Forwarding and Control Element Separation

Document Charter Forwarding and Control Element Separation WG (forces)
Title Forwarding and Control Element Separation
Last updated 2015-10-14
State Approved
WG State Concluded
IESG Responsible AD Adrian Farrel
Charter Edit AD Adrian Farrel
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The ForCES working group has created a framework, requirements, a solution
protocol, a logical function block library, and other associated documents in
support of Forwarding and Control Element Separation.

Drawing on the experience gained from developing the standards and from
many efforts using this architecture, the ForCES working group is now
working on a set of additions to the model, the protocol, and the libraries.

The following 5 work items are the chartered tasks of this working group:

o Extensions to Model and Protocol

  This work is to address a set of extensions to the base model and
protocol   resulting in updates to RFCs 5810 and 5812. This effort will
produce 2   Standards Track documents (one for the model and another for
the protocol).

  The model extensions will:
  1. Allow compound metadata
  2. Allow optional default values for datatypes
  3. Allow optional access-type for datatypes inside complex components
  4. Define new base type: Bitmap
  5. Define new events to monitor states.

  The protocol extensions will:
  1. Support table range query
  2. Support table append
  3. Define additional return codes to reduce ambiguity
  4. Define data packing rule for bitmap datatype.

o Inter-FE Connectivity

  ForCES processing is often spread across multiple Forwarding Elements
(FEs).   The original framework identified the interface between FEs as
the "Fi"   reference point. Protocol and Logical Function Block
(LFB) mechanisms to   carry metadata across the Fi interface are
needed.  This effort will produce   a standards track document
defining the protocol on the wire to address this   need, and the LFBs
used to represent the Interfaces for sending and receiving   such
information. It is expected that this work will draw heavily on existing  
protocol and LFB definitions.

o Parallelization

  An FE can implement an LFB chain with parallelization, but the currently-
  defined mechanism has no means to represent when synchronization is
needed,   or to allow the CE to specify where it believes such parallelism
is useful.   This work item will produce a single standards track document
to improve the   handling of this case.

o Subsidiary Management

  Deployment experience has demonstrated the value of using ForCES to
control   the Forwarding Element Manager (FEM) by creating an LFB to
represent its   function using the same encoding rules as for any other
LFB. This allows it   to be controlled by the same Control Element (CE).
This work item assumes the   presence of an initially booted FE whose
configuration could then be updated   at runtime via an FEM LFB for
runtime config purposes (e.g., by adding a new   CE and its associated IP
address). This work item can also be useful in   addressing control of
virtual FEs where individual FEM Managers can be   addressed to control
the creation, configuration, and resource assignment of   such virtual FEs
within a physical FE. This work would result in a standards   track LFB
FEM library RFC.

In addition to the specific work items listed above, the working group will
allow discussions and review work of how to use ForCES to model topics of
interest to Network Function Virtualization, I2RS, or OpenFlow. It is
understood that the primary responsibility for such documents lives with other
working groups, individual contributions, or other standards bodies.