The SPF protocol stands for “Sender Policy Framework“. The idea behind it is to ensure that only an allowed set of domains or IP addresses can send emails using the given domain.
Let’s say that your domain is example.com.
By adding an SPF policy to your domain, you will provide a list of all the domains, subdomains or IP addresses that are allowed to send an email using @example.com as the sender.
For instance, you can configure your SPF for your domain to look like this:
v=spf1 a mx include:mail.example.com ~all
This will allow your server
mail.example.com to be able to send emails that originate from @example.com. If another server tries to send an email that also seems to be originating from @example.com but is in fact not, they will be refused by the destination servers.
ImprovMX does not send emails. We forward them.
Since we forward emails, we are in fact the destination server in the example given above. For all the emails we receive, we first check if the SPF is valid, and then use another policy called SRS: “Sender Rewriting Scheme“.
When using ImprovMX, you don’t have to modify anything in your DNS configuration, we take care of this for you automatically. The same reasoning applies for DKIM and DMARC.
Any questions? Don’t hesitate to contact us.