acct-delay-time appears to be off

[Alan DeKok]

Steven Staples wrote:
> I have been looking at this, and scratching my head.
> 
> It appears as if the (timestamp -(minus) acct-delay-time) does not always =
> the actual start time of the session.   From my observation, and log reading
> script, I have found that there could be a +/- 1 second variance in either
> the timestamp, or the acct-delay-times.  

  RADIUS accounting is to the second.  It doesn't include microseconds.

> Is there a way to use the microseconds to ensure that these values are
> accurate all the time?

  No.

> Is there possibly a better way to create a unique key, rather than what I am
> currently using as a unique group of fields:  
> Framed-ip-address + nas-ip-address + user-name + acct-session-id +
> ((timestamp - acct-delay-time) - acct-session-time)

  Don't use session time or delay time.

  If your NAS doesn't send NAS-Port or NAS-Port-Id, then it's difficult
to create a unique key.  The Acct-Session-Id attribute *should* be
unique, but many NASes are horrible, and re-use it.

  Alan Dekok.