Mar
31
By George Bilbrey
President
Complaint rates are a major driver of anti-spam systems. A high complaint rate (number of "this is spam" reports relative to messages in the inbox) is known to drive bad delivery rates for commercial mailers.
One of the more interesting problems that I've run across at Return Path is trying to figure out why complaint rates for the same IP address (or domain) vary so widely across different ISPs. Here is a scatter chart of complaint rates for ~2,500 commercial email marketing IPs across two different ISPs. In this graph 0.05 = 5% complaint rate (5 messages per 100 places in the inbox).
What is apparent is:
So what might cause the variation in complaint rates? A partial list would include ...
Tell me moreCategories: Email Deliverability
Mar
30
John Young, PhD
Director of Product Analytics
Return Path's Sender Score reputation rank (available at www.senderscore.org) is a measure of the reputation of mail coming from an IP address based on feedback from many ISPs and filtering companies that provide reputation data to Return Path (over 150 million mailboxes). As regular readers of this blog know, the major driver of inbox placement is reputation. But saying that is one thing - actually understanding your sending reputation is another. We created the Sender Score to give senders a number that would help them quantify their reputation to make it easier to understand and therefore easier to manage.
Does it work? We decided to do a little test to find out.
Our findings: Yes, it does work. ...
Tell me moreCategories: Email Deliverability
Mar
24
by J.D. Falk, Director of Product Strategy, Receiver Services
Throughout this series of articles we've been talking about DKIM, and what a valid DKIM signature actually means.
Part 1 explained that the DKIM "d=" value identifies the domain name which signed the message, which may be different from the author of the message. Part 2 described how the author domain can gain some control over whether any other domain name should ever sign a message purporting to be From: that author domain. Part 3 discussed how the reputation of a d= domain leads to a reliable determination of trustworthiness, while part 4 reminded us that truth cannot be assumed until trust is certain.
What this means for senders (of any type) is that ...
Tell me moreCategories: Email Deliverability
Mar
23
by J.D. Falk, Director of Product Strategy, Receiver Services
Once you've determined that you can trust the signer of a message, as we discussed in part 3, it's easy to extrapolate that various portions of the message are equally trustworthy. For example, when there's a valid DKIM signature, we might assume that the From: header isn't spoofed. But in reality, DKIM only tells us two basic things:
DKIM uses a cryptographic signature based on a hash of the message, so if the signature is valid, we also know that the message wasn't changed in any way between the time it was signed and the time the signature was verified. What we don't know, and can't know, is what happened -- intentionally or unintentionally -- before it was signed.
For example, I could write a message where I claim to be Joshua Norton, Emperor of these United States and Protector of Mexico. It'll be signed when I send it to you. But DKIM doesn't tell you if it's true ...
Tell me moreCategories: Email Deliverability
Mar
17
by J.D. Falk, Director of Product Strategy, Receiver Services
Last year, MAAWG published a white paper titled Trust in Email Begins with Authentication, which explains that authentication (DKIM) is "[a] safe means of identifying a participant-such as an author or an operator of an email service" while reputation is a "means of assessing their trustworthiness."
Regular readers of this blog already know that reputation systems based on IP addresses, including our Sender Score, are used by many ISPs and anti-spam vendors to determine which mail to accept, which to reject, and which to subject to additional filtering before making a delivery decision. There, the identifier is the IP address.
The reason this sort of reputation works for delivery decisions is that it's an attempt to measure whether the sender of a message can be trusted to send mail that the recipients want -- or, more accurately, whether the IP address of a message can be trusted to send mail that the recipients won't complain about. We also mix in the concept of safety, largely in the form of how likely it is that the IP address is sending phishing scams or similar bad stuff. ...
Tell me moreCategories: Email Deliverability
Mar
16
By Melinda Plemel
Receiver Relationship Manager
In our ongoing quest to champion inbox standards and make email better we have just launched a feedback loop for Time Warner Cable's Road Runner service. We are very excited to be expanding our partnership with Road Runner by offering a service that will reduce customer complaints and filtering errors.
As a special benefit to our clients, this service has been available to Return Path clients for the past month. It is now available for the rest of the email universe at: http://feedback.postmaster.rr.com.
As one of the top five mailbox providers in the United States, Time Warner Cable's Road Runner will be an extremely valuable feedback source. This follows in a long line of Return Path sponsored feedback loops including ...
Tell me moreCategories: Email Deliverability
Mar
12
by J.D. Falk, Director of Product Strategy, Receiver Services
In part 1, we explained that the DKIM "d=" value identifies the domain name which signed the message, which may be a different domain name from the author of the message.
Tying the signing and author domains together requires an additional standard: Author Domain Signing Practices (ADSP). In IETF parlance, the "author domain" is the domain name in the From: header, so ADSP is a way for the author domain to publish a statement specifying whether any other domain name should ever sign a message purporting to be From: that author domain....
Tell me moreCategories: Email Deliverability
Mar
10
By Matt Blumberg
CEO & Chairman
Return Path friend and investor Fred Wilson has a post on his blog today about his recent mission to unsubscribe from unwanted email. He mentions the oft-cited myth that clicking unsubscribe links will result in more spam. While this was never true of legitimate companies, it was, and still may be true of scammers, phishers and other bad actors.
Those of us in the email space just get this, right? But Fred's blog is a good reminder that most consumers don't. They don't have the time or the inclination to decide - on the fly, with hundreds of messages stacked up like jets over LaGuardia, demanding attention now! - if this email is from a legitimate company, and therefore safe to unsubscribe from or not.
How did we get to this sorry state of affairs? A few ways, actually. ...
Tell me moreCategories: Email Deliverability
Our new episode of Reputation Radio is available now on iTunes.
In this episode we have just one segment -- a fun, free-wheeling discussion with Todd Herr the Postmaster at Time Warner Cable. Todd talks about the challenges he faces as postmaster at one of the country's top internet service providers, how he views sender reputation and what the email universe looks like from his side of the desk. Todd is very smart and very funny -- this is definitely a can't-miss episode.
Is there someone in the email universe you think we should interview? Do you have a question about email deliverability or sender reputation>? ...
Tell me moreCategories: Email Deliverability
Mar
09
by J.D. Falk, Director of Product Strategy, Receiver Services
DomainKeys Identified Mail (DKIM) is the leading email authentication technology, supported by major ISPs including Google, AOL, and Yahoo! (who invented its predecessor), popular mail server software like Sendmail, and many of the best minds in email technology. But if you peruse the archives of the IETF DKIM mailing list, or start up a conversation at MAAWG, it might appear that there's still a lot of disagreement about what a DKIM signature actually means.
Often, anyone attempting to describe authentication turns to analogies: a driver's license, or a license plate on a car, or a passport -- all saying that you are who you say you are, but not (by themselves) proving that you're trustworthy. The trust measurement is external to DKIM: a reputation score, or third-party certification status.
But what, exactly, is being trusted? What's being measured? ...
Tell me moreCategories: Email Deliverability
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