Email

Running DNSBLs in an IPv6 World

DNS blacklists for IPv4 addresses are now nearly 15 years old, and DNSBL operators have gathered a great deal of expertise running them. Over the next decade or two mail will probably move to IPv6. How will running IPv6 DNSBLs differ from IPv4? There aren't any significant IPv6 DNSBLs yet since there isn't significant unwanted IPv6 mail traffic yet (or significant wanted traffic, for that matter), but we can make some extrapolations from the IPv4 experience. more

IPv6 DNS Blacklists Reconsidered

I opined about a year ago that DNS blacklists wouldn't work for mail that runs over IPv6 rather than IPv4. The reason is that IPv6 has such a huge range of addresses that spammers can easily send every message from a unique IP address, which means that recipient systems will fire off a unique set of DNSBL queries for every message... Now I'm much less sure this will be a problem... more

Greylisting Still Works - Part II

In my last post I blogged about greylisting, a well-known anti-spam technique for rejecting spam sent by botnets. When a mail server receives a an attempt to deliver mail from an IP address that's never sent mail before, it rejects the message with a "soft fail" error which tells the sender to try again later. Real mail senders always retry, badly written spamware often doesn't. I found that even though everyone knows about greylisting, about 2/3 of IPs don't successfully retry. more

Email in the World’s Languages - Part III

In our last instalments we discussed the various ways to encode non-ASCII character sets, of which UTF-8 is the winner, and some complex approaches that tried to make UTF-8 mail backward compatible with ASCII mail. After years of experiments, the perhaps surprising consensus is that if you're going to do international mail, you just do it. more

9 Thoughts on Stepping Up Spam and Malware Enforcement

In a tweet, EU commissioner for the Information Society Neelie Kroes congratulates OPTA on the spam fine for the golf ball printing company Backsound. Since 2004 the Dutch OPTA is the number one spam and malware fighter of the EU with a total of €1.9 million in fines. It made me ask two question to myself: How come that we seldom hear of other spam fines in the EU? And can the EU change this in any way? more

IDN Evolution Discussed at ICANN Cartagena

Internationalized domain names (IDNs) have been available to Internet users for many years, but this year the first fully non-Latin IDN domains have become enabled by ICANN and country-code top-level domain registries. The recent success of the launch of Russia's .?? (.rf) ccTLD shows that there is an enormous demand for domain names in Internet users' native languages. more

Canada’s Anti-spam Bill C-28 is the Law of the Land

It's been a long time coming, but Canada has an anti-spam law, and one, which sets a new world standard, and a tough, but fair, opt-in protocol for everyone in North America who sends commercial email and other electronic messages. Yesterday, The Canadian Senate voted to accept Bill C-28, and today, December 15, at 13:00 eastern, it will be given Royal Asset of the Governor General of Canada, His Excellency the Right Honourable David Johnston. more

The Spamhaus Whitelist

For several months I have been working with the Spamhaus project on a whitelist, which we announced to the public this week. While this is hardly the first mail whitelist, our goals are somewhat different from other whitelists. Think of e-mail as ranging from inky black to pearly white... more

Google Voice: Race to the Bottom for Telephony - or Something Else?

Just when you thought making phone calls couldn't get any cheaper, along comes last week's news from Google about their latest iteration of Google Voice. There have been several steps along the way for Google to get to this point, and there are a host of reasons why this news is of interest to service providers of all stripes. I often write about how certain technologies and disruptive forces change the business of being a service provider, and this is but the latest example. more

Are Portable Email Addresses Possible?

News reports say that the Israeli government is close to passing a law that requires portable e-mail addresses, similar to portable phone numbers. Number portability has been a success, making it much easier to switch from one provider to another, and address portability might ease switching among ISPs. But e-mail is not phone calls. Is it even possible? more

ISPs Are Speaking, Is Anyone Listening?

Lately I've been seeing and hearing a lot of quiet warning noises coming from ISPs and spam filtering companies about sender behaviour. I believe they're forecasting changes in how ISPs treat commercial email and what new issues senders are going to have to negotiate. The short version is that commercial mail is a mixed bag. more

Email’s Not Dead, Neither is Spam

Over the past few years, we have seen a plethora of over-hyped articles in the popular press and blogosphere crowing wrong-headedly about how 'email is dead'. Social networks like Facebook and Twitter, new and as-yet unproven technologies are the supposed death-knell for our old reliable friend, e-mail. I wrote about the rumours of email's death being exaggerated back in 2007 in response to such inanity. Since then, we've seen such a cornucopia of silliness of the 'Such & such is killing email' variety that Mark Brownlow compiled a bunch of articles, and their rebuttals at his excellent site... more

Warning, Danger Lurks Here: Exploring DKIM/ADSP Edge Cases - Missing message-id

This article is the first in an occasional series on DKIM/ADSP edge cases that may not be generally recognized or understood. Many people advocate DKIM/ADSP adoption without fully recognizing potential implementation and operational issues. The fact is that the email messaging environment is fraught with opportunities for poor outcomes because of common practices that need to be considered or poorly understood implementations that are not considered... more

Searching for Truth in DKIM: Part 1 of 5

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. more

Reply-All Creates a DDoS Attack?

One can read in an Associated Press article that the US State Department have their email system bogged down due to too many people use the Reply-All function in their email client. IT Departments have asked people to not use Reply-All and also threaten with disciplinary action. To me, that is the wrong path forward. more