IP & Sender Reputation: What is it, Why do you care and What is your rating?
Email Reputation seems to be all that anyone is talking about in the deliverability community (give it a few weeks/months and everyone will be on the engagement tip). The reason for all the fuss is that over the past year or so ISP’s and email providers have improved greatly the way they manage inbound email and work out how to classify mail as spam.
The old methods of simple blacklists and heuristic checking of content (treating your message as spam based on what words you used, how much HTML etc) are being replaced with a more holistic approach, looking at a number of factors that are based on your IP’s history online. The reason for this is spammers were finding a way to game the system and the old methods were simply no longer working. ISP’s have progressed to using a reputation based system that is tied to the history of the IP address you use to send email.
If you are serious about your commitments to best practice then Sender Reputation is good news for you as there really are no shortcuts and its almost impossible to game the system (‘almost’… because spammers usually find a way). The better the spam filters are the more likely your message is to be read (imho) as the recipient has less junk to deal with. So if you are an email marketer, the anti-spam fight is as much about your success as it is about the ISP managing its finite resources.
IP based reputation is a huge leap forward from the use of arbitary blacklists and hueristic checks, however there is still some way to go before reputation is based on domain names which will be yet another huge leap forward. That is the subject of another discussion.
What is IP or Email Sender Reputation?
Sender Reputation is based on how much you email (volume), the consistency of your sending patterns, complaint rates, bounces (unknown user rates), spam trap hits and content. When you send an email message this leaves your MTA (your outbound mailserver) and is handled by a recipient mailserver. Increasingly these mailservers are now using ‘reputation’ based decisions on how to handle your mail. Reputation means different things to different ISP’s, each looking at different elements of your sending history and applying different weight to various aspects. Essentially “IP Reputation” in terms of deliverability is your IP’s history online and how that translates depends on the complex series of algorithms used by various internet and email providers.
Why do you care?
Essentially your reputation dictates your deliverability and that is why you should care. Some of the reputation checks are performed at the point you try and deliver your message. If your history is not good with that ISP and your reputation is ‘poor’ based on its algorithms they may decide to simply refuse to accept your mail, others may limit how many messages you can send in a specified period of time.
Even if you get as far as sending the message and the recipient ISP accepting that message there may still be further checks that are performed, and these checks will decide whether your message goes to the inbox or the junk folder.
So your reputation is directly connected to your deliverability, without good IP reputation you cannot expect good deliverability. Hopeful you now understand the basics of IP reputation and understand why its critical to your success.
What is my IP Reputation?
As I said earlier your reputation is defined at an ISP level and therefore it is perfectly possible to have a good reputation with one ISP and a poor reputation with another. Luckily there are several major ISP’s and gateways that allow you to do some checking on your reputation and history. Because of the nature of how Sender Reputation is managed there is no single place to go to gauge your overall reputation. However I have collected the biggest and the best so it is relatively easy to identify what your reputation is with the ‘big boys’.
SendMail Reputation Tool
Trend Micro, Symantec, Sophos, Kaspersky, Avira and many other mail filters make use of SendMail Repuation data when decideding whether or not your message belongs in the spam folder.