PMDF Obsolete Features
4.4 Addressing Solutions
As the SNADS world is effectively limited to eight character by eight
character addressing, while the RFC 822 world has arbitrarily long
usernames and domain names, the issue of address transformations must
be addressed, particularly how to represent RFC 822 addresses within
the SNADS world. There are four general approaches which can be used
with PMDF-XGS singly or in combination.
- PMDF can be (and generally is) configured to convert specified
short form host names into fully qualified domain names. Thus if an RFC
822 address uses no more than eight characters in the user name and no
more that eight characters in the host name part of the domain name,
then a natural setup is to simply represent the RFC 822 address on the
SNADS side in truncated form, with merely the user name and host name.
- PMDF can be configured to use pseudodomain aliases for specified
RFC 822 domain names, e.g., "comp" for
"complicated.subdivision.com". Or if long usernames are an
issue, PMDF can be configured to look up short aliases in a database or
databases to be transformed into actual long addresses.
- PMDF can be configured to "autoregister" addresses going
to SNADS. That is, when PMDF sees a "long" address going to
SNADS, PMDF can automatically generate a unique short form address,
substituting the generated short form in as the From: address on the
message going to SNADS, and looking that short form up and substituting
the true "long" address back in if a SNADS recipient replies
using that short form address. For more information, see Chapter 3 in
the PMDF System Manager's Guide.
- PMDF's addressing channel can be used as a way to let SNADS users
send to any arbitrary address reachable through PMDF. SNADS users can
send a message to, e.g., MAILMAN@PMDFnode, with the
actual long form RFC 822 recipient address embedded in the text of the
message and specially marked for PMDF's use, and PMDF will pull the
real address out of the message text and resend the message to that
specified address. See Section 27.1 in the PMDF System Manager's
Guide for details on the format for embedding such addressing
information in the text of the message.