Software to help us

Good day everyone



Can someone please tell me if there is a software package on the market that
will enable the Administrator of a Microsoft network to see what a client pc
is doing that causes the network to slow down significantly. If possible it
must send out an "alarm" if it detects misuse of the system



I don't want the Administrator to spy on the end users, but we have people
doing audio / video streaming, send / receive large mail attachments and so
on





Thanx in advanced