eap Mailing List: Relationship between AAA-Key and MSK/EMSK

[Tschofenig Hannes (hannes.tschofenig]

hi all, 

this issue come up when we discussed (Yoshi, Alper, Jari) the relationship
between the AAA-key and the MSK/EMSK in PANA . 

it is said that the AAA-Key is derived from the MSK and EMSK. 

the eap-keying document does not specify how this key derivation is
achieved. 
worse, in Section 4.2.1 the text says: 

"  The AAA-Key is derived from the keying material exported by the EAP
   method (MSK and EMSK).  This derivation occurs on the AAA server.  In
   many existing protocols that use EAP, the AAA-Key and MSK are
   equivalent, but more complicated mechanisms are possible (see
   Appendix E for details).
"

appendix e, however, does not help since it talks only about a very special
case, namely fast handoff. 

we dicussed this issue in one of the eap keying design team phone
conferences but it got lost somehow. 

it would be more helpful to provide a proposal for AAA-Key to MSK/EMSK key
derivation. 

ciao
hannes