You have to enable time banking in the RadiusNT administrator first.
If the timeleft field is not null, RadiusNT will take the lesser of
that field and the Session-Timeout field, if a session-timeout
field is present.
If you are using Ascends, you need to check the Ascend Maximum time
option in the
RadiusNT administrator as well.
Currently, the option doesn't work correctly if you have both Ascend and
non-Ascend equipmen, since Ascend uses the Ascend-Maximum-Time
where as everyone else uses the Sesion-Timeout field.
We will be added some options to RadiusNT to handle multiple NAS type in