Re: [MEXT] draft-arkko-mext-rfc3775-altcoa-check-00.txt

Hi,

Romain KUNTZ wrote:
> Hello,
> 
> I think the current MCoA draft (http://tools.ietf.org/html/draft-ietf-monami6-multiplecoa-05 
> ) allows (or at least does not prevent) the use of the alternate-coa  
> option e.g. to register a CoA from one interface with a BU sent from  
> another interface.
> 
> Section 6.3
> 
>        *  If C flag is not set and an alternate care-of address is
>           present, the care-of address is taken from the Alternate
>           Care-of address mobility option.

==> The MCoA draft uses the C flag to indicate whether it is a
BU message for a bulk or single registration. If the C flag is not set
the BU is a single registration and the CoA must be taken from the Alt.
CoA option. In this case I think it must be the same as the source
address of the BU message (MN has only one CoA). If the C flag is set,
CoAs for each binding are taken from the BID options. In the bulk case I
think that the Alt. CoA option is omitted altogether. At least the MCoA
draft says that "...The alternate care-of address option MUST be omitted
when ESP is used to protect a binding update." (Section 5.4 Binding Bulk
Registration). If for some reason the MN doesn't use ESP and adds Alt.
CoA option I think that it must have same CoA as source address and in
Alt. CoA option.

So therefore I don't think that the new Alt. CoA check draft intervenes
with the MCoA draft...

BR,

Heikki

_______________________________________________
MEXT mailing list
MEXT@ietf.org
http://www.ietf.org/mailman/listinfo/mext