Re: [v6ops] [dhcwg] IPv6-Only Preferred DHCPv4 option

[Tomek Mrugalski <[e-mail]>]

On 05.12.2019 04:48, Lorenzo Colitti wrote:
> Additionally, I would expect that a separate option would be simpler to implement on the server side. This is because the server can just continue to consider the lease time a property of the address pool, and treat this new option simply as a statically-configured option that is returned to clients iff they requested it in the PRL. If we use the same field for the lease timer and the V6ONLY_WAIT timer, then the server will need to change the lease timer in DHCPOFFER packets depending on whether the option was requested or not, and I would expect that to be more complex. +Tomek Mrugalski any thoughts on this?
>From the server perspective, a new option is much simpler. There's no question about it. Every DHCP server I know has the ability to define custom options, so deploying this should be a simple configuration change, no code change. Most servers offer reach policy mechanisms to govern sending options back that can be used to fine tune sending the option back (blacklist specific devices, list clients by MAC/client-id/whatever, do client classifications, etc.).

In the DHCP protocol, most burden of tracking various timers is on the client side. Server really needs to track lease expiration since there's no lease being assigned, there's no state to maintain here on the server side.(Ok, it's a bit of oversimplification.) This should scale really well.

Tomek