Sender ID

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Sender ID For Email Deliverability

Sender ID is similar to SPF record except that it extends the verification process to include purported responsible addresses include in the header. SPF records are more widely deployed. It is used by MSN/Hotmail. An overview of Sender ID can be found on record can be found on Microsoft's Site.

Similar to SPF record a Sender ID record is used to validate email addresses, publishes policy records in DNS, and uses the same syntax for its policy records. By concerning itself with the header it differs in its approach to what it uses to validate an incoming mailing. SPF records use the tag “v=spf1” in its syntax for Sender ID varies depending on the policy it used to address. Sender ID records can use “spf2.0/pra”, “spf2.0/mfrom”, or “spf2.0/mfrom,pra”. mfrom stands for mail from, the envelope sender that SPF record checks for , and publishers of senderder policies wishing to protect their address in MAIL FROM Return –Paths generally prefer the classic v=spf1 format to the later proposed spf2.0/mfrom.

Sender ID uses a tricky evaluation of four mail header fields:

  • From
  • Sender
  • Resent-From
  • Resent-Sender

Which header is validated is selected according to an algorithm known as the PRA (Purported Responsible Address). The algorithm tries to find the email address that is responsible for sending the message. The pra attempts to tackle the problem of phishing while SPF tries to counter the problem of spam bounces and other auto-replies to forged Return-Paths. They propose different solutions for different problems.

How to setup Sender ID

We strongly suggest to use the following wizard and follow their instructions for setting up Sender ID.