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PANA Protocol Update and Open Issues. IETF 60. Since IETF 59…. Expert reviews by: Erik Nordmark, Pasi Eronen, Randy Turner draft-ietf-pana-pana-{04,05}.txt Resolved 71-80, 83-85, 91-93, 96-100, 103, 107 Still open 94, 95, 102, 105, 106, 108, 109 http://danforsberg.info:8080/pana-issues/.
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Since IETF 59… • Expert reviews by: • Erik Nordmark, Pasi Eronen, Randy Turner • draft-ietf-pana-pana-{04,05}.txt • Resolved • 71-80, 83-85, 91-93, 96-100, 103, 107 • Still open • 94, 95, 102, 105, 106, 108, 109 • http://danforsberg.info:8080/pana-issues/
Issue 71 • Issue: PANA-Bind-Request should include the types of post-PANA address configuration mechanisms available. • Resolution: • Post-PANA Address Configuration (PPAC) AVP carried in PBR/PBA • Options: No config, DHCP, RFC2462, RFC3456, IKEv2
Issue 72 • Issue: Currently capability discovery is not accomplished until the end of EAP authentication. Copying some bits, such as POPA types and per-packet protection capability, to PAA discovery may be useful for discovering capability mismatch early on. • Resolution: PSR now includes PPAC and Protection Capability AVPs • Warning about insecurity of discovery and spoofing attacks
Issue 73 • Issue: What type of DI will be used on DSL networks? A lower-layer per-packet identifier (source address) might not be available in all deployments. • Resolution: • Locally significant identifiers are ok (e.g., circuit id, PPP interface id) • DI does not have to be carried in an AVP • Some leftovers are creating ambiguity, hence issue 104 (need editorial fix)
Issue 74 • Issue: The current design is using PRAR and PRAA for mobility feature. We can use PBR and PBA instead, which will be better aligned with the regular signaling. • Resolution: • Use PBR/PBA instead • -----> PDI • <----- PSR • -----> PSA+SessionID • <----- PBR • -----> PBA
Issue 78 • Issue: EAP pass-through authenticator may fail authentication without an EAP-Failure message being forwarded to the EAP peer • Resolution: Send PANA-Error with PANA_UNABLE_TO_COMPLY code
Issue 79 • Issue: Should PANA support the case where EAP authentication succeeds but network access authorization fails due to, e.g., authorization rejected by a AAA proxy or authorization locally rejected by a PAA? • Resolution: PBR result codes: • PANA_SUCCESS • PANA_AUTHORIZATION_REJECTED • PANA_AUTHENTICATION_REJECTED
Issue 85 • Issue: If PRPA is replaced by POPA, PAA needs to be notified • Resolution: PaC sends PANA-Update-Request with IP-Address AVP. • Side fix: PANA-reauth MUST include MAC AVP only when PANA SA is available
Issue 98 • Issue: PANA answers may be lost. PaC/PAA should be ready to respond to retransmitted requests. • Resolution: • PANA-auth-req responses are driven by EAP • MAY respond to duplicate PANA-termination-req • SHOULD respond to any other duplicate requests • Section 4.7 and 4.11 are duplicates (bug).
Issue 100 • Issue: Due to retranmissions and window of acceptable seq. numbers, ISN_* on PAA and PaC may differ. ISNs are used in PANA_MAC_Key computation. • Resolution: • Carry Nonce values in PSR and PSA • Use nonce values instead of ISNs in key computation.
Issue 107 • Issue: Current seq. no scheme does not accommodate rexmited rseq PaC PAA (tseq,rseq) 1 <------ (x,y) 2 -->.. (y+1,x) [msg lost] 3 <------ (x+1,y) • PaC drops msg 3 because “y” was already acknowledged. • Resolution: Relax the expected rseq window to allow rexmit of rseq
Others… • Issue 75: Clarify why DI is exchanged (prevent MitM). • Issue 76: Clarify rate limiting re-authentication (coordination not necessary). • Issue 77: Overlap between pana-pana and pana-fwk (remove text from former). • Issue 80: Remove Appendix on sequence number scheme discussion. • Issue 83: Use Diameter Address type format instead of re-inventing. • Issue 84: Editorial
Others… • Issue 91: Editorial on explanatory content and flow (more actions needed under Issue 102) • Issue 92: Incorrect no. of parameters to SHA1 • Cookie = <secret-version> | HMAC_SHA1( <Device-Id of PaC> , <secret>) • Issue 93: Clarify vendor-IDs are SMI enterprise numbers (IANA) • Issue 96: EAP-TLS should be an informative reference. • Issue 97: The retransmission behavior seems quite complicated (proposals on the ML please!) • Issue 99: Missing IANA considerations section (in accordance with BCP 26). • Issue 103: Clarification on Session and Session ID.
Still Open • Issue 94 & 95: Editorial on security considerations • Issue 102: Reorganize the text flow (editorial) • Issue 105: Ambiguity on two types on reauthentication (EAP- and non-EAP-based). • Issue 106: Should rexmited msg have the same seq no? • Issue 108: Session migration from one interface to another • Issue 109: Adjusting the AVP and PANA msg field sizes
Next Steps • Fix the open issues • Publish -06 • Go to WG last call