Hardware-based e-mail screening gateways can handle a higher volume of e-mails than their software brethren. These appliances sit between your router and mail servers (or can replace your mail servers).
8e6 ES2000
Notable features: Rules based on user groups. "White lists" of acceptable addresses or domain names. Content filtering. Attachment filtering.
Ciphertrust IronMail
Notable features: Distributed signature networks. Weighted keyword filtering and header analysis. Heuristics-based inspection. Reverse DNS lookup and local deny lists.
Escom ASMTP Appliance
Notable features: Company's ASMTP technology runs as a proxy server daemon on Linux. Handles both SMTP and Extended SMTP messages.
IronPort A50
Notable features: Delivers over 500,000 messages per hour. Monitors top domains by recipients in queue. Multiple alert events. Logs mail, system, NTP and FTP events.
eighted keyword filtering and header analysis. Heuristics-based inspection. Reverse DNS lookup and local deny lists.
Escom ASMTP Appliance
Notable features: Company's ASMTP technology runs as a proxy server daemon on Linux. Handles both SMTP and Extended SMTP messages.
IronPort A50
Notable features: Delivers over 500,000 messages per hour. Monitors top domains by recipients in queue. Multiple alert events. Logs mail, system, NTP and FTP events.
McAfee WebShield e500
Notable features: Scans SMTP, HTTP, FTP, and POP3. SSL Web-based console for remote management. Content and attachment filtering. Supports DNS-based black hole lists.
Mirapoint MD300 Internet Message Director
Notable features: Outbound message content filtered to enforce corporate policies. Can be managed via HTTPS Web interface, command line interface (CLI), or Java GUI. Integrates with LDAP servers.
Vircom VOP modusMail Enterprise
Notable features: High capacity secure messaging server. Sieve-based anti-spam filter. Anti-virus scan engine.
