Re: [dhcwg] Ben Campbell's Discuss on draft-ietf-dhc-relay-port-08: (with DISCUSS and COMMENT)

[Ben Campbell <[e-mail]>]

> On Nov 29, 2017, at 6:10 PM, Naiming Shen (naiming) <[e-mail]> wrote:
> 
> 
> Hi Ben,
> 
> Thanks for the review.
> 
> I agree with Ted’s comment on this. This is targeted mainly in a single admin domain.
> If an operator wants to turn on this feature on a relay(s), he/she can find out if the
> server or upstream relay supports this or not, and it’s easy to disable this feature
> if it does not work (could also be bugs in software).

Please see my comments to Ted (which crossed in the mail with your message)

> 
> Also, the configuration of the feature is on the relay, the upstream relays and
> server as long as has the software upgraded, they don’t need configuration. This
> is similar to other DHCP relay options, for example, the ‘Agent Cirucit ID’ or
> the ’Subscriber-ID” sub-option, which does not require relay do discovery to find
> out if server supports that or not, and as soon as the server has the updated software,
> it would automatically supports this.

Sure, but “as long as the the software has been upgraded” is an important precondition.

> 
> For the other "UPDATES..” tag. I’m quoting Bernie’s comment in another thread:
> 
> 	"We’ve already had this discussion and debate. It only UPDATES if you want to
> 	use this new capabilities, we don’t have a flag for that. UPDATES usually implies
> 	that you must do that.”

I don’t agree with that characterization of UPDATES. An update that adds an optional feature is still an update. Whether or not implementations are required to support it depends on the specifics of the update. The main purpose is that readers of the original RFC know they need to pay attention to the new one.

> 
> 
> Best Regards,
> - Naiming
> 
>> On Nov 29, 2017, at 1:19 PM, Ted Lemon <[e-mail]> wrote:
>> 
>> Ben, the idea is that this is a very targeted approach for SDNs, not something that makes sense as a general update to the DHCP base specifications.   Since relays and servers are generally within the same administrative domain, there is little danger of actual interop issues—the operator is going to be customizing these settings very deliberately.   We also tend to assume that the DHCP server is pretty easy to update compared to relays or clients, so the fact that an updated relay might not work with a non-updated server isn't a major issue.   This isn't like TLS 1.3 where the server and the middleboxes are operated by agencies unknown to each other.
>> 
>