1. MIP6 RADIUS IETF-72 Update draft-ietf-mip6-radius-05.txt A. LiorBridgewater Systems K. ChowdhuryStarent Networks H. Tschofenig Nokia Siemens Networks

2. Overview MIP6-bootstrapping for the Integrated Scenario –draft-ietf-mip6-bootstrapping-integrated-dhc-06 –Aligns with Diameter Mobile IPv6: Support for Network Access Server to Diameter Server Interaction draft-ietf-dime-mip6-integrated-09 Since last updated added: Mobile IPv6 bootstrapping in split scenario –draft-ietf-mip6-bootstrapping-split-07 –Aligns with Diameter Mobile IPv6: Support for Home Agent to Diameter Server Interaction draft-ietf-dime-mip6-split-10

3. Next steps Resolve EDITOR’s notes Align the attributes with the DIME drafts –Final check as the other documents are close to being published. Make sure goals from: AAA Goals for Mobile IPv6 (draft-ietf-mext-aaa-ha-goals-01) are covered. –See next slide Write security consideration section Update Diameter compatibility section. Working Group last call post IETF-72?.

4. Issue with IKEv2 and PSK As per “AAA Goals for Mobile IPv6”: G2.12 The HA MUST be able to authenticate the MN through the AAAH in case a pre-shared key is used in IKEv2 for user authentication. – We don’t support that (nor does DIME-SPLIT). When IKEv2 is used with PSK-based initiator authentication, the pre-shared secret is carried inside the MIP-MN-HA-MSA AVP This is a mistake, since the AAA is not authenticating the MN and also the PSK should NOT be sent raw but instead the PSK should be digested as per 4306: AUTH = prf(prf(Shared Secret,"Key Pad for IKEv2"), )

5. Possible Solution To comply to the above, –Along with the AUTH data, the HA needs to send the IKEv2 msg, the Nr, the value prf(SK_pi,IDi') and the negotiated PRF function to the AAA. –The AAA can now compute its own version of the AUTH and compare it to that received from the HA – as per 4306 section 2.15) –If successfully authenticated, the AAA returns the prf(PSK,”Key Pad for IKEv2”) so that the HA can compute its own AUTH when it sends a response. Issues: –The AAA and HA have use the same PRF function. How does the HA know what PRF function is supported by the AAA? –For RADIUS we need to come up with a way to carry the IKEv2 message, the Nr, and the value prf(SK_pi,IDi') Attributes are limited to 253 octets and packet is limited to 4k octets.