randomizing lease renewal?

Scott Helms khelms at zcorum.com
Fri Mar 30 19:06:57 UTC 2007

> There is a big difference between dropping a link and readdressing an 
> endpoint.  The former may cause a minor interruption in traffic flow, 
> which may then resume if the outage is short enough/timers long 
> enough.  The latter is guaranteed to break all existing sessions, 
> requiring the user to reconnect, reauthenticate, etc.

For a momentary disruption this is true, but if a cable modem goes
offline the the retrain time in any real world system is far longer than
the time outs for common transfer protocols like HTTP and FTP.  The same
is true for most broadband access methods.  I work with hundreds of
ISP's around the country and its a truly educational experience to log
into a CMTS and run the flap list report.  

> > I think that OSS loses when we decide that a feature isn't "moral" 
> > to include since closed source vendors don't have the same 
> Well, it is OSS so anyone can include any feature they want.

Yep, and if I had the time I'd write a patch myself.  I don't so I end
up doing this kind of thing with scripting and in some cases with CNR.
Scott Helms
Vice President of Technology
ISP Alliance, Inc. DBA ZCorum
(678) 507-5000

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