Cisco Email Security VS Proofpoint

Barracuda Email Security Gateway - Barracuda's Email Security Gateway is a powerful antivirus filter specifically designed to identify and eliminate email-borne threats, stopping hazards before they reach the network.

Mimecast Gateway - Mimecast Gateway is a SaaS-based email security solution that uses sophisticated, multi-layered detection engines and intelligence to protect email data and employees from malware, spam, advanced threats and zero-day attacks.

Symantec Email Security.cloud - Symantec Email Security.cloud provides always-on, inbound and outbound email security against malware, targeted attacks, and advanced threats

dmarcian - Safeguard your email from abuse

Proofpoint Email Security and Protection - Learn about Proofpoint's email security solutions that protect organizations against threats such as email fraud, phishing, spam, bulk email, and viruses.

Hornetsecurity - Hornetsecurity offers you comprehensive, integrated managed e-mail security services.