Effectiveness and Limitations of E-Mail Security Protocols

Simple Mail Transport Protocol is the most widely adopted protocol for e-mail delivery. However, it lackssecurity features for privacy, authentication of sending party, integrity of e-mail message, nonrepudiationand consistency of e-mail envelope. To make e-mail communication secure and private,e-mail servers incorporate one or more security features using add-on security protocols. The add-onsecurity protocols provide a reasonable security but have several limitations. This paper discusseslimitations of e-mail security protocols, analyzes and evaluates their effectiveness in e-mail servers. Italso proposes methods to improve efficiency of e-mail servers in detecting spoofed e-mails from domainsthat do not follow any standard anti-spoofing protocol. Further, it presents results of studies carried outto appraise e-mail user practice; knowledge of security protocols and their confidence in e-mail system.