500+, 1GB Ram, 160GB storage, 160GB backup, and an SSL cert for each server) from 1&1 and each one will still have more transfer bandwidth than EC2 offered (2000GB per server from 1&1 against 1215GB from EC2).
So if you’re starting up a company based around a 24×7 web service you may well find that EC2 is not the way for you.
Note : Prices and specifications correct as of 3rd September 2008.