RFC 1082 (rfc1082) - Page 2 of 11

Post Office Protocol: Version 3: Extended service offerings

RFC 1082                 POP3 Extended Service             November 1988


       o Typically, each subscription address is not a person's private
       maildrop, but a system-wide maildrop, which can be accessed
       by more than one user.  This has several advantages:
             - Only a single copy of each message need traverse the
               net for a given site (which may contain several local
               hosts).  This conserves bandwidth and cycles.
             - Only a single copy of each message need reside on each
               subscribing host.  This conserves disk space.
             - The private maildrop for each user is not cluttered
               with discussion group mail.

   Despite this optimization of resources, further economy can be
   achieved at sites with more than one host.  Typically, sites with
   more than one host either:

        1.  Replicate discussion group mail on each host.  This
        results in literally gigabytes of disk space committed to
        unnecessarily store redundant information.

        2.  Keep discussion group mail on one host and give all users a
        login on that host (in addition to any other logins they may
        have).  This is usually a gross inconvenience for users who
        work on other hosts, or a burden to users who are forced to
        work on that host.

   As discussed in [RFC 1081], the problem of giving workstations dynamic
   access to mail from a mailbox server has been explored in great
   detail (originally there was [RFC 918], this prompted the author to
   write [RFC 1081], independently of this [RFC 918] was upgraded to
   [RFC 937]).  A natural solution to the problem outlined above is to
   keep discussion group mail on a mailbox server at each site and
   permit different hosts at that site to employ the POP3 to access
   discussion group mail.  If implemented properly, this avoids the
   problems of both strategies outlined above.

        ASIDE:     It might be noted that a good distributed filesystem
                   could also solve this problem.  Sadly, "good"
                   distributed filesystems, which do not suffer
                   unacceptable response time for interactive use, are
                   few and far between these days!

   Given this motivation, now let's consider discussion groups, both in
   general and from the point of view of a user agent.  Following this,
   extensions to the POP3 defined in [RFC 1081] are presented.  Finally,
   some additional policy details are discussed along with some initial
   experiences.





Rose