Dialup Issues

A couple of questions relating to dial-up issues:

Is it possible to log who causes a dialup connection to be established for web access, i.e. the username or ip address ?

Secondly, is it possible to disable a user from having internet access and only email from the e-smith server. I imagine it could be done at a PC level by not configuring the PC to have the e-smith server as its default gateway - but what about disabling it at user level - which would be necessary if the PC is shared?

Thanks in advance.

Tim H