Which is faster: Cloudfront or S3?

Amazon Web Services’ S3 can be a pretty good and cheap approach to webhosting, serving files at a cost of  cents per 1000 hits.

How much of an improvement would it be to serve these files out of Amazon’s Cloudfront, the content delivery service that caches content around the world?

Here are the results of a brief experiment. In the month of June I served a 1.3 Megabyte sound file both from S3 and from Cloudfront to the WatchMouse monitoring network. I then measured the minimum time to connect, as well as the average download time for the two, and compared those across the locations from where they were downloaded.

The next table shows the minimum connect times in milliseconds.

Country	City	Cloudfront	S3
Ireland	Dublin	0	0
United Kingdom	Glasgow	1	12
Netherlands	Amsterdam	0	14
France	Lille	5	18
Belgium	Antwerp	4	21
Germany	Muenchen	6	31
Italy	Padova	5	43
U.S.A.	Chicago	2	102
U.S.A.	Austin	5	120
U.S.A.	San Francisco	2	150
Brazil	Sao Paulo	0	202
Australia	Melbourne	12	319

What is noticeable is that the connect time to the S3 service increases with the geographical distance from Ireland, which is where the main file is hosted. The connect time to S3 is much more constant and a lot lower. This is good for web users waiting for their webpage to build up.

The following table shows the average download times in milliseconds.

Country	City	Cloudfront	S3
Ireland	Dublin	181	343
United Kingdom	Glasgow	535	614
Netherlands	Amsterdam	388	657
France	Lille	284	1029
Belgium	Antwerp	406	882
Germany	Muenchen	277	947
Italy	Padova	582	1488
U.S.A.	Chicago	402	2589
U.S.A.	Austin	516	3291
U.S.A.	San Francisco	341	5426
Brazil	Sao Paulo	269	5082
Australia	Melbourne	1769	6325

Again, we see that the S3 download times correlate with distance, and Cloudfront download times being much more constant across the world, as well as being consistently lower.

From a business perspective, it makes sense to use Cloudfront as it will deliver a better user experience, but be aware that Cloudfront costs can be between a bit smaller than S3 costs and up to two times higher.