Mailing lists and DKIM

DKIM will benefit to internet users if most emails are signed using DKIM. Many of the emails everyone received are comming from LS (List Server), that's why we propose DDX group to experiment DKIM on LS. Experimentation would start with the specification for a  reasonnable implementation.  Naturally, Sympa LS software which is used by internet2 should be the LS used for this.

DKIM and MLM general issues

There are various questions about what a LS (list server) should do with DKIM signed messages. A simple answer "keep original message unchanged" may not be a sufficient answer for various reasons :

• One of the initial goal is to be able to check the message origin against white list, black list or reputation services. This requires message origin verification, that's why a signing technology is needed. In the LS case, the LS reputation could be checked, not only the original sender reputation.
• Most of existing LS modify some parts of the distributed messages and alter the original DKIM signature thereby. It is not the goal of the DKIM WG to specify what kind of message modification is unwanted or not. There is an agreement that we don't expect LS implementations to give away message customization ; they are related to features of interest for LS users.

The goal is to specify a clear way for a LS to implement DKIM and tell in which situations a List Server MAY/MUST/SHOULD remove an existing DKIM signature and add its own signature. ietf-dkim mailing list archive can help. Thre are a lot of discussion about LS, unfortunetly thre a poor number of conclusions.  One of the threads can introduce you to the question to solve. It's quite old (2006) but stll up to date. Stephen Farrell submitted an overview of the discussion that could be read first. A [[an overview of the discussion. Unfortunately this summary covers only half of the discussion, there were lots of comments after it was sent