Cisco Various proposals have been made for updating the IKE protocol. This effort has been known as 'Son of IKE (SOI)'. One thing that is missing from the discussion is an evaluation of the scope of SOI, identifying which problems it should solve. Sections of this document discuss various scenarios that are considered important for SOI. Once this scoping is done, it becomes easier to specify the requirements of the protocol. This document also discusses protocol, policy and security requirements for SOI, along with recommendations for protocol improvement in such areas as modularity, extensibility, protocol convergence and simplicity, which are important regardless of the scope of SOI.