CERN Accelerating science

Introduction of a New Service: The Mail Server

Dietrich Wiegandt CN/DCI

When do you have to change your mail address? Certainly when you move house. But there are other circumstances that may require changing the mail address in a special way, e.g. when you are travelling a lot. In such a case you might want to keep your mail `poste restante' at some post office or you might find it convenient to ask for a post office box (POB) where your mail will be stored until you come and get it.

A similar possibility is now available for electronic mail with a very convenient extension: You can access your POB remotely without having to go to the post office to collect your mail, much like the way you can interrogate your phone answering machine at home from a hotel telephone.

The remote POB access is implemented via a client/server mechanism with the client program running on the computer you are currently logged into and communicating over the network with the server program on the mail server host.

The advantages of such a setup are:

• You can read your mail using any computer that
  • can reach the mail server host using a TCP/IP network connection and
  • has a mail user agent (MUA) program installed that knows how to talk to the mail server program, i.e. is an IMAP (Internet Message Access Protocol) client program.

• The mail address you specify on your business card does not change even if you are using many different computers for reading and composing your mail.

This service will soon be made available for UNIX users at CERN. Obviously, some prerequisites will have to be fulfilled before you can use the mail service.

• You have to get a post office box, i.e. you will have to be registered on the mail server. This is much like getting an account on any other central UNIX service or on a workgroup server host, however, some additional information is needed.

• Clearly some authentication is necessary to prevent unauthorized persons accessing your POB and read your mail. You will have to type your mail server password to be able to read your mail unless at registration time you have specified ``preferred mail reading hosts'' and you are currently using one of these machines to access your POB on the mail server. Note that you can have the list of ``preferred mail reading hosts'' modified later.

• The mechanism of the ``preferred mail address'' as implemented by the EMDIR scheme continues to function as before. Once you set your ``preferred mail address'' to point to the mail server POB, i.e. to

  userid@mail.cern.ch

  your outgoing mail will have the sender address modified to be a ``generic'' address, i.e. of the form

  Firstname.Familyname@cern.ch

  provided the mail program you are using has been setup correctly. At registration time the combination

  Firstname.Familyname

  will be checked for uniqueness at CERN and you may be asked for a modification, e.g. the addition of a middle name or a middle initial to avoid ambiguities. You can have the name part of your generic mail address changed later provided the result is again a combination which is unique at CERN.

• Once you are a mail server user, you should also make sure that a forward address pointing to your POB on the mail server is installed on all computers you have used before to read your mail, to avoid mail reception on those machines going unnoticed.

The recommended IMAP client mail user agent program for reading and composing your mail is ``pine ''. It is a public domain program available via ASIS on all CERN-supported UNIX platforms. It can be used on dumb terminals and in an X Window environment and can easily be configured to match the mail server requirements e.g. for the automatic generation of generic sender addresses. To help users of afsmail migrate to the mail server, a shell script will be provided to make the necessary configuration changes.

There are other IMAP client MUA programs in the public domain, but lack of manpower does not currently allow us to support any of these.

We hope to be able to officially start registering accounts on the mail service for UNIX users at CERN around the middle of November. By then the procedures for user registration should be in place and some last-minute configuration upgrades done. Watch the newsgroup cern.computing for the latest news.

Plans for including PC and Mac users are currently being discussed.

Enjoy your mail!