Subject: [nemo] issue 34 about Error in error processing, nemo base draft-02

From: Alexandru Petrescu <[email-masked]>
Date: Thu, 01 Apr 2004 14:35:36 +0200

S. Bellovin wrote:
> 5.4:    why is 140 not allowed in explicit mode? 6.6 implies that it 
> should be.

True.  My understanding is that the above remark comes from the
following two paragraphs in draft-02:

section 5.4
> If the Mobile Router sent a Binding Update to Home Agent in explict 
> mode then the Mobile Router interprets only the error status '141' 
> (Invalid Prefix) and '142' (Not Authorized for Prefix). For this 
> Binding Update, the Mobile Router MUST discard Binding 
> Acknowledgements with codes '140' and '143'.

section 6.6:
> If the Home Agent is configured not to support mobile routers, it 
> sets the status code in the Binding Acknowledgement to '140' (Mobile
>  Router Operation not permitted).

I think, in order to solve this issue, one possibility: modify the above
paragraph of section 6.6 to say that if this BAck corresponds to a BU
received in implicit mode then send 140 (Mobile Router operation not
permitted), otherwise send 141 (Invalid Prefix).

Second possibility, modify the paragraph cited of section 5.4 to say
that MR does interpret the 140 in the BAck in explicit mode too. And, if
MR receives BAck 140 after having sent BU explicit, then send a similar
explicit BU to another HA on the home link, and after all tried HA's and
still not BAck 0, then stop.

Alex