Overview of DKIM

• Cryptography-based protocol, signs selected header fields and message body

• • Merge of DomainKeys (Yahoo!) and IIM (Cisco)
  • Merge created by an industry consortium
  • Significant industry support (see dkim.org for a list)

• Intended to allow good senders to prove that they did send a particular message, and to prevent forgers from masquerading as good senders (if those senders sign all outgoing mail)

• Not an anti-spam technology by itself