1. PlutoPlus: Policy and PKI Plans for FY00 Sheila Frankel Systems and Network Security Group Computer Security Division NIST sheila.frankel@nist.gov

2. Nov. 30, 19992 PlutoPlus ‘99 Peer authentication : –pre-shared secret keys Policy: –Same policy for all peers –Initiator proposes single policy –Responder must accept proposed policy

3. Nov. 30, 19993 Y2K PlutoPlus Peer authentication : choice of pre-shared secret keys, digital signature, or public key encryption Policy: –Flexible policy database –Different policies for different peers –Initiator proposes multiple policies –Responder selects most preferable policy

4. Nov. 30, 19994 What Constitutes Policy? Encryption algorithm: DES, 3DES, Blowfish, IDEA, RC5 Encryption Key Length Authentication algorithm: HMAC-MD5, HMAC-SHA1 Diffie-Hellman group: prime with 96, 128, or 192 bytes Encapsulation mode: tunnel or transport

5. Nov. 30, 19995 Policy Database Elements (cont’d) Peer authentication: pre-shared secret key, digital signature, public key encryption Negotiated Security Association’s Lifetime: seconds and/or kilobytes protected Perfect Forward Secrecy for negotiated keys

6. Nov. 30, 19996 Why PKI Interaction? Peer authentication with pre-shared keys: –pre-shared secret key used to prove identity –limited scalability –opportunistic encryption impossible Peer authentication with PKI –digital signature or public key used to prove identity –scalable –opportunistic encryption possible