Subject: [mobile-ip] Comments on draft-team-mobileip-mipv6-sec-reqts-00.txt

From: Alexandru Petrescu <[email-masked]>
Date: 16 Aug 2001 14:24:56 +0200

Hi,

I have further comments on this draft that I believe have not yet been
mentioned.

-the table in section 6 has threat B.4 but it is not described
 anywhere in the body.
-I propose addition of a DoS attack realized by sending fake Binding
 Acknowledgments (this is also mentioned in
 draft-roe-mobileip-updateauth-00.txt):
   Threat B.5:

   By being able to passively monitor the traffic, the attacker could
   learn about the CNs that the MN is communicating with and also
   determine to which CNs the MN is sending BUs.  The attacker could
   thus synchronize with the MN such that when MN sends a BU to CN
   then attacker replies to MN with a fake Binding Acknowledgment with
   a Status field different than 0.

   Effect B.5:

   This will cause the MN to resend a new Binding Update (subject to
   rate limiting of sending BU's) to CN's.  Depending on timing and
   synchronization, this could result on a DoS or low-grade service:
   the communication between MN and CN can be shut off or it can
   follow an unoptimized triangular route.

   Requirement B.5:

   I don't know.  Probably the mentionned draft has a good idea in
   this respect.

-in section 5 Classification of Attackers, after reading the first
 three lines I'm tempted to understand "link" as a "subnet".  But
 then, a "link" between CN an HA tends to be interpreted more as a
 large portion of Internet, including CN's and HA' subnets.  Thus I
 propose a finer distinction, for example replace:

  "-  an attacker on the link between the CN and the HA

   -  an attacker on the link between the MN and the CN"

 with:

  "-  an attacker on the path between the CN and the HA (except CN's
      and HA's links)

   -  an attacker on the path link between the MN and the CN (except
      CN's and MN's links)"

Thank you for reading these comments,

Alex