E-mail firewall with stored key encryption/decryption

Abstract

An e-mail firewall () applies policies to e-mail messages () between a first site and a plurality of second sites in accordance with a plurality of administrator selectable policies (). The firewall comprises a simple mail transfer protocol (SMTP) relay () for causing the e-mail messages () to be transmitted between the first site and selected ones of the second sites. A plurality of policy managers () enforce administrator selectable policies. The policies, such as encryption and decryption policies, comprise at least a first source/destination policy (), at least a first content policy () and at least a first virus policy (). The policies are characterized by a plurality of administrator selectable criteria (), a plurality of administrator selectable exceptions () to the criteria and a plurality of administrator selectable actions () associated with the criteria and exceptions. The policy managers comprise an access manager () for restricting transmission of e-mail messages () between the first site and the second sites in accordance with the source/destination policy (). The policy managers () further comprise a content manager () for restricting transmission of e-mail messages () between the first site and the second sites in accordance with the content policy (), and a virus manager () for restriction transmission of e-mail messages () between the first site and the second sites in accordance with the virus policy ().