Subject: Re: [mobile-ip] MIPv6 I-D 18: Miscellaneous Comments

From: Jari Arkko <[email-masked]>
Date: Wed, 07 Aug 2002 15:43:55 +0300

Vijay Devarapalli wrote:

> Kevin Miles wrote:
> 
>>So at any time the mobile can choose to switch from S=1 to S=0? Which begs the
>>question, can it also switch the other way and manage its set of BCEs
>>individually? (Isn't this where we came in :-)
>>
>>I can't actually think why it would be useful for a mobile node to want to
>>change the value of S in either direction during a single binding. Does anyone
>>have a reason for allowing this?
>>
>>My preferred resolution is to declare that the value of S on all rereg and dereg
>>BUs is ignored and treated as if it were the same as on the original BU. (If the
>>mobile node really needs to change the value of S, it can always dereg and reg
>>again.)
>>
> 
> I agree with Kevin.

Ok.

Suggested text. Add to fifth bullet of section 11.6.1:

   The value of the `S' bit MUST be set equivalently
   for subsequent de-registrations and re-registrations
   with the same addresses.

and then in 10.2:

    If the `S' bit field in the Binding Update is zero, The home agent
    creates or updates Binding Cache entries for each of possibly
    several home addresses.  The set of such home addresses is formed
    by replacing the routing prefix for the given home address with
    all other routing prefixes on the mobile node's home link that are
    supported by the home agent processing the Binding Update.  The home
    agent creates such a separate primary care-of address registration
    for each such home address.  Note that the same considerations for
    Duplicate Address Detection apply for each affected home address.

=>

    If the `S' bit field in the Binding Update is zero, The home agent
    creates Binding Cache entries for each of possibly
    several home addresses.  The set of such home addresses is formed
    by replacing the routing prefix for the given home address with
    all other routing prefixes on the mobile node's home link that are
    supported by the home agent processing the Binding Update.  The home
    agent creates such a separate primary care-of address registration
    for each such home address.  Note that the same considerations for
    Duplicate Address Detection apply for each affected home address.
    The value of the `S' bit field is examined only for new registrations.
    Its value is ignored on de-registrations and re-registrations
    of the same addresses.

Jari