Protocol OTP (26), One Time Password Protocol, is defined in [119,78,131].
Protocol OTP should provide (G1,2,12. (Confidentiality of the password)). Protocol S/Key (27) is defined in [77]
Protocol S/Key should provide Authentication and Secrecy (G1,2,12).
Protocol SecureID (28) is defined in [172]. Software residing on a PC or on a HW Token (smart-card like device) generates a random, one-time-use access code that changes every (say) 60 seconds. The user enters his PIN (Personal Identification Number) into the client software interface, and receives a SecurID passcode. The passcode is routed to the Server for verification, and if valid, the user gains access.
Protocol SecureID should provide Authentication and Secrecy (G1,2,12).