CloudFlare - Cloudflare is a global network designed to make everything you connect to the Internet secure, private, fast, and reliable.
Sucuri - Website Protection, Malware Removal, and Blacklist Prevention
Myra Security - The Myra Security-as-a-Service platform monitors, analyzes, and filters malicious internet traffic before virtual attacks can do any real harm.
Amazon CloudFront - Amazon CloudFront is a content delivery web service.
Altospam - Antispam and antivirus software on Cloud
DDoS-GUARD - DDoS protection for websites and networks. CDN included.