ForCES Forwarding Element Functional Model Lily Yang Intel Corp. Nov 18, rd IETF meeting

draft-yang-forces-model-01 Co-Authors: –Lily Yang (Intel), –Joel Halpern, –Ram Gopal (Nokia), –Ram Dantu (U. of Texas) History: –53 rd IETF (Minneapolis): contribution & presentation by Ram Gopal –54 th IETF (Yokohama): joint work (v00) –Before 55 th IETF: v01

Overview Motivation of the model What is in the model Open Issues & Next Steps

Motivation CE FE capability: what FE can be FE state: what FE is now FE configuration: what FE should be FE FE Functional Model

FE Block FE Block = Abstract Base Class for FE logical functions An FE block specifies: –Block ID or name (functional type) –Textual description of the function Need a namespace: –Extensible (to allow new functions added later)

Block Library Requirements to support 8 categories of FE functions: –Forwarding –QoS –Filtering –Port –Security –High touch –Off-loaded –Vendor specific

Example of FE blocks Classifiers (from DiffServ Model) Classifier Match filter-1 Match filter-2 others output3 output2 output1 input

FE stage & Directed Graph FE Stage: an instance of an FE block in a data path –Stage id (unique within the FE) –Block Name or ID –Number of downstream stages –List of downstream stage IDs FE Directed Graph: –Interconnection of the FE stages

Two approaches in graph modeling Topological approach (DiffServ model) –No explicit info carried forward beyond next stage –Fan-out function (e.g., classifier): N branches Encoded state approach (QDDIM model) –Explicit info (preamble) can be appended and carried forward to any subsequent stages –Less branches in the graph

Open Issues/Remaining Work Data modeling language: representation –Over the wire (transport format) –On the paper (specification language) –Candidates : SMI/SPPI/ASN.1/XML/UML Topological versus Encoded State approach Modeling of the actual functions –Identify the minimum set of functions –Work on model for each one

Next Steps WG document? Data modeling language: evaluation can be done in conjunction with protocol proposals Resolve on the approach (topology/state) Define a small set of functions for initial modeling Functional modeling for each

Questions?