The SSF is the Service Swithing Function, which, associated with the CCF, provides the set of functions required for interaction between the CCF and Service Control Function. It extends the logic of the CCF to include recognition of service control triggers and interact with the SCF, manages signalling between the CCF and the SCF, modifies call/connection processing functions(in the CCF) as required to process requests for IN provided service usage under control of the SCF and is managed, updated and/orotherwise administered by an SMF.