>From 4.1 onwards there is Adaptive sub-file backup for Mobile Clients.
I don't use it or know much about it but I think it allows you to backup
the changed bytes/blocks of a file on a laptop rather than the whole
changed file.
This may be of some use to you depending on the data they are backing up.

Cheers
John



                    "Richard Sims"
                    <rbs AT BU DOT EDU>

                    Sent by:             To:     ADSM-L
                    "ADSM: Dist
                    Stor Manager"        cc:
                    <ADSM-L AT VM DOT MAR       Subject:     Re: Remote clients 
transferring GBs over WAN
                    IST.EDU>


                    26-Mar-2003
                    13:17
                    Please respond
                    to "ADSM: Dist
                    Stor Manager"
                    <ADSM-L AT VM DOT MAR
                    IST.EDU>





>The organization I work for has four main establishments. Typically,
someone
>will go "on mission" to another establishment and perform a backup of his
>laptop. Since his dsm.opt points to a server that that is hundreds, if
not,
>thousands of kilometers away, this backup will be done over the WAN and
not the
>usual LAN. Occasionally, this user might even attempt to backup 1 or 2 GBs
over
>the WAN. This obviously causes some problems.
>
>What to do about this? Blocking the port in the firewall comes to mind but
that
>is not a real answer.  Has anybody encountered this problem and what, if
>anything, did you do? Thank you...

Such backups have to be painful for the laptop user as well.  I should
think
that following the procedures outlined in the Windows client manual under
"Performing a backup with limited bandwidth" should yield relief.
There is a whitepaper on the IBM site describing it in fuller detail.

  Richard Sims, BU