rfc 3473 notify security

["Hannes Tschofenig" <hannestschofenig@hotmail.com>]

hi all,

at the last ietf meeting allison mankin pointed to rfc 3473 as being 
relevant for the nsis working group (from a protocol and security point of 
view). reading the security section i noticed that the notify message is 
sent in a non hop-by-hop fashion and therefore cannot be secured using the 
rsvp available security mechanisms (i.e. integrity object).

the usage of ipsec is suggested for protection. working on the "rsvp 
security properties" document i realized that ipsec protection for rsvp is 
not a simple task (due to a number of rsvp protocol characteristics).

if the notify message is sent using raw ip (protocol type 46) then it is not 
possible to secure the message appropriately since ike, ikev2 or kink are 
able to negotiate this type of traffic selector.

possible solution:

a) disable the non hop-by-hop transmission of the notify message
b) use udp encapsulation (although depricated)

considering the additional overhead of securing the notify message it seems 
to be much easier to consider (a) as a viable option.

(b) would allow the source/destination udp ports to be used as a traffic 
selector (in addition to the src/dst ip address).

further thoughs?

ciao
hannes

_________________________________________________________________
Messenger  -  Wer in Echtzeit kommunizieren will, lädt den MSN Messenger. 
Cool, kostenlos und mit 3D Emoticons:  http://messenger.msn.de