Google Apps administrators can now enable DKIM signing for all outgoing messages which helps validate outbound mail as being from that domain.
To add a digital signature to outgoing mail, you generate a domain key that Google Apps uses to create encrypted mail headers that are unique to your domain. You add the public key to the Domain Name System (DNS) records for your domain. Recipients can then verify the source of a mail message by retrieving your public key and using it to decrypt the header.
How to access what’s new:
There are three major steps required to add the DKIM signature to all outgoing mail:
– Generate the domain key for your domain
– Add the public domain key to the DNS records for your domain
– Turn on authentication in the ‘Advanced Tools’ section of the administrator control panel
Note: If you purchased your domain from one of our registration partners while signing up for Google Apps, the first two steps are not necessary. Google will automatically generate the domain key and add the necessary DNS record when you turn on authentication.
For more information: