CloudFlare is one of, if not the largest CDN company in the world. Their free plan provides you with their CDN, caching and basic DDoS protection. You’ll have to upgrade to a paid account if you want access to their advanced features, including better front-end security for your website.

You could combine their free account to take advantage of the DDoS protection with one of the better CDNs listed below.

If you pick up hosting from my recommendation above, BlueHost, you can get CloudFlare for free as part of your hosting package.