Skip to main content

A YANG Data Model for Routing Information Base (RIB)
draft-ietf-i2rs-rib-data-model-00

The information below is for an old version of the document.
Document Type
This is an older version of an Internet-Draft that was ultimately published as RFC 8431.
Authors Lixing Wang , Hariharan Ananthakrishnan , Mach Chen , Amit Dass , Sriganesh Kini , Nitin Bahadur
Last updated 2015-04-06 (Latest revision 2015-04-03)
Replaces draft-wang-i2rs-rib-data-model
RFC stream Internet Engineering Task Force (IETF)
Formats
Reviews
Additional resources Mailing list discussion
Stream WG state WG Document
Document shepherd (None)
IESG IESG state Became RFC 8431 (Proposed Standard)
Consensus boilerplate Unknown
Telechat date (None)
Responsible AD (None)
Send notices to (None)
draft-ietf-i2rs-rib-data-model-00
Network Working Group                                            L. Wang
Internet-Draft                                                    Huawei
Intended status: Standards Track                      H. Ananthakrishnan
Expires: October 5, 2015                                   Packet Design
                                                                 M. Chen
                                                                  Huawei
                                                                 A. Dass
                                                                 S. Kini
                                                                Ericsson
                                                              N. Bahadur
                                                       Bracket Computing
                                                          April 03, 2015

          A YANG Data Model for Routing Information Base (RIB)
                   draft-ietf-i2rs-rib-data-model-00

Abstract

   This document defines a YANG data model for Routing Information Base
   (RIB) that aligns with the I2RS RIB information model.

Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on October 5, 2015.

Wang, et al.             Expires October 5, 2015                [Page 1]
Internet-Draft                   RIB DM                       April 2015

Copyright Notice

   Copyright (c) 2015 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
   to this document.  Code Components extracted from this document must
   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.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Definitions and Acronyms  . . . . . . . . . . . . . . . .   3
     1.2.  Tree Diagrams . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Model Structure . . . . . . . . . . . . . . . . . . . . . . .   3
     2.1.  RIB Capability  . . . . . . . . . . . . . . . . . . . . .   5
     2.2.  Routing Instance and Rib  . . . . . . . . . . . . . . . .   6
     2.3.  Route . . . . . . . . . . . . . . . . . . . . . . . . . .   7
     2.4.  Nexthop . . . . . . . . . . . . . . . . . . . . . . . . .   8
     2.5.  Notifications . . . . . . . . . . . . . . . . . . . . . .  12
   3.  YANG Modules  . . . . . . . . . . . . . . . . . . . . . . . .  14
   4.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  37
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .  37
   6.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  37
     6.1.  Normative References  . . . . . . . . . . . . . . . . . .  37
     6.2.  Informative References  . . . . . . . . . . . . . . . . .  37
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  37

1.  Introduction

   The Interface to the Routing System (I2RS)
   [I-D.ietf-i2rs-architecture] provides read and write access to the
   information and state within the routing process that exists inside
   the routing elements, this is achieved via the protocol message
   exchange between I2RS clients and I2RS agents associated with the
   routing system.  One of the functions of I2RS is to read and write
   data of Routing Information Base (RIB).
   [I-D.ietf-i2rs-usecase-reqs-summary] introduces a set of RIB use
   cases and the RIB information model is defined in
   [I-D.ietf-i2rs-rib-info-model].

Wang, et al.             Expires October 5, 2015                [Page 2]
Internet-Draft                   RIB DM                       April 2015

   This document defines a YANG [RFC6020][RFC6021] data model for the
   RIB that satisfies the RIB use cases and aligns with the RIB
   information model.

1.1.  Definitions and Acronyms

   RIB: Routing Information Base

   Information Model (IM): An abstract model of a conceptual domain,
   independent of a specific implementation or data representation.

1.2.  Tree Diagrams

   A simplified graphical representation of the data model is used in
   this document.  The meaning of the symbols in these diagrams is as
   follows:

   o  Brackets "[" and "]" enclose list keys.

   o  Abbreviations before data node names: "rw" means configuration
      (read-write) and "ro" state data (read-only).

   o  Symbols after data node names: "?" means an optional node and "*"
      denotes a "list" and "leaf-list".

   o  Parentheses enclose choice and case nodes, and case nodes are also
      marked with a colon (":").

   o  Ellipsis ("...") stands for contents of subtrees that are not
      shown.

2.  Model Structure

   The following figure shows an overview of structure tree of the i2rs-
   rib module.  To give a whole view of the structure tree, some details
   of the tree are omitted.  The detail are introduced in the following
   sub-sections.

      module: i2rs-rib
         +--rw nexthop-capacity
         |  ...
         +--rw nexthop-tunnel-encap-capacity
         |  ...
         +--rw routing-instance
            +--rw instance-name     string
            +--rw interface-list* [name]
            |  +--rw name        if:interface-ref
            +--rw router-id?        yang:dotted-quad

Wang, et al.             Expires October 5, 2015                [Page 3]
Internet-Draft                   RIB DM                       April 2015

            +--rw rib-list* [rib-name]
               +--rw rib-name               string
               +--rw rib-family             rib-family-def
               +--rw enable-ip-rpf-check?        boolean
               +--rw route-list* [route-index]
                  +--rw route-index                uint64
                  +--rw route-type                 route-type-def
                  +--rw match
                  |  +--rw (rib-route-type)?
                  |     +--:(ipv4)
                  |     |  ...
                  |     +--:(ipv6)
                  |     |  ...
                  |     +--:(mpls-route)
                  |     |  ...
                  |     +--:(mac-route)
                  |     |  ...
                  |     +--:(interface-route)
                  |        ...
                  +--rw nexthop
                  |  +--rw nexthop-id           uint32
                  |  +--rw (nexthop-type)?
                  |     +--:(nexthop-base)
                  |     |  ...
                  |     +--:(nexthop-protection)
                  |     |  ...
                  |     +--:(nexthop-load-balance)
                  |     |  ...
                  |     +--:(nexthop-replicate)
                  |        ...
                  +--rw route-statistic
                  |  ...
                  +--rw route-attributes
                  |  +--rw route-preference           uint32
                  |  +--rw local-only                 boolean
                  |  +--rw address-family-route-attributes
                  |     +--rw (route-type)?
                  |        +--:(ip-route-attributes)
                  |        +--:(mpls-route-attributes)
                  |        +--:(eThernet-route-attributes)
                  +--rw route-vendor-attributes
      notifications:
         +---n nexthop-resolution-status-change
         |  +--ro nexthop
         |  |  +--ro nexthop-id           uint32
         |  |  +--ro (nexthop-type)?
         |  |     +--:(nexthop-base)
         |  |     |  ...

Wang, et al.             Expires October 5, 2015                [Page 4]
Internet-Draft                   RIB DM                       April 2015

         |  |     +--:(nexthop-protection)
         |  |     |  ...
         |  |     +--:(nexthop-load-balance)
         |  |     |  ...
         |  |     +--:(nexthop-replicate)
         |  |        ...
         |  +--ro nexthop-state        nexthop-state-def
         +---n route-change
            +--ro instance-name            string
            +--ro rib-name                 string
            +--ro rib-family               rib-family-def
            +--ro route-index              uint64
            +--ro route-type               route-type-def
            +--ro match
            |  +--ro (rib-route-type)?
            |     +--:(ipv4)
            |     |  ...
            |     +--:(ipv6)
            |     |  ...
            |     +--:(mpls-route)
            |     |  +--ro mpls-label              uint32
            |     +--:(mac-route)
            |     |  +--ro mac-address             uint32
            |     +--:(interface-route)
            |        +--ro interface-identifier if:interface-ref
            +--ro route-installed-state route-installed-state-def
            +--ro route-state           route-state-def
            +--ro route-reason          route-reason-def

                  Figure 1 Overview of I2RS module

2.1.  RIB Capability

   RIB capability negotiation is very important because not all of the
   hardware will be able to support all kinds of nexthops and there
   should be a limitation on how many levels of lookup can be
   practically performed.  Therefore, a RIB data model MUST specify a
   way for an external entity to learn about the functional capabilities
   of a network device.

   At the same time, nexthop chains can be used to specify multiple
   headers over a packet, before that particular packet is forwarded.
   Not every network device will be able to support all kinds of nexthop
   chains along with the arbitrary number of headers which are chained
   together.  The RIB data model MUST provide a way to expose the
   nexthop chaining capability supported by a given network device.

Wang, et al.             Expires October 5, 2015                [Page 5]
Internet-Draft                   RIB DM                       April 2015

   The structure of the next-hop-capacity and the nexthop-tunnel-encap-
   capacity is shown in the following figure:

   Editor Notes: this version only includes the nexthop-hop and nexthop-
   tunnel-encap capabilities, there may also need to define RIB
   capabilities in future revision.

      +--rw nexthop-capacity
      |  +--rw support-tunnel?         boolean
      |  +--rw support-chains?         boolean
      |  +--rw support-list-of-list?   boolean
      |  +--rw support-replication?    boolean
      |  +--rw support-weighted?       boolean
      |  +--rw support-protection?     boolean
      |  +--rw lookup-limit?           uint8
      +--rw nexthop-tunnel-encap-capacity
      |  +--rw support-ipv4?    boolean
      |  +--rw support-ipv6?    boolean
      |  +--rw support-mpls?    boolean
      |  +--rw support-gre?     boolean
      |  +--rw support-vxlan?   boolean
      |  +--rw support-nvgre?   boolean

             Figure 2 RIB Capability

2.2.  Routing Instance and Rib

   A routing instance, in the context of the RIB information model, is a
   collection of RIBs, interfaces, and routing protocol parameters.  A
   routing instance creates a logical slice of the router and can allow
   multiple different logical slices; across a set of routers; to
   communicate with each other.  And the routing protocol parameters
   control the information available in the RIBs.  More detail about
   routing instance can be found in Section 2.2 of
   [I-D.ietf-i2rs-rib-info-model].

   As described in [I-D.ietf-i2rs-rib-info-model], there will be
   multiple routing instances for a router.  At the same time, for a
   routing instance, there would be multiple RIBs as well.  Therefore,
   this model uses "list" to express the RIBs.  The structure tree is
   shown as following figure.

Wang, et al.             Expires October 5, 2015                [Page 6]
Internet-Draft                   RIB DM                       April 2015

      +--rw routing-instance
         +--rw instance-name     string
         +--rw interface-list* [name]
         |  +--rw name        if:interface-ref
         +--rw router-id?        yang:dotted-quad
         +--rw rib-list* [rib-name]
            +--rw rib-name               string
            +--rw rib-family             rib-family-def
            +--rw enable-ip-rpf-check?   boolean
            +--rw route-list* [route-index]
               ... (refer to sec.2.3)

             Figure 3 Routing Instance

2.3.  Route

   A route is essentially a match condition and an action following that
   match.  The match condition specifies the kind of route (e.g., IPv4,
   MPLS, MAC, Interface etc.) and the set of fields to match on.

   According to the definition in [I-D.ietf-i2rs-rib-info-model], a
   route MUST associate with the following attributes:

   o  ROUTE_PREFERENCE: See Section 2.3 of
      [I-D.ietf-i2rs-rib-info-model].

   o  ACTIVE: Indicates whether a route is fully resolved and is a
      candidate for selection.

   o  INSTALLED: Indicates whether the route got installed in the FIB.

   In addition, a route can associate with one or more optional route
   attributes(e.g., route-vendor-attributes).

   For a RIB, there will have a number of routes, so the routes are
   expressed as a list under the rib list.

Wang, et al.             Expires October 5, 2015                [Page 7]
Internet-Draft                   RIB DM                       April 2015

 +--rw route-list* [route-index]
    +--rw route-index                uint64
    +--rw route-type                 route-type-def
    +--rw match
    |  +--rw (rib-route-type)?
    |     +--:(ipv4)
    |     |  +--rw ipv4
    |     |     +--rw ipv4-route-type                  ip-route-type-def
    |     |     +--rw (ip-route-type)?
    |     |        +--:(destination-ipv4-address)
    |     |        |  +--rw destination-ipv4-prefix inet:ipv4-prefix
    |     |        +--:(source-ipv4-address)
    |     |        |  +--rw source-ipv4-prefix         inet:ipv4-prefix
    |     |        +--:(destination-source-ipv4-address)
    |     |           +--rw destination-source-ipv4-address
    |     |              +--rw destination-ipv4-prefix inet:ipv4-prefix
    |     |              +--rw source-ipv4-prefix inet:ipv4-prefix
    |     +--:(ipv6)
    |     |  +--rw ipv6
    |     |     +--rw ipv6-route-type                  ip-route-type-def
    |     |     +--rw (ip-route-type)?
    |     |        +--:(destination-ipv6-address)
    |     |        |  +--rw destination-ipv6-prefix inet:ipv6-prefix
    |     |        +--:(source-ipv6-address)
    |     |        |  +--rw source-ipv6-prefix        inet:ipv6-prefix
    |     |        +--:(destination-source-ipv6-address)
    |     |           +--rw destination-source-ipv6-address
    |     |              +--rw destination-ipv6-prefix inet:ipv6-prefix
    |     |              +--rw source-ipv6-prefix inet:ipv6-prefix
    |     +--:(mpls-route)
    |     |  +--rw mpls-label              uint32
    |     +--:(mac-route)
    |     |  +--rw mac-address             uint32
    |     +--:(interface-route)
    |        +--rw interface-identifier        if:interface-ref
    +--rw nexthop
       ... (refer to sec.2.4)

                          Figure 4 Route

2.4.  Nexthop

   A nexthop represents an object resulting from a route lookup.  As
   illustrated in Section 2.4 of [I-D.ietf-i2rs-rib-info-model], to
   support various of use cases (e.g., load balance, protection,
   multicast or the combination of them), the nexthop is modelled as a
   multi-level structure and supports recursion.  The first level of the
   nexthop includes the following four types:

Wang, et al.             Expires October 5, 2015                [Page 8]
Internet-Draft                   RIB DM                       April 2015

   o  Base: The "base" nexthop itself is a hierarchical structure, it is
      the base of all other nexthop types.  The first level of the base
      nexthop includes special-nexthop and nexthop-chain.  The nexthop-
      chain can have one or more nexthop chain members, each member is
      one of the four types (as listed below) of specific nexthop.
      Other first level nexthop (e.g., load-balance, protection and
      replicate) will finally be iterated to a "base" nexthop.

      *  nexthop-id

      *  egress-interface

      *  logical-tunnel

      *  tunnel-encap

   o  Load-balance: Designed for load-balance case.

   o  Protection: Designed for protection scenario where it normally
      will have primary and standby nexthop.

   o  Replicate: Designed for multiple destinations forwarding.

   The structure tree of nexthop is shown in the following figures.

Wang, et al.             Expires October 5, 2015                [Page 9]
Internet-Draft                   RIB DM                       April 2015

      +--rw nexthop
      |  +--rw nexthop-id           uint32
      |  +--rw (nexthop-type)?
      |     +--:(nexthop-base)
      |     |  +--rw nexthop-base
      |     |     +--rw nexthop-chain* [nexthop-chain-id]
      |     |        +--rw nexthop-chain-id        uint32
      |     |        +--rw (nexthop-chain-type)?
      |     |              ... (refer to Figure 6)
      |     +--:(nexthop-protection)
      |     |  +--rw nexthop-protection-list* [nexthop-protection-id]
      |     |     +--rw nexthop-protection-id     uint32
      |     |     +--rw nexthop-preference       nexthop-preference-def
      |     |     +--rw nexthop                  nexthop-ref
      |     +--:(nexthop-load-balance)
      |     |  +--rw nexthop-lb
      |     |     +--rw nexthop-lbs* [nexthop-lbs-id]
      |     |        +--rw nexthop-lbs-id        uint32
      |     |        +--rw nhop-lb-weight        nhop-lb-weight-def
      |     |        +--rw nexthop-lb-member        nexthop-ref
      |     +--:(nexthop-replicate)
      |        +--rw nexthop-replicate
      |           +--rw nexthop-replicates* [nexthop-replicates-id]
      |              +--rw nexthop-replicates-id        uint32
      |              +--rw nexthop-replicate?        nexthop-ref

                  Figure 5 Nexhop

   Figure 6 (as shown blow) is a sub-tree of nexthop, it's under the
   nexthop chain node.

   +--rw (nexthop-chain-type)?
      +--:(nexthop-chain-member-special)
      |  +--rw nexthop-chain-member-special
      |     +--rw nexthop-chain-member-special? special-nexthop-def
      +--:(nexthop-chain-member-identifier)
      |  +--rw (nexthop-identifier-type)?
      |     +--:(nexthop-chain-name)
      |     |  +--rw nexthop-chain-name         string
      |     +--:(nexthop-chain-id)
      |        +--rw nexthop-chain-id           uint32
      +--:(egress-interface-next-hop)
      |  +--rw outgoing-interface               if:interface-ref
      +--:(ipv4-address-next-hop)
      |  +--rw next-hop-ipv4-address            inet:ipv4-address
      +--:(ipv6-address-next-hop)
      |  +--rw next-hop-ipv6-address            inet:ipv6-address
      +--:(egress-interface-ipv4-next-hop)

Wang, et al.             Expires October 5, 2015               [Page 10]
Internet-Draft                   RIB DM                       April 2015

      |  +--rw next-hop-egress-interface-ipv4-address
      |     +--rw outgoing-interface            if:interface-ref
      |     +--rw next-hop-egress-ipv4-address inet:ipv4-address
      +--:(egress-interface-ipv6-next-hop)
      |  +--rw next-hop-egress-interface-ipv6-address
      |     +--rw outgoing-interface           if:interface-ref
      |     +--rw next-hop-egress-ipv6-address inet:ipv4-address
      +--:(egress-interface-mac-next-hop)
      |  +--rw next-hop-egress-interface-mac-address
      |     +--rw outgoing-interface        if:interface-ref
      |     +--rw ieee-mac-address          uint32
      +--:(tunnel-encap-next-hop)
      |  +--rw tunnel-encap
      |     +--rw (tunnel-type)?
      |     |  +--:(ipv4)
      |     |  |  +--rw source-ipv4-address inet:ipv4-address
      |     |  |  +--rw destination-ipv4-address inet:ipv4-address
      |     |  |  +--rw protocol                 uint8
      |     |  |  +--rw ttl?                     uint8
      |     |  |  +--rw dscp?                    uint8
      |     |  +--:(ipv6)
      |     |  |  +--rw source-ipv6-address inet:ipv6-address
      |     |  |  +--rw destination-ipv6-address inet:ipv6-address
      |     |  |  +--rw next-header              uint8
      |     |  |  +--rw traffic-class?           uint8
      |     |  |  +--rw flow-label?              uint16
      |     |  |  +--rw hop-limit?               uint8
      |     |  +--:(mpls)
      |     |  |  +--rw (mpls-action-type)?
      |     |  |     +--:(mpls-push)
      |     |  |     |  +--rw mpls-push          boolean
      |     |  |     |  +--rw mpls-label         uint32
      |     |  |     |  +--rw s-bit?             boolean
      |     |  |     |  +--rw tos-value?         uint8
      |     |  |     |  +--rw ttl-value?         uint8
      |     |  |     +--:(mpls-pop)
      |     |  |        +--rw mpls-pop           boolean
      |     |  |        +--rw ttl-action?        uint8
      |     |  +--:(gre)
      |     |  |  +--rw gre-ip-destination        inet:ipv4-address
      |     |  |  +--rw gre-protocol-type         inet:ipv4-address
      |     |  |  +--rw gre-key?                  uint64
      |     |  +--:(nvgre)
      |     |     +--rw (nvgre-type)?
      |     |     |  +--:(ipv4)
      |     |     |  |  +--rw source-ipv4-address inet:ipv4-address
      |     |     |  |  +--rw destination-ipv4-address inet:ipv4-address
      |     |     |  |  +--rw protocol                 uint8

Wang, et al.             Expires October 5, 2015               [Page 11]
Internet-Draft                   RIB DM                       April 2015

      |     |     |  |  +--rw ttl?                     uint8
      |     |     |  |  +--rw dscp?                    uint8
      |     |     |  +--:(ipv6)
      |     |     |     +--rw source-ipv6-address inet:ipv6-address
      |     |     |     +--rw destination-ipv6-address inet:ipv6-address
      |     |     |     +--rw next-header              uint8
      |     |     |     +--rw traffic-class?           uint8
      |     |     |     +--rw flow-label?              uint16
      |     |     |     +--rw hop-limit?               uint8
      |     |     +--rw virtual-subnet-id           uint32
      |     |     +--rw flow-id?                    uint16
      |     +--rw outgoing-interface?         string
      +--:(logical-tunnel-next-hop)
      |  +--rw logical-tunnel
      |     +--rw tunnel-type        tunnel-type-def
      |     +--rw tunnel-name        string
      +--:(rib-name)
          +--rw rib-name?                             string

                  Figure 6 Nexthop Chain

2.5.  Notifications

   Asynchronous notifications are sent by the RIB manager of a network
   device to an external entity when some event triggers on the network
   device.  A RIB data-model MUST support sending 2 kind of asynchronous
   notifications.

   1.  Route change notification:

   o Installed (Indicates whether the route got installed in the FIB) ;

   o Active (Indicates whether a route is fully resolved and is a
   candidate for selection) ;

   o Reason - E.g.  Not authorized

   2.  Nexthop resolution status notification

   Nexthops can be fully resolved nexthops or an unresolved nexthop.

   A resolved nexthop has adequate level of information to send the
   outgoing packet towards the destination by forwarding it on an
   interface of a directly connected neighbor.

   An unresolved nexthop is something that requires the RIB manager to
   determine the final resolved nexthop.  For example, in a case when a
   nexthop could be an IP address.  The RIB manager would resolve how to

Wang, et al.             Expires October 5, 2015               [Page 12]
Internet-Draft                   RIB DM                       April 2015

   reach that IP address, e.g. by checking if that particular IP is
   address reachable by regular IP forwarding or by a MPLS tunnel or by
   both.  If the RIB manager cannot resolve the nexthop, then the
   nexthop remains in an unresolved state and is NOT a suitable
   candidate for installation in the FIB.

   The structure tree of notifications is shown in the following figure.

 notifications:
    +---n nexthop-resolution-status-change
    |  +--ro nexthop
    |  |  +--ro nexthop-id           uint32
    |  |  +--ro (nexthop-type)?
    |  |     +--:(nexthop-base)
    |  |     |  +--ro nexthop-base
    |  |     |     +--ro nexthop-chain* [nexthop-chain-id]
    |  |     |        +--ro nexthop-chain-id     uint32
    |  |     |        +--ro (nexthop-chain-type)?
    |  |     |           ...
    |  |     +--:(nexthop-protection)
    |  |     |  +--ro nexthop-protection-list* [nexthop-protection-id]
    |  |     |     +--ro nexthop-protection-id     uint32
    |  |     |     +--ro nexthop-preference       nexthop-preference-def
    |  |     |     +--ro rw nexthop                  nexthop-ref
    |  |     +--:(nexthop-load-balance)
    |  |     |  +--ro nexthop-lb
    |  |     |     +--ro nexthop-lbs* [nexthop-lbs-id]
    |  |     |        +--ro nexthop-lbs-id       uint32
    |  |     |        +--ro nhop-lb-weight     nhop-lb-weight-def
    |  |     |        +--ro nexthop-lb-member nexthop-ref
    |  |     +--:(nexthop-replicate)
    |  |        +--ro nexthop-replicate
    |  |           +--ro nexthop-replicates* [nexthop-replicates-id]
    |  |              +--ro nexthop-replicates-id     uint32
    |  |              +--ro nexthop-replicate?       nexthop-ref
    |  +--ro nexthop-state     nexthop-state-def
    +---n route-change
       +--ro instance-name            string
       +--ro rib-name                 string
       +--ro rib-family               rib-family-def
       +--ro route-index              uint64
       +--ro route-type               route-type-def
       +--ro match
       |  +--ro (rib-route-type)?
       |     +--:(ipv4)
       |     |  +--ro ipv4
       |     |     ...
       |     +--:(ipv6)

Wang, et al.             Expires October 5, 2015               [Page 13]
Internet-Draft                   RIB DM                       April 2015

       |     |  +--ro ipv6
       |     |     ...
       |     +--:(mpls-route)
       |     |  +--ro mpls-label              uint32
       |     +--:(mac-route)
       |     |  +--ro mac-address             uint32
       |     +--:(interface-route)
       |        +--ro interface-identifier if:interface-ref
       +--ro route-installed-state route-installed-state-def
       +--ro route-state              route-state-def
       +--ro route-reason             route-reason-def

                  Figure 7 Notifications

3.  YANG Modules

//<code begins> file "i2rs rib@2015-03-09.yang"

module i2rs-rib {
  namespace "urn:TBD1:params:xml:ns:yang:rt:i2rs:rib";
    // replace with iana namespace when assigned
    prefix "i2rs-rib";

  import ietf-inet-types {
    prefix inet;
    //rfc6991
  }

  import ietf-interfaces {
    prefix "if";
  }

  import ietf-routing {
    prefix "rt";
  }

  organization
    "TBD2";
  contact
     "email: wang_little_star@sina.com
      email: hari@packetdesign.com
      email: mach.chen@huawei.com
      email: amit.dass@ericsson.com
      email: sriganesh.kini@ericsson.com
      email: nitin_bahadur@yahoo.com";

  description
    "This module defines a YANG data model for

Wang, et al.             Expires October 5, 2015               [Page 14]
Internet-Draft                   RIB DM                       April 2015

     Routing Information Base (RIB) that aligns
     with the I2RS RIB information model.
     ";

  revision "2015-04-03" {
    description "initial revision";
    reference "draft-ietf-i2rs-rib-info-model-06";
  }

  container nexthop-capacity{
    leaf support-tunnel{
      type boolean;
    }
    leaf support-chains{
      type boolean;
    }
    leaf support-list-of-list{
      type boolean;
    }
    leaf support-replication{
      type boolean;
    }
    leaf support-weighted{
      type boolean;
    }
    leaf support-protection{
      type boolean;
    }
    leaf lookup-limit{
      type uint8;
    }
  }

  container nexthop-tunnel-encap-capacity{
    leaf support-ipv4{
      type boolean;
    }
    leaf support-ipv6{
      type boolean;
    }
    leaf support-mpls{
      type boolean;
    }
    leaf support-gre{
      type boolean;
    }
    leaf support-vxlan{
      type boolean;

Wang, et al.             Expires October 5, 2015               [Page 15]
Internet-Draft                   RIB DM                       April 2015

    }
    leaf support-nvgre{
      type boolean;
    }
  }

  // Identities and Type Definitions
  identity mpls-action {
    description
      "The mpls-action. ";
  }

  identity push {
    base "mpls-action";
  }

  identity pop {
    base "mpls-action";
  }

  identity swap {
    base "mpls-action";
  }

  typedef mpls-action-def {
    type identityref {
      base "mpls-action";
    }
  }

  identity special-nexthop {
    description
      "special-nexthop. ";
  }

  identity discard {
    base "special-nexthop";
  }

  identity discard-with-error {
    base "special-nexthop";
  }

  identity receive {
    base "special-nexthop";
  }

  identity cos-value {

Wang, et al.             Expires October 5, 2015               [Page 16]
Internet-Draft                   RIB DM                       April 2015

    base "special-nexthop";
  }

  typedef special-nexthop-def {
    type identityref {
      base "special-nexthop";
    }
  }

  identity ip-route-type {
    description
      "The ip route type. ";
  }

  identity src {
    base "ip-route-type";
  }

  identity dest {
    base "ip-route-type";
  }

  identity dest-src {
    base "ip-route-type";
  }

  typedef ip-route-type-def {
    type identityref {
      base "ip-route-type";
    }
  }

  identity rib-family {
    description
      "The rib-family.";
  }

  identity ipv4-rib-family {
    base "rib-family";
  }

  identity ipv6-rib-family {
    base "rib-family";
  }

  identity mpls-rib-family {
    base "rib-family";
  }

Wang, et al.             Expires October 5, 2015               [Page 17]
Internet-Draft                   RIB DM                       April 2015

  identity ieee-mac-rib-family {
    base "rib-family";
  }

  typedef rib-family-def {
    type identityref {
      base "rib-family";
    }
  }

  identity route-type {
    description "The route type. ";
  }

  identity ipv4-route {
    base "route-type";
  }

  identity ipv6-route {
    base "route-type";
  }

  identity mpls-route {
    base "route-type";
  }

  identity ieee-mac {
    base "route-type";
  }

  identity interface {
    base "route-type";
  }

  typedef route-type-def {
    type identityref {
      base "route-type";
    }
  }

  identity tunnel-type {
    description
      "The tunnel type.";
  }

  identity ipv4-tunnel {
    base "tunnel-type";
    description

Wang, et al.             Expires October 5, 2015               [Page 18]
Internet-Draft                   RIB DM                       April 2015

      "IPv4 tunnel type";
  }

  identity ipv6-tunnel {
    base "tunnel-type";
    description
      "IPv6 Tunnel type";
  }

  identity mpls-tunnel {
    base "tunnel-type";
    description
      "MPLS tunnel type";
  }

  identity gre-tunnel {
    base "tunnel-type";
    description
      "GRE tunnel type";
  }

  identity vxlan-tunnel {
    base "tunnel-type";
    description
      "VxLAN tunnel type";
  }

  identity nvgre-tunnel {
    base "tunnel-type";
    description
      "NVGRE tunnel type";
  }

  typedef tunnel-type-def {
    type identityref {
      base "tunnel-type";
    }
  }

  identity route-state {
    description
      "The route state.";
  }

  identity active {
    base "route-state";
  }

Wang, et al.             Expires October 5, 2015               [Page 19]
Internet-Draft                   RIB DM                       April 2015

  identity inactive {
    base "route-state";
  }

  typedef route-state-def {
    type identityref {
      base "route-state";
    }
  }

  identity nexthop-state {
    description
      "The nexthop state.";
  }

  identity resolved {
    base "nexthop-state";
  }

  identity unresolved {
    base "nexthop-state";
  }

  typedef nexthop-state-def {
    type identityref {
      base "nexthop-state";
    }
  }

  identity route-installed-state {
    description
      "The route installed state. ";
  }

  identity uninstalled {
    base "route-installed-state";
  }

  identity Installed {
    base "route-installed-state";
  }

  typedef route-installed-state-def {
    type identityref {
      base "route-installed-state";
    }
  }

Wang, et al.             Expires October 5, 2015               [Page 20]
Internet-Draft                   RIB DM                       April 2015

  identity route-reason {
    description
      "The reason of invalid route. ";
  }

  identity low-preference {
    base "route-reason";
    description
      "Low preference";
  }

  identity unresolved-nexthop {
    base "route-reason";
    description
      "Unresolved nexthop";
  }

  identity higher-metric {
    base "route-reason";
    description
      "Higher metric";
  }

  typedef route-reason-def {
    type identityref {
      base "route-reason";
    }
  }

  typedef nexthop-preference-def {
    description
      "Nexthop-preference is used for protection schemes.
       It is an integer value between 1 and 99.  A lower
       value indicates higher preference.  To download a
       primary/standby/tertiary group to the FIB, the
       nexthops that are resolved and have two highest
       preferences are selected.";
    type uint8 {
      range "1..99";
    }
  }
  typedef nhop-lb-weight-def {
    description
      "Nhop-lb-weight is a number between 1 and 99.";
    type uint8 {
      range "1..99";
    }
  }

Wang, et al.             Expires October 5, 2015               [Page 21]
Internet-Draft                   RIB DM                       April 2015

  typedef nexthop-ref {
    type leafref {
      path  "/i2rs-rib:routing-instance/i2rs-rib:rib-list" +
            "/i2rs-rib:route-list/i2rs-rib:nexthop/i2rs-rib:nexthop-id";
    }
  }

  //Groupings

  grouping route-prefix{
    description
      "The common attributes used for all routes";
    leaf route-index {
      type uint64 ;
      mandatory true;
    }
    leaf route-type {
      type route-type-def ;
      mandatory true;
    }
    container match {
      choice rib-route-type {
        case ipv4 {
          description
            "Match on destination IP address in the IPv4 header";
          container ipv4{
            leaf ipv4-route-type {
              type ip-route-type-def ;
              mandatory true;
            }
            choice ip-route-type {
              case destination-ipv4-address {
                leaf destination-ipv4-prefix {
                  type inet:ipv4-prefix;
                  mandatory true;
                }
              }
              case source-ipv4-address {
                leaf source-ipv4-prefix {
                  type inet:ipv4-prefix;
                  mandatory true;
                }
              }
              case destination-source-ipv4-address {
                container destination-source-ipv4-address {
                  leaf destination-ipv4-prefix {
                    type inet:ipv4-prefix;
                    mandatory true;

Wang, et al.             Expires October 5, 2015               [Page 22]
Internet-Draft                   RIB DM                       April 2015

                  }
                  leaf source-ipv4-prefix {
                    type inet:ipv4-prefix;
                    mandatory true;
                  }
                }
              }
            }
          }
        }
        case ipv6 {
          description
            "Match on destination IP address in the IPv6 header";
          container ipv6 {
            leaf ipv6-route-type {
              type ip-route-type-def ;
              mandatory true;
            }
            choice ip-route-type {
              case destination-ipv6-address {
                leaf destination-ipv6-prefix {
                  type inet:ipv6-prefix;
                  mandatory true;
                }
              }
              case source-ipv6-address {
                leaf source-ipv6-prefix {
                  type inet:ipv6-prefix;
                  mandatory true;
                }
              }
              case destination-source-ipv6-address {
                container destination-source-ipv6-address {
                  leaf destination-ipv6-prefix {
                    type inet:ipv6-prefix;
                    mandatory true;
                  }
                  leaf source-ipv6-prefix {
                    type inet:ipv6-prefix;
                    mandatory true;
                  }
                }
              }
            }
          }
        }
        case mpls-route {
          description

Wang, et al.             Expires October 5, 2015               [Page 23]
Internet-Draft                   RIB DM                       April 2015

            "Match on a MPLS label at the top of the MPLS label stack";
          leaf mpls-label {
            type uint32 ;
            mandatory true;
          }
        }
        case mac-route {
          description
            "Match on MAC destination addresses in the ethernet header";
          leaf mac-address {
            type uint32 ;
            mandatory true;
          }
        }
        case interface-route {
          description
            "Match on incoming interface of the packet";
          leaf interface-identifier {
            type if:interface-ref;
            mandatory true;
          }
        }
      }
    }
  }

  grouping route{
    description
      "The common attributes usesd for all routes";
    uses route-prefix;
    container nexthop{
      uses nexthop;
    }
    container route-statistic{
      leaf route-state {
        type route-state-def ;
        config false;
      }
      leaf route-installed-state {
        type route-installed-state-def ;
        config false;
      }
      leaf route-reason {
        type route-reason-def ;
        config false;
      }
    }
    container route-attributes{

Wang, et al.             Expires October 5, 2015               [Page 24]
Internet-Draft                   RIB DM                       April 2015

      uses route-attributes;
    }
    container route-vendor-attributes{
      uses route-vendor-attributes;
    }
  }

  grouping nexthop {
    leaf nexthop-id {
      mandatory true;
      type uint32;
    }
    choice nexthop-type {
      case nexthop-base {
        container nexthop-base {
          list nexthop-chain {
            key "nexthop-chain-id";
            uses nexthop-chain-member;
          }
        }
      }

       case nexthop-protection {
        list nexthop-protection-list {
            key "nexthop-protection-id";
            leaf nexthop-protection-id {
              mandatory true;
              type uint32;
            }
           leaf nexthop-preference {
             description
             "Nexthop-preference is used for protection schemes.
              It is an integer value between 1 and 99.  A lower
              value indicates higher preference.  To download a
              primary/standby/tertiary group to the FIB, the
              nexthops that are resolved and have two highest
              preferences are selected.";
             mandatory true;
             type nexthop-preference-def;
           }
           leaf nexthop {
             mandatory true;
             type nexthop-ref;
           }
        }
      }

      case nexthop-load-balance {

Wang, et al.             Expires October 5, 2015               [Page 25]
Internet-Draft                   RIB DM                       April 2015

        container nexthop-lb {
          list nexthop-lbs {
            key "nexthop-lbs-id";
            leaf nexthop-lbs-id {
              mandatory true;
              type uint32;
            }
            leaf nhop-lb-weight {
              mandatory true;
              type nhop-lb-weight-def;
            }
            leaf nexthop-lb-member {
              mandatory true;
              type nexthop-ref;
            }
          }
        }
      }

      case nexthop-replicate {
        container nexthop-replicate {
          list nexthop-replicates{
            key "nexthop-replicates-id";
            leaf nexthop-replicates-id {
              mandatory true;
              type uint32;
            }
            leaf nexthop-replicate {
              type nexthop-ref;
            }
          }
        }
      }
    }
  }

  grouping nexthop-chain-member {
    description
      "One nexthop content for a route.";
    leaf nexthop-chain-id{
      type uint32;
      mandatory true;
    }
    choice nexthop-chain-type {
      case nexthop-chain-member-special {
        container nexthop-chain-member-special {
          leaf nexthop-chain-member-special{
            type special-nexthop-def;

Wang, et al.             Expires October 5, 2015               [Page 26]
Internet-Draft                   RIB DM                       April 2015

          }
        }
      }

      case nexthop-chain-member-identifier{
        uses nexthop-chain-member-identifier;
      }

      case egress-interface-next-hop {
         description
           "Simple next-hop is specified as an outgoing interface,
            next-hop address or both.";
         leaf outgoing-interface {
           type if:interface-ref;
           mandatory true;
           description
             "Name of the outgoing interface.";
         }
      }

      case ipv4-address-next-hop {
        leaf next-hop-ipv4-address {
          type inet:ipv4-address;
          mandatory true;
          description
            "The nexthop is an IPv4 address.";
        }
      }

      case ipv6-address-next-hop {
        leaf next-hop-ipv6-address {
          type inet:ipv6-address;
          mandatory true;
          description
            "The nexthop is an IPv6 address.";
        }
      }

      case egress-interface-ipv4-next-hop {
        container next-hop-egress-interface-ipv4-address{
          leaf outgoing-interface {
            type if:interface-ref;
            mandatory true;
            description
              "Name of the outgoing interface.";
          }
          leaf next-hop-egress-ipv4-address {
            type inet:ipv4-address;

Wang, et al.             Expires October 5, 2015               [Page 27]
Internet-Draft                   RIB DM                       April 2015

            mandatory true;
            description
              "The nexthop points to an interface with
               an IPv4 address.";
          }
          description
            "Egress-interface and ip address: This can be usesd
             in cases e.g.where the ip address is a link-local
             address.";
        }
      }

      case egress-interface-ipv6-next-hop {
        container next-hop-egress-interface-ipv6-address{
          leaf outgoing-interface {
            type if:interface-ref;
            mandatory true;
            description
              "Name of the outgoing interface.";
          }
          leaf next-hop-egress-ipv6-address {
            type inet:ipv6-address;
            mandatory true;
            description
              "The nexthop points to an interface with
               an IPv6 address.";
          }
          description
            "Egress-interface and ip address: This can be usesd
             in cases e.g.where the ip address is a link-local
             address.";
        }
      }

      case egress-interface-mac-next-hop {
        container next-hop-egress-interface-mac-address{
          leaf outgoing-interface {
            type if:interface-ref;
            mandatory true;
            description
              "Name of the outgoing interface.";
          }
          leaf ieee-mac-address {
            type uint32;
            mandatory true;
            description
              "The nexthop points to an interface with
               a specific mac-address.";

Wang, et al.             Expires October 5, 2015               [Page 28]
Internet-Draft                   RIB DM                       April 2015

          }
          description
            "The egress interface must be an ethernet
             interface.Address resolution is not required
             for this nexthop."

        }
      }

      case tunnel-encap-next-hop {
        container tunnel-encap {
          uses tunnel-encap;
            leaf outgoing-interface {
              type string;
          }
          description
            "This can be an encap representing an ip tunnel or
             mpls tunnel or others as defined in this document.
             An optional egress interface can be specified to
             indicate which interface to send The packet out on.
             The egress interface is usesful when the network
             device contains eThernet interfaces and one needs
             to perform address resolution for The ip packet.";
        }
      }

      case logical-tunnel-next-hop {
        container logical-tunnel {
          uses logical-tunnel;
          description
            "This can be a MPLS LSP or a GRE tunnel (or others
             as defined in This document), that is represented
             by a unique identifier (e.g. name).";
        }
      }

      case rib-name {
        leaf rib-name {
          type string;
            description
              "A nexthop pointing to a rib indicates that the
               route lookup needs to continue in The specified
               rib.  This is a way to perform chained lookups.";
        }
      }
    }
  }

Wang, et al.             Expires October 5, 2015               [Page 29]
Internet-Draft                   RIB DM                       April 2015

  grouping nexthop-chain-member-identifier{
    choice nexthop-identifier-type{
      case nexthop-chain-name {
        leaf nexthop-chain-name {
          type string;
          mandatory true;
        }
      }
      case nexthop-chain-id {
        leaf nexthop-chain-id {
          type uint32;
          mandatory true;
        }
      }
    }
  }

  grouping route-vendor-attributes{
  }

  grouping logical-tunnel{
    leaf tunnel-type {
      type tunnel-type-def ;
      mandatory true;
    }
    leaf tunnel-name {
      type string ;
      mandatory true;
    }
  }

  grouping ipv4-header{
    leaf source-ipv4-address {
      type inet:ipv4-address;
      mandatory true;
    }
    leaf destination-ipv4-address {
      type inet:ipv4-address;
      mandatory true;
    }
    leaf protocol {
      type uint8;
      mandatory true;
    }
    leaf ttl {
      type uint8;
    }
    leaf dscp {

Wang, et al.             Expires October 5, 2015               [Page 30]
Internet-Draft                   RIB DM                       April 2015

      type uint8;
    }
  }

  grouping ipv6-header{
    leaf source-ipv6-address {
      type inet:ipv6-address;
      mandatory true;
    }
    leaf destination-ipv6-address {
      type inet:ipv6-address;
      mandatory true;
    }
    leaf next-header {
      type uint8;
      mandatory true;
    }
    leaf traffic-class {
      type uint8;
    }
    leaf flow-label {
      type uint16;
    }
    leaf hop-limit {
      type uint8;
    }
  }

  grouping nvgre-header{
    choice nvgre-type {
      description
        "nvgre-header.";
      case ipv4 {
        uses ipv4-header;
      }
      case ipv6 {
        uses ipv6-header;
      }
    }
    leaf virtual-subnet-id {
      type uint32;
      mandatory true;
    }
    leaf flow-id {
      type uint16;
    }
  }

Wang, et al.             Expires October 5, 2015               [Page 31]
Internet-Draft                   RIB DM                       April 2015

  grouping vxlan-header{
    choice vxlan-type {
      description
        "vxlan-header.";
      case ipv4 {
        uses ipv4-header;
      }
      case ipv6 {
        uses ipv6-header;
      }
    }
    leaf vxlan-identifier {
      type uint32;
    }
  }

  grouping gre-header{
    leaf gre-ip-destination {
      type inet:ipv4-address;
      mandatory true;
    }
    leaf gre-protocol-type {
      type inet:ipv4-address;
      mandatory true;
    }
    leaf gre-key {
      type uint64;
    }
  }

  grouping mpls-header{
    choice mpls-action-type {
      description
        "mpls-header.";
      case mpls-push {
        leaf mpls-push {
          type boolean;
          mandatory true;
        }
        leaf mpls-label {
          type uint32;
          mandatory true;
        }
        leaf s-bit {
          type boolean;
        }
        leaf tos-value {
          type uint8;

Wang, et al.             Expires October 5, 2015               [Page 32]
Internet-Draft                   RIB DM                       April 2015

        }
        leaf ttl-value {
          type uint8;
        }
          }
      case mpls-pop {
        leaf mpls-pop {
          type boolean;
          mandatory true;
        }
        leaf ttl-action {
          type uint8;
        }
      }
    }
  }

  grouping tunnel-encap{
    choice tunnel-type {
      description
        "options for next-hops.";
      case ipv4 {
        uses ipv4-header;
      }
      case ipv6 {
        uses ipv6-header;
      }
      case mpls {
        uses mpls-header;
      }
      case gre {
        uses gre-header;
      }
      case nvgre {
        uses nvgre-header;
      }
    }
  }

  grouping route-attributes{
    leaf route-preference {
      description
        "ROUTE_PREFERENCE: This is a numerical value that
         allows for comparing routes from different
         protocols.  Static configuration is also
         considered a protocol for the purpose of this
         field.  It iss also known as administrative-distance.
         The lower the value, the higher the preference.";

Wang, et al.             Expires October 5, 2015               [Page 33]
Internet-Draft                   RIB DM                       April 2015

        type uint32 ;
      mandatory true;
    }
    leaf local-only {
      type boolean ;
      mandatory true;
    }
    container address-family-route-attributes{
      choice route-type {
        case ip-route-attributes {
        }
        case mpls-route-attributes {
        }
        case ethernet-route-attributes {
        }
      }
    }
  }

  container routing-instance {
    description
      "Configuration of an 'i2rs' pseudo-protocol instance
       consists of a list of ribs.";

    leaf name {
      description
        "A routing instance is identified by its name,
        INSTANCE_name.  This MUST be unique across all routing
        instances in a given network device.";
      type string ;
      mandatory true;
    }
    list interface-list {
      description
        "This represents the list of interfaces associated
         with this routing instance.  The interface list helps
         constrain the boundaries of packet forwarding.
         Packets coming on these interfaces are directly
         associated with the given routing instance.  The
         interface list contains a list of identifiers, with
         each identifier uniquely identifying an interface.";
      key "name";
      leaf name {
        type if:interface-ref;
        description
         "A reference to the name of a configured network layer
         interface.";
      }

Wang, et al.             Expires October 5, 2015               [Page 34]
Internet-Draft                   RIB DM                       April 2015

    }
    uses rt:router-id ;
    list rib-list {
      description
        "This is the list of RIBs associated with this routing
         instance.  Each routing instance can have multiple RIBs
         to represent routes of different types.";
      key "name";
      leaf name {
        description
         "A reference to the name of a rib.";
       type string;
        mandatory true;
      }
      leaf rib-family {
        type rib-family-def;
        mandatory true;
      }
      leaf enable-ip-rpf-check {
        description
          "Each RIB can be optionally associated with a
           ENABLE_IP_RPF_CHECK attribute that enables Reverse
           path forwarding (RPF) checks on all IP routes in that
           RIB.  Reverse path forwarding (RPF) check is used to
           prevent spoofing and limit malicious traffic.";
        type boolean;
      }
      list route-list{
        key "route-index";
        uses route;
      }
    }
  }

  notification nexthop-resolution-status-change {
    description
        "Nexthop resolution status (resolved/unresolved)
         notification.";
    container nexthop{
      uses nexthop;
    }
    leaf nexthop-state {
      description
       "Nexthop resolution status (resolved/unresolved)
        notification.";
      type nexthop-state-def;
      mandatory true;
    }

Wang, et al.             Expires October 5, 2015               [Page 35]
Internet-Draft                   RIB DM                       April 2015

  }

  notification route-change {
    description
        "Route change notification.";
    leaf instance-name {
      description
        "A routing instance is identified by its name,
        INSTANCE_name.  This MUST be unique across all
        routing instances in a given network device.";
      type string ;
      mandatory true;
    }
    leaf rib-name {
      description
       "A reference to the name of a rib.";
      type string;
      mandatory true;
    }
    leaf rib-family {
      type rib-family-def;
      mandatory true;
    }
    uses route-prefix;
    leaf route-installed-state {
      description
       "Indicates whether the route got installed in the FIB.";
      type route-installed-state-def;
      mandatory true;
    }
    leaf route-state {
      description
       "Indicates whether a route is fully resolved and
        is a candidate for selection.";
      type route-state-def;
      mandatory true;
    }
    leaf route-reason {
      description
       "Need to be added.";
      type route-reason-def;
      mandatory true;
    }
  }
}
//   </code ends>

Wang, et al.             Expires October 5, 2015               [Page 36]
Internet-Draft                   RIB DM                       April 2015

4.  IANA Considerations

   TBD.

5.  Security Considerations

   This document introduces no new security threat and SHOULD follow the
   security requirements as stated in [I-D.ietf-i2rs-architecture].

6.  References

6.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

6.2.  Informative References

   [I-D.ietf-i2rs-architecture]
              Atlas, A., Halpern, J., Hares, S., Ward, D., and T.
              Nadeau, "An Architecture for the Interface to the Routing
              System", draft-ietf-i2rs-architecture-09 (work in
              progress), March 2015.

   [I-D.ietf-i2rs-rib-info-model]
              Bahadur, N., Folkes, R., Kini, S., and J. Medved, "Routing
              Information Base Info Model", draft-ietf-i2rs-rib-info-
              model-06 (work in progress), March 2015.

   [I-D.ietf-i2rs-usecase-reqs-summary]
              Hares, S. and M. Chen, "Summary of I2RS Use Case
              Requirements", draft-ietf-i2rs-usecase-reqs-summary-00
              (work in progress), November 2014.

   [RFC6020]  Bjorklund, M., "YANG - A Data Modeling Language for the
              Network Configuration Protocol (NETCONF)", RFC 6020,
              October 2010.

   [RFC6021]  Schoenwaelder, J., "Common YANG Data Types", RFC 6021,
              October 2010.

Authors' Addresses

   Lixing Wang
   Huawei

   Email: wang_little_star@sina.com

Wang, et al.             Expires October 5, 2015               [Page 37]
Internet-Draft                   RIB DM                       April 2015

   Hariharan Ananthakrishnan
   Packet Design

   Email: hari@packetdesign.com

   Mach(Guoyi) Chen
   Huawei

   Email: mach.chen@huawei.com

   Amit Dass
   Ericsson
   Torshamnsgatan 48.
   Stockholm  16480
   Sweden

   Email: amit.dass@ericsson.com

   Sriganesh Kini
   Ericsson

   Email: sriganesh.kini@ericsson.com

   Nitin Bahadur
   Bracket Computing

   Email: nitin_bahadur@yahoo.com

Wang, et al.             Expires October 5, 2015               [Page 38]