Subject: Re: [44net] Tunnel mesh is (mostly) down From: "Michael E Fox - N6MEF" n6mef@mefox.org Date: 01/06/2015 12:32 AM
To: "'AMPRNet working group'" 44net@hamradio.ucsd.edu
Hmmm. Given a 1 hour timeout, then any error would need to be detected and corrected within that hour, or else routes will still be lost. Correct?
It would seem that a timeout of something more like 24 hours would be more practical.
The rationale behind the 1 hour timeout is not to cover errors and outages, although it could cover cases where e.g. the server has to be relocated within the same room, or network maintenance occurs.
The reason is that one of the hypotheses is that there is packet loss that drops the RIP packets, and when two subsequent RIP bursts would each loss the last (or n'th) packet e.g. because of a queue overflow somewhere the route would be already lost. The chance of this happening to 12 subsequent broadcasts (1 hour) is smaller.
Further increasing the timeout would mean that a route that is no longer present would take much longer to disappear, unless a mechanism as described by Marius is added. (where a deleted route is announced in a special way)
With that modification, the timeout could be safely set to something like 1 week.
Rob