Thanks for your response!

whats the protocol your application uses ? I mean as how exactly is done ?
is it done through FTP Protocol or through HTTP ?
*The application uses TCP/IP for communicaiton between backup server and
clients*
[moderator's note: TCP/IP is not a protocol, it's the an entire
technology. See http://en.wikipedia .org/wiki/ TCP/IP. The answer to
this question and the others requires me to add the performance
testing FAQ. Please see below.]

Remember most of the Load testing tools works with protocol rather than
technologies used.
whats your objectives here,is it possible to have more than one instance of
your agent per machine ?
*No...All clients will have a single agent installed. The objective is to
measure the time taken by backup server to backup data from*
*a) 5 clients*
*b) 50 clients*
*c) 500 clients and so on...*

SilkPerformer can be used for client server application but you need to
understand that efforts required will be more in case protocol is not
supporting completely or properly.
*I understand and am trying to find out if SilkPerfromer would support
testing for my scenario in some way.*
**
Thanks,
Vivek