CWI has had a long history dealing with internet related services, like e-mail. Going from being the european hub in the European UNIX Network, to the endsite it is now, we have seen a myriad of mail setups and configurations. Recently we revamped the backend of our e-mail infrastructure departing from an 'all on one server' philosophy and splitting several components into well defined building blocks, whilst only marginally modifying our primary outward facing mailserver.

By splitting services and layering all the extra checks one nowadays has to perform on any incoming e-mail message the right tools for the job can be selected, allowing for a better price/performance characteristic to be formed for the entire CWI mail environment.

The original CWI e-mail infrastructure was based on one primary machine accessable to users via NFS and POP3. Nowadays we offer Spam tagging, Virus blocking, DNS based blacklists, Mail Filtering & Sorting coupled with Webmail and IMAP access on a total of 6 servers. This whilst utilising a failover or resilience strategy at the incoming and storage focal points.

Henk Roose (on the right) and JP Velders work at the National Research Institute for Mathematics and Computer Science in the Netherlands (CWI) as Systems Administrators and Network Engineers. CWI performs frontier research in mathematics and computer science and transfers new knowledge in these fields to society in general and trade and industry in particular.

Henk and JP have been working at CWI for 5 years now. Henk has over 15 years experience in the I(CT) world, whilst JP has been studying Computer Science and Physics for some years next to his work at CWI and participates in several Open Source and Open Standards related communities.

The current mail setup was designed by both; JP, though, is the more vocal of the two.