Spam is a major bottleneck issue that the email marketing industry faces on a daily basis. Fraudsters often try to forge the sender address of emails and try to perform malicious activities. The only way to protect your emails and improve deliverability is by implementing email authentication. Sender Policy Framework (SPF) is an authentication technique that helps receiving email servers identify legitimate email senders and prevent spam entering the inbox of email recipients.
How SPF works
SPF allows an email sender to publish the list of IPs from which emails will be sent on their behalf. When we send email campaigns, the receiving server of the mailbox provider will perform a TXT record DNS lookup for the return-path domain. As a result, an SPF record will be returned. The SPF record will contain the list of IP addresses that are authorized to send emails on our behalf. When the IP address that was used to send the email campaign is present in that list, the email will pass SPF validation.
More about the SPF record
- SPF is a “path-based” authentication system
- An SPF record is a unique DNS TXT record
- The record contains a list of IP addresses published by an email sender
Decoding an SPF record value
Sample SPF record:
v=spf1 include:zcsend.net include:sender.zohobooks.com ~all
- v: This indicates the version of SPF that's being used.
- include: The include statements asks the receiving servers to include the SPF records of the specified domain. In our scenario, since the domain will be zcsend.net, its SPF records will looked up. The SPF records contain the set of IP addresses through which emails are being sent.
- ~all: When SPF fails, "all" will decide how receiving servers should handle the email. At Zoho Campaigns, we generally use the "Soft fail" approach. When SPF fails, the email will be accepted but tagged as a "Soft Fail."
Benefits of implementing SPF
Implementing SPF will help us fight email spoofing. It also earns the trust of mailbox providers. This will help you improve deliverability as major mailbox providers prefer offering inbox placement for emails from an authenticated sender domain.
At Zoho Campaigns, we set up SPF for all of our users. All you need to do is copy the SPF value and paste it into your domain hosting website. Marketers need to understand that implementing SPF alone will not safeguard emails. To improve deliverability and protect your sender domain and emails from phishing and spoofing attacks, we recommend you implement DKIM and DMARC along with SPF.
Click
here to learn how to set up an SPF record for your sender domain.