Handover Keys Using AAA (draft-vidya-mipshop-handover-keys-aaa-03.txt) vidyan@qualcomm.com narayanan.venkitaraman@motorola.com gerardo.giaretta@telecomitalia.it hannes.tschofenig@siemens.com julien.bournelle@int-evry.fr

Changes since Dallas Two reviews received (official MOBDIR and unofficial SECDIR) and comments incorporated Summary of changes: Replay protection mechanism using timestamps alone Sequence number field removed; no need for both sequence number and timestamps Timestamp allows stateless AAA server function Error codes streamlined Fixed IANA section Defined PRF Message summary added for clarification MAC Option to be pulled into RFC4068bis Draft will be revised after update of 4068bis Technical work is mostly complete Extensive reviews received Appendices to be submitted as RADEXT and DIME documents Satisfied all criteria for adoption as WG document Adoption?

Backup Slides

Example Topology AP2.1 MN AP2.2 AR2 AAAH Server AP1.1 AR1 MN AP1.2

Protocol Overview AAA Server MN AR1 AR2 HKReq RADIUS Access Request HMK Generated HMK Generated HKReq ([MN ID, Msg ID, Seq #, MN Nonce], MN-AAA MAC) RADIUS Access Request ([HKReq, NAS IP], AR-AAA MAC) Validate MAC Generate HK1 RADIUS Access Accept ([AAA Nonce, Lifetime] AAA-MN MAC, [HK1], ARn-AAA Key) HKResp Decrypt HK1 Generate HK1 ([AAA Nonce, Lifetime] AAA-MN MAC) MN Handoff To AR2 FNA([FBU], HK1) [FBU], HK1 Validate FBU FBAck FBAck

Draft Goals Establish a handover key between MN and AR to secure FBU/FBAck Simple, single roundtrip protocol

Draft Status No current open issues Previous discussion – CoA validation prior to handover key derivation Discussion on how to update the draft and move forward

IP Address Validation Strictly in the context of FMIP Purpose – validate the CoA of the MN while deriving the handover key

IP Address Validation Mechanisms Controlled networks may have their own means of IP address validation On links such as PPP, IPv6CP can provide tight control over IP address assignment Some technologies would allow binding of L2 credentials to IP addresses at the time of network access Other more definitive methods also possible Consensus on providing guidance in the security considerations section