Re: [dhcwg] Reg RFC6704 (Forcerenew Nonce Authentication)

["Gaurav Halwasia (ghalwasi)" <[e-mail]>]

Hi Ted,

Thanks for your comments.

I am talking about a deployment where we do create *session* database for hosts either based upon DHCP packet (Discover) or the normal IP packet in case few of the hosts has not done DHCP but instead has just DONE DHCP INFORM to get the config parameters. So in this kind of deployment we do anyways maintain the session(or binding in terms of DHCP) database on the box. Having said that I don't think storing client information is a problem (at least in this deployment). The only extra thing which we would need to store is a 'nonce'. 
So I think it will be really useful to have nonce in INFORM-ACK callflow as it will also help in the usability of Forcerenew as per 6704.

Thanks,
Gaurav 

-----Original Message-----
From: Ted Lemon [mailto:[e-mail]] 
Sent: Wednesday, September 12, 2012 2:09 AM
To: <[e-mail]>
Cc: Gaurav Halwasia (ghalwasi); [e-mail]
Subject: Re: [dhcwg] Reg RFC6704 (Forcerenew Nonce Authentication)

I didn't say that FORCERENEW for DHCPINFORM clients was hard.   I said it would impact performance.   We would go from DHCPINFORM being a lightweight read-only operation to a heavyweight read/write operation.   I guess we could forgo the sync-before-ack logic of stateful DHCP, but this would add a lot of complexity to a performance-critical code section.

So yeah, from an implementation point of view, I don't really like this idea.   It seems trivial until you think about the impact it has either on performance or on implementation complexity.   If there's strong demand for it with a clear use case, then I think that's fine.    I wasn't able to tease one out of your rather dense message-could you try to state your use case in a short paragraph or two?