Forwarding and Control Element Separation (ForCES) Forwarding Element Model
RFC 5812

Internet Engineering Task Force (IETF)                        J. Halpern
Request for Comments: 5812                                          Self
Category: Standards Track                                  J. Hadi Salim
ISSN: 2070-1721                                            Znyx Networks
                                                              March 2010

           Forwarding and Control Element Separation (ForCES)
                        Forwarding Element Model

Abstract

   This document defines the forwarding element (FE) model used in the
   Forwarding and Control Element Separation (ForCES) protocol.  The
   model represents the capabilities, state, and configuration of
   forwarding elements within the context of the ForCES protocol, so
   that control elements (CEs) can control the FEs accordingly.  More
   specifically, the model describes the logical functions that are
   present in an FE, what capabilities these functions support, and how
   these functions are or can be interconnected.  This FE model is
   intended to satisfy the model requirements specified in RFC 3654.

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc5812.

Halpern & Hadi Salim         Standards Track                    [Page 1]
RFC 5812                     ForCES FE Model                  March 2010

Copyright Notice

   Copyright (c) 2010 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
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   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Halpern & Hadi Salim         Standards Track                    [Page 2]
RFC 5812                     ForCES FE Model                  March 2010

Table of Contents

   1. Introduction ....................................................5
      1.1. Requirements on the FE Model ...............................5
      1.2. The FE Model in Relation to FE Implementations .............6
      1.3. The FE Model in Relation to the ForCES Protocol ............6
      1.4. Modeling Language for the FE Model .........................7
      1.5. Document Structure .........................................8
   2. Definitions .....................................................8
   3. ForCES Model Concepts ..........................................10
      3.1. ForCES Capability Model and State Model ...................12
           3.1.1. FE Capability Model and State Model ................12
           3.1.2. Relating LFB and FE Capability and State Model .....14
      3.2. Logical Functional Block (LFB) Modeling ...................14
           3.2.1. LFB Outputs ........................................18
           3.2.2. LFB Inputs .........................................21
           3.2.3. Packet Type ........................................24
           3.2.4. Metadata ...........................................24
           3.2.5. LFB Events .........................................27
           3.2.6. Component Properties ...............................28
           3.2.7. LFB Versioning .....................................29
           3.2.8. LFB Inheritance ....................................29
      3.3. ForCES Model Addressing ...................................30
           3.3.1. Addressing LFB Components: Paths and Keys ..........32
      3.4. FE Data Path Modeling .....................................32
           3.4.1. Alternative Approaches for Modeling FE Data Paths ..33
           3.4.2. Configuring the LFB Topology .......................37
   4. Model and Schema for LFB Classes ...............................41
      4.1. Namespace .................................................42
      4.2. <LFBLibrary> Element ......................................42
      4.3. <load> Element ............................................44