Re: Session Timeout

Michael Miller ( )
Tue, 06 May 1997 19:11:30 -0400

Josh Hillman wrote:
> > I tried to configure a Session-Timeout to prevent people from sitting on
> a
> > connection. I set it up for 10 hours, or 36000 seconds. Although the
> > setting is saved properly in the database, RADIUS returns a negative
> number
> > to the terminal server. Obviously, the user is logged out immediately.
> > What's happening here, Dale?
> What kind of NAS are you using? If you're using an Ascend Max, the
> attribute is "Ascend-Maximum-Time" and I've found a limitation with it (at
> least with my setup). I'm using software version 5.0Ai4 in the Max and
> currently, the Ascend-Maximum-Time can not be set higher than 32767 seconds
> (9 hours, 6 minutes, 7 seconds). Using 32768 or higher causes a dialup
> user to be disconnected (reason: session timeout) immediately after being
> authenticated.
> Ascend says it's a problem with RadiusNT because they can't duplicate the
> problem with their radius (unix-based). Dale says it's a problem with the
> Max but I forgot the reasoning behind it.
> Josh Hillman
> ----------------------------------------------------------
> Emerald Mailing List

Sounds to me like a problem with limitations of data type 'integer'. In
programming an integer is 16 bits long ( 2 bytes ). In theroy a data
range of 0 - 65535, however the most significant bit of the integer is
used for determining positive or negative status of the number, thus
resulting in a range of -32767 through 32768. What happens is when a
value of 32769 or greater is assigned, the most significant bit is set
to "1", however doing so to a data type of integer actually makes the
number negative instead of positive!!! The only way around this is if
there is a way of using a data type of longint to achieve a greater
range, which requires some code change in Radius (definatelly nothing
within our control). Unless in one of the next releases of Radius a
different data type is used, we are simply limited to a bit over 9
hours. Even if the data type is changed in Radius, I have no clue if
the MAX will even accept such a data type for the value anyways.

-- =========================================================="These days the search for detachment ans solitudeLead to retreating to fortresses no one would dare intrudeThere are those whose restless burdens start to showAnd then there are those, who unmistakeably must know."==========================================================God Bless,  /: /:        /:       /: /:           / :/ :ICHAEL /-:NDREW / :/ :ILLER==========================================================