[98770] in North American Network Operators' Group
RE: question on algorithm for radius based accouting
daemon@ATHENA.MIT.EDU (Alex Rubenstein)
Fri Aug 17 00:52:49 2007
Date: Thu, 16 Aug 2007 23:52:34 -0400
From: "Alex Rubenstein" <alex@corp.nac.net>
To: "Joe Shen" <joe_hznm@yahoo.com.sg>, "NANGO" <nanog@merit.edu>
Errors-To: owner-nanog@merit.edu
> My question is: what's the best algorithm for
> constrcting broadband access record from radius
> accouting packets?
Read the RFC. No, I am being serious.
> Record Accouting-on packet arriving time ->
> record Accouting-Off packet's Acct-Session-Time
> and Acct-Delay-Time ->
>=20
> The Log-off time is calculated as:
>=20
> Accouting-on time + ( Acct-Session-Time -
> Acct_delay-Time)
Or, take the acct record from logoff, and:
(time stop acct record rec'd) - (acct-delay-time)
Either will work. However, it's somewhat more common to do what I
suggest.
> Log-on time is calculated as:
>=20
> Accouting-off arriving time - ( Acct-Session-Time -
> Acct_delay-Time)
Yes.
>=20
>=20
> Are the two methods have the same effect on
> calculating result? If radius packets were sent to
> two accouting systems simulataneusly, while the two
> system takes the different algorithm, will there be
> any difference between the result of accouting ?
They should yield (approximately) the same result. But, to be pedantic,
you haven't accounted for latency within the network.
