Re: [dhcwg] WGLC: draft-ietf-dhc-dhcpv6-stateful-issues-00

["Hemant Singh (shemant)" <[e-mail]>]

Ted/Bernie/Ole,

Humble apologies I was buried with other priorities and did not check my DHC WG email folder in a while. I actually replied to the xlat document in v6ops during my 10 days of PTO up till the Labor Day.  Bernie kindly reminded me this week of this document.  Most of my comments have been addressed.  Some pending are included below.

Why was the CONFIRM message deliberately specified by RFC 3633 as not supported for the IA_PD?  

It would be good to reply to this question.  Otherwise the IESG is likely to ask the same question and the answer to such a question may uncover issues for us.  

For one, it is easy for a server to respond to a CONFIRM to an IA_MA by just matching the IPv6 address configured on the machine the server is running on.  I am always reminded by some authors of RFC 3315 that the server distinctly does not consult its client bindings to respond to a CONFIRM for an IA_NA.  The server just relies on the machine IPv6 configuration to compute a status of on-link or not-on-link.  Thus why it is not a sea-change to support the CONFIRM for the IA_PD option and we may need to step gingerly?  If the server has to respond to a CONFIRM for an IA_PD, the server now consults with its bindings (I think Bernie alluded to in his reply to this thread) which the server did not do before for the IA_NA.  Searching thru bindings has delay implications and additional server computations.  Or as I had already said in my earlier reply that the server checks what prefixes are configured on the server to determine on-link status.  However checking prefixes for IA_PD at a server has to exclude prefixes that are used for allocation of IA_NA.  So now the server maintains two types of prefixes.  

Thus I will try and propose some text over the weekend that IA_PD support in CONFIRM can't suffice with network configuration.  Some other data in the server needs checking and we should try and be little specific about the data.  Just saying something like "the sever checks network configuration" doesn't cut it for the IA_PD.  

Let me see what I can do over this weekend and propose some text as to how the server checks for on-link or not for the IA_PD to respond to a CONFIRM.  I will also catch up with other emails on this document and reply, if necessary.

Regards,

Hemant

-----Original Message-----
From: Ted Lemon [mailto:[e-mail]] 
Sent: Friday, September 07, 2012 12:22 PM
To: Bernie Volz (volz)
Cc: dhc WG; Wes Beebee (wbeebee); Hemant Singh (shemant); Ole Troan (otroan)
Subject: Re: WGLC: draft-ietf-dhc-dhcpv6-stateful-issues-00

Was that a yes or a no?