Optimized Service Function Chaining

This draft investigates possibilities to use so-called 'transport- derived service function forwarders' (tSFFs) that uses existing transport information for explicit service path information. The draft discusses two such possibilities, focusing on realization of efficient chaining over single transport networks. In the first one, the transport network is SDN-based. The second one introduces and explains a specific service request routing (SRR) function to support URL-level routing of service requests.