Ahmad
I have a query
regarding the handling of Binding Revocation by MAG for individual binding
session.
Following is the
scenario:
Scenario:
1. Proxy Mobile
Initial Registration, MAG sends PBU to LMA with HNP option set to ALL_ZERO for
MN 1.
2. LMA in turn
sends back PBA with 3 HNP(s) assigned to MN 1 and updates Binding Cache
Entry.
3. MAG updates
Binding Update List entry and sends Router Advertisement to the MN with all
the
prefixes and prefix lifetime.
Note: MAG considers the prefix lifetime as binding lifetime and starts Binding
Lifetime timer.
4. Bi-directional
tunnel is established between MAG and LMA.
5. Prefix Route(s)
are created for all the prefixes at MAG.
6. MN 1 gets one
IP Address from the alloted 3 HNP(s).
7. LMA sends BRI
message with one HNP (out of the alloted 3 HNPs) with revoke trigger as
"ADMINISTRATIVE REASON".
After step 7, when
MAG receives BRI message with only one HNP and MN-ID:
Queries:
1. Will MAG stop
the binding lifetime timer (started after binding session establishment), due
to the
received BRI message?
2. Will MAG delete
the complete Binding Update List maintained for the MN (MN 1) or will it
delete
only the corresponding HNP entry from the BUL and send RA message to MN 1
(eventhough
the IP Address used by MN is not from the HNP received in BRI message)?
If it deletes only the
corresponding HNP entry, what will happen to the
Binding Lifetime timer?
[Ahmad]
If the LMA assigned 3 HNP
for MN1, then if the LMA would like to revoke all of the HNPs, the
LMA have one of the following
options:
1. Send BRI with MN-ID option
ONLY. This means that all HNPs are revoked, or
[Magesh] If there
are multiple interfaces (multi-homed) for the same MN, will MAG
remove the Binding Update List maintained for all the interfaces,
as there is no
Link Layer Identifier Option in the BRI
message?
2. Send a BRI with MN-ID and all
HNPs.
Although, the draft recommend
Number 1 BUT does not prevent No. 2.
On the other hand, if the LMA
sends a BRI with MN-ID and a single HNP, then the MAG MUST consider the
revocation of that single HNP and MUST NOT remove the MN1 from the
BUL.
[Magesh]
What will be the
status of binding lifetime timer?
Will the timer be
running even though the single HNP is removed from BUL entry (or will the
timer be stopped).
IMO, if LMA tries to
revoke a particular mobility session (Binding Cache Entry), it has to send the
MN-ID and all the
HNP(s) allocated for
the particular session. Sending of one HNP
out of
the allocated n HNP(s) should be
treated as Invalid
Case. The behavior should be same as PBU received from MAG for De-Registration
(where all the
HNP(s) allocated are
present in the PBU message).
Hope this
help.
Regards,
Ahmad
Thanks
S
Magesh
