X.400 products are conformance and interoperability tested

Most X.400 products claim to conform to some profile - ENV 41021, NIST Stable Agreements and so on and so forth.

This is IMHO worth considerably less than is apparent at the surface. Consider:

All that said, the conformance tests are probably one reason why the community of X.400 implementors pay considerably more attention to what the standards actually say than Internet mail implementors do; if you're told at the outset that you have to pass a conformance test at the end, you think in terms of passing the test when designing the system.

Most Internet mail products are interoperability tested; they're connected to the Internet, and get to send and receive some mail before they are shipped.

This is a considerably less stringent test, because:

  1. Most E-mail systems on the Internet are liberal in what they accept; they will accept lots of egregious standards violations in incoming mail and "attempt to do the best they can".
  2. Testing will almost always involve only a few out of the thousands of different E-mail systems out there. Most of these will not stress the limits of what's permitted by the standards, but for every limit, there are some that will.
  3. Lots of current E-mail systems break standards. That influences both the code shipped and the mindset of the developers; it cons them into believing that "standards are not important".
The last point is important. Some products, for example early releases of Microsoft's and Lotus' SMTP gateways, were incredibly badly designed, full of bugs and totally out of conformance with the standards. They seemed to have been written with a mindset of "slap something together that works part of the time; nobody cares about standards on the Internet anyway".
(The developers were justly flamed by the Internet community, and later releases have fixed a lot of the bugs; the attitude of the Internet community may be the Internet's only answer to conformance testing...)
Last modified: Tue Oct 8 08:51:03 1996