User Access

[Kartic]

Hi,
I have created an application in vb.net using SQL Server 2000 database .
What I want is to restrict users to access the application more than
once,from the same computer or from any other computer. What is the best way
doing it as database is disconnected.

Currenty I am storing/flag the login name in some table at the time of
appliation load, and remove it when the user close the application. But it
doesn't work always, especially when program closes abnormally. To remove
the flag I have created another program. I still dont know what is the right
way doing it.
Any help/suggestion would be appriciated.

Thanks, Kartic

 

[William Ryan]

That's a formidable task b/c ADO.NET is architecturally
such that the user could pull the network cable out after
a query, do their thing for a few hours, plug the cable
back in and Update. You could check sysprocesses to see
if they are in the system, but even that is going to be
suspect.

If you are using SQL Server, you could run sp_who2 for
instance and verify a that they aren't already logged,
verify that the hostname of the machine they are on is the
same. You could then check that if they are in the
system, look at the CPU time they are using but even that
is pretty weak.

I think what you are doing now is probably more reliable
than most other methodology...perhaps you could write some
advanced code to try to capture most abnormal closes---but
that too would have some gaps. The more I think about
it..I can't think of a foolproof way to address this, but
hopefully someone else can.

Sorry,

Bill