randomizing lease renewal?

Chuck Anderson cra at WPI.EDU
Fri Mar 30 16:52:09 UTC 2007

On Fri, Mar 30, 2007 at 10:57:59AM -0400, Scott Helms wrote:
> In addition, the whole "it is really, really bad for 
> the internet." is based on assumptions of why people want this feature 
> and an exaggeration of what occurs when you do force a client to another IP address.  
> Most of the commercial DHCP servers support this function, certainly
> Cisco CNR does, and since CNR is used by many MSO's (including using
> this function) the idea that dynamically forcing the client to another
> address is terrible is pretty silly.  Its certainly no more disruptive
> than having a cable modem drop offline in mid-communication.  However,
> it is against the RFC, but IMO that is simply artifact of the prevalent
> opinion.  I have great respect for the authors of the ISC DHCP daemon
> and the community, but in this I greatly disagree with the stance they
> have taken and I believe its based far more on philosophy than fact. 

If a client starts downloading a large file that takes 8 hours to 
download, but they are forced to change their IP every 4 hours, then 
they will never be able to download the whole file.  Their client will 
keep retrying (restarting from the beginning if the client or the 
protocol doesn't support resume functionality) causing unnecessary 
load on the server.  This is pretty bad for the Internet.

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