Subject: [mobile-ip] closing issue 50 (lifetimes)

From: Jari Arkko <[email-masked]>
Date: Fri, 28 Jun 2002 00:53:05 +0300

Issue 50 has been split from issue #50 as the single remaining
controversial item. Hesham's original complaint dealt with the
lack of justification for the 5 minutes of lifetime for the RR-based
BCEs.

A discussion followed, different types of attacks were discussed
and no real consensus or deep results were uncovered.

But I'd like to note a few facts regardless:

- The longer we make the lifetime, the longer an attacker
   can keep a binding that he created when he visited a
   network and forwarded the traffic of some node in the network
   to himself at another location (e.g. a home server).

- On a bombing attack, the actual bombing effect comes right
   after you establish the binding. Since an attacker can forge
   TCP ACKs or similar, he will be able to keep the bombing
   on for as long as the BCE is alive.

- We do not have a good quantitative model to describe the
   effects of the specific times to the seriousness of attacks.
   That is, even if we know that a change in the times
   changes the effects of attacks to some direction, we do not
   know exactly by how much.

- Creating such a model is not likely to happen in the next
   few days.

With the above things in mind, I'd like to suggest that we
accept that we have only partial information available, pick
a number that does not seem too troublesome from the security
point of view but allows comfortable binding lengths, and
use this number.

The current lifetime in the spec is 5 mins. I'd like to suggest
7 mins in Draft 18.

Jari

---

From: "Hesham Soliman (EAB)" <[email-masked]>
Date: Fri, 28 Jun 2002 14:57:51 +0200

> -----Original Message-----
  > From: Jari Arkko [mailto:[email-masked]]
  > Sent: Thursday, June 27, 2002 11:53 PM
  > To: [email-masked]'
  > Subject: [mobile-ip] closing issue 50 (lifetimes)
  > 
  > 

=> OK :) 

Hesham