6. Discovering service functions

6.1 Static configuration: an obstacle to service automation

Service function chaining techniques are a recent development. The current state of the art shows that the first developments of this service function chaining technique were based on manufacturer-specific approaches. Today, the list of service functions is statically configured. This static configuration operation consists of entering all the descriptive information for each SF function (or SF instance) in a file local to the PDP (so-called "full configuration" mode), or just the list of SF identifiers (so-called "partial configuration" mode).

In the case of partial configuration, the PDP must request a name resolution service, such as a DNS (Domain Name System) service, to retrieve other useful information...