Synchronized browsing

Christopher R. Hertel crh at
Mon Jan 1 20:00:34 GMT 2001

Alex Vandenham raised a question that I find interesting.  Here, if I 
have it right, is the scenario:

            |               |
        [LMB: FOO]       [Router]
  Lan2                      |
        |           |
    [LMB: FOO]  [LMB: URQ]

That is, Lan1 has a workgroup named FOO.  Lan2 also has a workgroup named 
FOO as well as a workgroup named URQ.

Now add a Domain Master Browser and a WINS server to the above.  They can
go anywhere.  It doesn't matter where they reside.  The DMB is for 
ntdomain FOO, thus promoting both FOO workgroups to the status of a 
single ntdomain.

 |----------+---------------+--|       [DMB:FOO]
            |               |              |
        [LMB:FOO]        [Router]---+------+--|
  Lan2                      |       |
 |------+-----------+-------+--|  [WINS]
        |           |
    [LMB:FOO]   [LMB:URQ]

Here's what happens:

On Lan2, LMB:FOO knows about workgroup URQ, and lists the existance of 
workgroup URQ in its browse list.  It eventually forwards that list to 
DMB:FOO.  DMB:FOO, in turn, eventually forwards the combinded list to the 
*other* LMB:FOO on Lan1.

So, Lan1's LMB:FOO now knows about workgroup URQ.

Unfortunately, since WINS does not register #1D names, there is no way 
for a client on Lan1 to *find* LMB:URQ, even though it knows about LMB:URQ.
Indeed, the Get Backup List Request for a workgroup is sent to the 
broadcast address on the apparent assumption that only the local 
<workgroup>#1D system will respond.

If a client on Lan1 could find LMB:URQ, it could send a unicast message to
get the backup list, but that's simply not how it works.  My guess is that
the idea of combining workgroups and ntdomains was not considered a good
one when this was all being designed. 

I would love to see some traces of this stuff.  I'm curious to know if the
client on Lan1 would try sending the query on to a DMB if it could not
find the LMB for the missing workgroup.  My guess is that no DMB is ever

I hope, Alex, that I have done a good job of describing the problem.  Let 
me know if I'm close.

Chris -)-----

Christopher R. Hertel -)-----                   University of Minnesota
crh at              Networking and Telecommunications Services

    Ideals are like stars; you will not succeed in touching them
    with your choose them as your guides, and following
    them you will reach your destiny.  --Carl Schultz

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