Question : Nortel VPN Installed as a service or client ?

Can anyone tell me the differences between installing the Nortel VPN Client as a service as oppose to an application?  I am looking for a breakdown of pros/cons as to why it would be better to have it installed one way as oppose to another.  Enivironment would be a Windows XP Pro ( desktops) in an Active Directory domain. Remote users would require the ability to change AD passwords as well.

Answer : Nortel VPN Installed as a service or client ?

If installed as an application logging on and off will not work. As for doing so as a service I would recommend testing it, but I am doubtful it will work.
Some folks have been able to get some VPN clients to connect as a service, often using the Windows VPN and Microsoft utilities such as srvany and RAS dial, but the best way to achieve it is to create a site to site VPN between two VPN routers. This way the tunnel is always "up" and the remote network always available at logon.