Subject: [mobile-ip] I-bit in Registration Revocation Draft

From: "Glenn Morrow" <[email-masked]>
Date: Fri, 25 Apr 2003 15:51:53 -0500

Steve,

Who exactly made the request for the I-bit?

> > Issue 2:
> >
> > While setting I=1 in the revocation message, the FA has to wait for 
> > the HA to ACK with I=1/0. Meanwhile the FA has to maintain the
> binding
> > and associated connections with the MN just incase the HA sets I=1 
> > in the ACK to notify the MN. When the HA issues revocation, it won't
> have
> > to wait for an ACK from the FA for clearing the binding, it can do 
> > that autonomously. This type of asymmetric behavior for the FA and 
> > HA does not fit into the philosophy of the revocation mechanism 
> > proposed and advocated in the draft; namely, the revocation 
> > mechanism is an
> FYI
> > scheme. Moreover, it is not clear from the current draft, what
> happens
> > when the FA does not get a response from the HA after
> retransmissions?
>
>      I don't think it fails to fit into the philosophy of the draft.
> The amount of state that an FA has to keep is very small; it's nothing
> more than the home address in a 'to-be-notified' list.  If HA(i=1)
> {notify}; remove(homeAddress).  If the answer doesn't come back, then
> the HA resorts to whatever it's default is, which the draft says SHOULD
> be to notify.
>
> [GM] Steve, the whole idea of this ID is to reduce the period of time
> state is needed to be kept by the agents. By adding the semantics of 
> one agent waiting on the other agent for approval of some sort 
> actually increases the state that the agents need to keep as well as 
> the time they need to keep the state.

     The 'I' bit was added due to 3GPP2 request.

---

From: "Steven M. Glass" <[email-masked]>
Date: Fri, 25 Apr 2003 18:02:22 -0400

> Who exactly made the request for the I-bit?

     That happened quite a while ago.  If it was made by email I most 
certainly still have it, if it was verbal e.g. at an IETF meeting then 
that information is lost to time.  The request was for a "selective 
inform" feature, and I did the translation into the protocol.  The 
reason was so as to not wake radios when it wasn't necessary, e.g. MN 
goes home, FA is told "revoke, don't signal" since there's nothing to 
inform.

                               Cheers,
                                   Steve