[ILUG] [Possibly OT] Network Traffic Analysis and Interface Control

[Brian Foster]

On Wed, 22 Feb 2006, Hamilton, David (TSG C&I) wrote:
 > No. It's more a case of having to use an unreliable, high-cost
 > transmission medium which gives a highly variable bandwidth.
 > When the effective bandwidth does drop below useable levels, we have
 > usually found tons of TCP re-transmissions, and would therefore like to
 > use these as a criterion for shutting down the line due to lack of
 > financial viability of the session.

an off-the-wall idea:  diald(8)?
I know it's intended for PPP and dial-ups,
but it occurs to me it has two facilities
which are close to what you want:

1st, the actions it takes are controlled
by the contents of the packets.  so, at
least in theory, it can be configured to
"do something" on re-transmissions.

2nd, even if the PPP/dial-up/"do something"
is, on the face of it, an issue, it might
not be a problem.  it is possible to have
`diald' report things to a FIFO, and I do
know ('cuz I did it once) it is possible to
have a helper script read that FIFO and
then "do what is really wanted". see, IIRC,
diald-monitor(5).

I've no idea if something like this could
help, but it might be worth a quick look?

cheers!
	-blf-

p.s.  diald(8) plus wvdial(1) is an excellent
     means of controlling an out-going dial-up;
     I've been using them for years with almost
     no problems.
-- 
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