Does email have a guarantee of delivery?

A client asked me earlier this week what SLAs ISPs provided for email delivery. The short answer is that there isn’t a SLA and that the only guarantee is that the email will get there when it gets there.
But as I was mentioning this to Steve, he pointed out that there was a recent change in the RFCs for email. In both RFC 821/2 and RFC 2821/2 (the original email related RFCs and the update in the early 2000’s) the RFCs stated that once a receiving MTA accepted an email that that MTA was required to either delivery the mail or generate an asynchronous bounce. While this isn’t a standard SLA, it does mean that a 2xy response after DATA meant the email would either be delivered to the user or be sent back to the sender. Despite the RFC requirements some receivers would still drop mail on the floor for various reasons, sometimes intentionally and sometimes not.
RFC 5321/2, the current SMTP standard, still says that once a server accepts the mail it must not lose that mail ‘for frivolous reasons.’ The RFC goes on to admit, though, that in recent years, SMTP servers are under a range of attacks and dropping mail on the floor is not frivolous in those cases.
 

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Delivery and marketing part 2

A while ago I wrote some thoughts about the conflicting requirements of delivery and marketing. I posted something similar over on the Only Influencers list, too. My thoughts generated a very interesting discussion, one that helped me clarify some of my somewhat random thoughts from earlier.
Marketing is about finding mindshare. One way you get mindshare is repetition. But people tune out repetition pretty quickly. Sending the same offers, the same copy over and over again means recipients start to tune things out.  When recipients start tuning out mail, they may not bother opening it, they just read the subject line.  If too many recipients start relying on the subject line then delivery can suffer.
Effective marketing relies on getting mail in front of the target audience. That’s the delivery component. Without inbox delivery, even the best marketing will not work.
No one will see marketing if it is in the spamfolder.
I don’t think you can cleanly separate delivery strategy from marketing strategy, but it’s important to realize they have different constraints and different pressures. When I talk about delivery with a client, I’m talking about getting mail into the inbox. And, most of the time, they’ve come to me because they’re not getting into the inbox and they have to make changes. The genius of their marketing is irrelevant, because no customers see it.
But once mail is in the inbox you can’t just ignore delivery, either. Sure, it becomes less of a pressure on the copy and the marketing strategy, until such time as the mail isn’t getting into the inbox any longer. Then it’s back to working on delivery and maybe having to implement some aggressive data hygiene. Back in the inbox and you can be aggressive on the marketing again.
Successful email marketing requires balancing the constraints of good delivery against the constraints of good marketing.

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Emails that make you smile

This summer’s non-work project for me has been training for a 5K run with Fleet Feet in Menlo Park. As part of the training programs we get weekly emails from the store on Monday. As I was reading through today’s email, I found myself smiling and happy. Lisa, who is one of the store owners and writes the emails, is just so happy and bouncy and thrilled to share her love of running and that comes through in the newsletter.
Our group’s primary coach is the other store owner. During runs we often talk about random stuff, and when I tell people I do email delivery, they always start talking about their experience with email and spam. One night I was running with Jim, and we were talking about Jim’s experiences with sending email. He mentioned their ESP and talked about how convenient it was. But then he mentioned he wasn’t sure that they were sending enough mail (which made me laugh hard enough I almost tripped on a curb).
I realized I am not just a delivery expert when I started thinking about all the ways they could increase the amount of email they send, while still maintaining the quality and the friendly feel of their bulk emails. What could they offer local runners that would increase the value of the store to them? The first very obvious thing was a race calendar. There are dozens of local races every week, telling folks about upcoming races and entry deadlines would be a way to contact folks regularly without it always being a “buy stuff from us!!”
What commercial emails have you gotten recently that have made you smile?

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Email is store and forward

Many of us are so used to email appearing instantaneous, we forget that the underlying protocol was never designed for instant messaging. When the SMTP protocol was originally proposed it was designed to support servers that may have had intermittent connectivity. The protocol allowed for email to be spooled to disk and then sent when resources were available. In fact, almost everyone who was around more than 10 years ago knows of a case where an email took weeks, months or even years to deliver.
These days we’re spoiled. We expect the email we send to friends and relatives to show up in their mailbox within moments of sending it. We expect that sales receipt or e-ticket to show up in our mailbox within instants of a purchase. We expect that our ISPs will get us email immediately, if not sooner.
But there are a lot of things that can slow down email delivery. At several points in the process an email may be spooled to disk. It stays on the spool until the next part of the delivery process can happen. Other points of slowdown include the various anti-spam, anti-virus and anti-phishing protections that ISPs must implement. Then add in the extreme volume of email (around 10 billion messages a day) and all of a sudden email delivery is slower than many senders and recipients expect it to be. This delay is not ideal, but the system is designed so that mail is not silently discarded.
While individual emails may be delayed, most users will rarely see that delay in the email that they send. Bulk senders, who may be sending thousands or hundreds of thousands of emails a day, may see more delays in a single send than the average user sees in years of sending one-to-one email.
Email is store and forward, not instant. Sometimes that means there is a delay in getting email into the recipients inbox. And, sometimes there isn’t anything anyone can do to speed up delivery, except to adjust expectations of how email works.

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