The anti-spam organisation set up by Yahoo, Microsoft, AOL and Earthlink has released recommendations for tackling unsolicited e-mail - but none stretch beyond what is already commonsense.
The Anti-Spam Technical Alliance's (ASTA) Statement of Intent includes a list of suggestions and "best practice" recommendations for ISPs, e-mail service providers, governments, corporations and bulk e-mail senders.
Among other things, ASTA recommended ISPs shut down so-called "open relays" - e-mail servers that allow parties that do not own the mail server to relay mail through them without needing to log in first. The group also suggested ISPs crack down on virus and worm-infected computers on their network and closely monitor features that let people automatically register for ISP accounts.
If implemented, and with the backing of ASTA member companies, the recommendations could greatly reduce the amount of spam e-mail, the group claimed. The recommendations are the product of more than a year of collaboration between representatives of the member companies and focus, mainly, on ISPs, whose networks are often used to distribute spam.
ISPs that host Web pages should also remove simple programs that can generate e-mail messages, like formmail.pl, a popular and free program for providing feedback from a Web page. ISP customers should also be required to authenticate before sending e-mail from the ISP's network, ASTA said.
For bulk e-mail senders, the group discouraged the practice of harvesting e-mail addresses without the consent of the e-mail sender, as well as other common spamming practices such as source address spoofing and sending e-mail containing information that is false or misleading.
Consumers were generally let off the hook by the group. While e-mail users have a duty to educate themselves about spam, ISPs and others with a stake in e-mail need to do a better job providing consumers with tools and information to stop spam, the group said.
Many of the technical suggestions have for long been accepted wisdom within the technical community, said John Levine, a member of the Internet Research Task Force's Anti-Spam Research Group. "This is all kind of motherhood and apple pie," said Levine, who noted that AOL and most other ISPs have been following many of the stated best practices for years.
Despite that, the recommendations are still worthwhile if they can reform the small population of organisations with sloppy mailing practices, whose systems are frequently exploited by spammers, he said. "It's too bad that the first thing you have to do is tell people not to do something stupid, but there are still a lot of small companies with mailing lists and loosely administered mail servers," he said.
ASTA acknowledged that its anti-spam measures have already been adopted by most "responsible organisations", but stated that group members hope to encourage broader global adoption of secure e-mail practices and reduce the number of opportunities for spammers.
While not exciting, commonsense recommendations like those laid out by ASTA are a welcome relief to the Internet community, Levine said. "Generally the recommendations are reasonable. It demonstrates that the technical management of ISPs do understand the e-mail situation well."
Recommendations that are in line with best practices are more likely to find acceptance than novel new schemes or standards intended to stop spam, he said. "There was always some concern that ASTA was going to come up with something weird. The fact that you can look at this and say 'Yeah. Sure,' is good because it means that they're not going off on some tangent," he said.
Plans to stop spam have taken on a new urgency in the last year, as the volume of spam has increased and begun to eclipse legitimate e-mail traffic. In recent months, leading companies including Microsoft and Yahoo have proposed competing plans for e-mail sender authentication, which allows e-mail recipients to verify the source of an incoming message and stop spam e-mail messages that display forged or "spoofed" sender addresses.
In May, Microsoft agreed to merge its recently announced Caller ID anti-spam proposal with another, called Sender Policy Framework, or SPF. The company reached an agreement with SPF's author, Meng Weng Wong, to roll the two proposals into one specification.
Under the merged proposal, organisations that send e-mail will publish the addresses of their outgoing e-mail servers in DNS using XML. Companies will be able to check for spoofing at the envelope level, as proposed by SPF, and in the message body, as proposed by Microsoft.
A separate plan backed by Yahoo, called DomainKeys, uses public/private encryption keys to create a unique signature based on the content and origin of each e-mail message.
The ASTA document does not back either authentication scheme, but says both are promising and can be used to prevent address spoofing.
Behind the scenes, the document masks a heated battle within the IETF's MARID (Mail Transfer Agent Authorization Records in DNS) over the scope and details of the e-mail authentication proposals, Levine said.
However, despite disagreements within the group, those involved consider spam an urgent problem and plan to have a sender authentication plan ready for public viewing by the end of August. "I can't ever think of situation where there's been a feeling of urgency like there is with this. There's really a feeling that if we don't do something soon, people will give up on e-mail," Levine said.