A. M. Osborne,
S. Santiago IT/ASD,
B. Pollermann IT/DCI
For nearly 10 years, the Electronic Mail Address Directory database (emdir) has been used to store electronic mail addresses - both for people at CERN and for other geographical populations.
emdir started as a small demonstration project to show that the combination of two techniques quite new at the time - commercial Relational Databases and Remote Procedure Calls - could provide reliable, efficient and fully functional new services. All through its life emdir succeeded in implementing features which only later became of general use. Amongst these were a three-tier architecture (multi-platform client, dedicated application server and a universal back-end database server), shrink-wrapped, downloadable, multi-platform client installation packages, database update permissions based on automatic authentication of the client users, etc. emdir survived two radical changes of computing environment: it started on a central VAX/VMS with communications based on DECNET, was extended to run on VM/CMS with both DECNET and TCP/IP and was finally fully rewritten to run over TCP/IP on practically all the UNIX platforms at CERN and had a WWW interface added for read-only operation. At the time that these lines are written, emdir still receives a few hundred calls per day.
emdir was originally written by Frederic Hemmer, later modified by Claude Ledez, and fully rewritten by Jorge Dominguez-Sol. The RDBMS was ORACLE.
Due to the advent of the Web, the requirement to provide support to populations outside CERN no longer exists. Since 1987 the Computer Centre Database (CCDB) has been used to register users, their accounts and at the same time make entries into emdir. In order to consolidate the maintenance effort, emdir will shortly be absorbed into CCDB. The effect of this will be the following:
xwho(basically a line mode Web version)
phonewith the `-M' option
phonebwill be enhanced to provide similar functionality to that on UNIX.
Please note that any change made to e-mail addresses (either the generic address or the preferred e-mail address) are seen via the directory services only the next morning, since, for efficiency reasons, they are based on database snapshots. For the purpose of e-mail routing, however, snapshots are taken twice per day - once in the early morning and once at lunch-time.