Subject: [mobile-ip] Controdiction between F_BACK and use of new CoA

From: Jing Caoyu <[email-masked]>
Date: Wed, 24 Apr 2002 17:31:12 +0800

Hi,
 
I am implementing fast handover draft draft-ietf-mobileip-fast-mipv6-04.
 
(1) On page 15, it says that "Upon receipt of the F-BU, the oAR must send a
F-BACK message to MN at its nCoA on nAR"
 
(2) In the next next paragraph, it says that "On the MN, the MN MUST  NOT
use the nCoA address as a source address until it receiveds a F-BACK from
the oAR."
 
Assuming the case in which MN didn't receive F-BACK in the old network, then
it has to receive the copy of F-BACK  forwarded to nCoA at the new network.
However, before the MN recieves the F-BACK, it cannot use nCoA as its source
address, as a result F-BACK with destination (nCoA) can't reach the MN at
ALL. As a result, the MN will never receive a F-BACK.
 
Is there a controdiction between (1) and (2)? Please reply to my message as
I need the information urgently for the implementation I am currently doing.
 
Thank you  very much!

Best regards,
 
Caoyu Jing
National University of Singapore