AC> FTS-9 specifically mentions a "serial number" with regards to MSGID
AC> generation, therefore two consecutive messages should contain MSGID
AC> serial numbers that follow each other in series, surely?

AC> (Is there anyone who would like to interpret the spec differently?)

To serialize something, in practical terms, doesn't necessary mean that
it must be in "series", "incremental in nature".

It could mean that it progressive or a chain,  "you serialize it so that
you can follow a chain of events".  Does serialization imply
reversibility and accountability?

How ever you want to intepret it, FTS-9 is just concern that the number
is unique on the originating system for a period of 3 years.

How do you achieve this is your goal in your design with the
consideration of all the parameters and issues you have to deal with,
namely, compatibility with other software not only running on the same
machine, but on others as well.

Surely, one can be an anal retentive semantic meaning and simplest use a
"serial counter" to result in the a basic progressive incremental
"counter" system.

Well, first, there is no guarantee this "counter" will be unique
across other systems.  But lets just concern ourselves with what
FTS-9 says "Unique on the original system" only.  That is what it
says. Right?

This presents a multiple of problems since in order to guarantee
uniqueness, all email generating processes in the system whether its
coming from a multi-node, multi-threaded system,  3rd party door system,
they all must have a "COMMON SERVER", if you will, to retrieve the last
number used.  Do you see the picture? Do you understand this problem?

So currently, most systems use their own implementation because there is
no standard mechanism for one to get the "current count" so that one can
increment it.

BTW, new Client/Server software do allow for this to happen now. Wildcat
5.0 requires that you use the SERVER to create or toss a message and it
will always return a unique message id for its own dupe checking system.
This is all relative to the installation. There is no way to retoss the
same message.  No way. Obviously, the vendor has factored in some
"parameters" of the message into the "equation".

In my opinion, this is ideal and is required. By using a serial number
counter, you have effectively removed or excluded the parameters of the
message itself and this increases the likelyhood that two SAME messages
can be theoritically tossed into the system.

Whatever the "equation" one uses, it must be a
"Function" of the message
parameters IMHO.

But regardless, whatever the "function" is, lets look at one of the
fallacies of FTS-9:

It says that no two messages can have the same serial number on the same
machine.  Well, that implys that the SAME TWO MESSAGES can not have the
same serial number on the ANOTHER MACHINE.  Right or Wrong?

If you say WRONG, you can stop right here. If you say right, then you do
grasp the situation and then further analyze, that it also says that the
generation of this unique serial number is "left to the implementor".

Well, unless two systems USE the same "implementation" there is no way
that one can guarantee that another implementation will NOT "REPRODUCE"
a serial number that was already another system and sent to your system.

So my point is, you can go directly to the specs and attempt to follow
it and you will see that many things, there are issues that doesn't
quick make sense.  Remember, it is not the bible.  The authors of the
specs make great contributions but they are also not great sages with
perfect vision into the future.  Many times, it just doesn't quite
work.  If it did, we would be having many of the debates in this echo.

You need to take the specs and do the best you can with them. If they
are issues or questions about usage, bring it up.

In my opinion, if there is one major problem with FIDONET mail formats,
is the LOST of addressing.  FTS-9, MSGID/REPLY offered an great
opportunity to maintain this addressing which HELPED alot of BBSes and
it certainly helped alot of users.

In this echo, we get LOST of "serial numbers" and the chaining of the
FTS-9 and it has hardly any impact in the fido market. Almost none
whatsoever. We throw away the important of addressing.
--- Platinum Xpress/386/Wildcat! v1.2j