eMail spoofing is becoming very common these days. Nearly all abusive e-mail messages carry fake sender addresses. The victims od email spoofing, whose addresses are being abused often suffer from the consequences, because their reputation gets diminished and they have to disclaim liability for the abuse, or waste their time sorting out misdirected bounce messages. To help prevent this sort of abuse, it is recommended to add SPF record as well as DKIM to publish yourself and your identity.
We recommend that you create a Sender Policy Framework (SPF) record for your domain. An SPF record is a type of Domain Name Service (DNS) record that identifies which mail servers are permitted to send email on behalf of your domain. The purpose of an SPF record is to prevent spammers from sending messages with forged From addresses at your domain. Recipients can refer to the SPF record to determine whether a message purporting to be from your domain comes from an authorized mail server.
DKIM is a kind of digital “signature” added to the header of mail messages sent from your domain. Recipients can check the domain signature to verify that the message really comes from your domain and that it has not been changed along the way.
Set up DKIM
DKIM helps to verify the sender and integrity of a message. It allows an email system to prove that a message was not altered during transit (meaning it is not forged), and that the message came from the specified domain.
Set up SPF
SPF attempts to prevent spammers from sending email while forging your domain’s name as the sender (email spoofing). This authentication function works by adding IP addresses to a list, specifying computers that are authorized to send mail from your domain(s). It verifies that messages sent from your domain(s) are coming from the listed server, reducing the amount of back scatter you receive.
These are the ways to publish in the mail that the mail is not spoofed and you are not forging any ones’ email ID in your mail.
So what happens if some one else does it ? i.e. some one puts some email ID in the Reply To header and sends some junk email to a hundred thousand email IDs ? There will be a lot of bounces and there are chances that your email ID will get black listed. If you are getting a lot of bounces or your mail server is processing a lot of bounce mails, you must be alerted.
Basically having DKIM and SPF can only help you tell others that the mail has originated from the from the correct source. It is not spoofed – it will help the mail servers to deliver the mails to the inbox than in Junk.