Filter-Based RIB Data Model

The Interface to the Routing System (I2RS) architecture provides dynamic read and write access to the information and state within the routing elements. The I2RS client interacts with the I2RS agent in one or more network routing systems. This document provides a yang module for the I2RS filter Based Routing Information Base (FB-RIB) and describes the I2RS interaction with routing filters within a routing element. The informational model for the FB-RIB is in

Filter-based routing is a technique used to make packet forwarding decisions based on a filter that is matched to the incoming packets and the specified action. It should be noted that that this is distinct from the static routes in the RIB where the routing is destination ddress based. A Filter-Based RIB (Routing Information Base) is contained in a routing instance (defined in ). It contains a list of filters (match-action conditions) and a list of interfaces the filter-based forwarding operates on, and default RIB(s). A Filter Based RIB uses packet forwarding policy. If packet reception is considered an event, then the I2RS Filter-based RIB uses a minimalistic Event-matchCondition-Action policy with the following characteristics: event = packet/frame received, match condition - match on field in frame/packet or circumstances relating to packet reception (e.g. time received), action - modify packet and forward/drop packet. A Filter-based RIB entry specifies match filters for the fields in a packet (which may include layer 1 to layer 3 header fields, transport or application fields) or size of the packet or interface received on. The matches are contained in an ordered list of filters which contain pairs of match condition-action (aka event-condition-action). If all matches fail, default action is to forward the packet using Destination Based forward from the default RIB(s). The default RIBs can be: created by the I2RS Routing Informational Base (RIB) manager using the yang model described in: in , or configured RIB created using static routes or . or static RIB created via static route yang model Actions in the condition-action pair may impact forwarding or set something in the packet that will impact forwarding. Policy actions are typically applied before applying QoS constraints since policy actions may override QoS constraint. The Filter-Based RIB resides in ephemeral state as does the I2RS RIB and I2RS topology models.

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 [RFC2119]. In this document, these words will appear with that interpretation only when in ALL CAPS. Lower case uses of these words are not to be interpreted as carrying RFC-2119 significance.

Command Line Interface Filter-Based Routing Information Base The policy rules in the filter-based RIB are prescriptive of the Event-Condition-Action form which is often represented by if Condition then action". Policy Groups are groups of policy rules. The groups of policy in the basic network policy allow grouping of policy by name. This structure allow easier management of customer-based or provider based filters, but does not change the policy-rules list. RIB Informational Model (RIB IM) A routing instance, in the context of the FB-FIB is a collection of RIBs, interfaces, and routing parameters. A routing instance creates a logical slice of the router and allows different logical slices; across a set of routers; to communicate with each other.

There are three levels in the Filter-Based RIB (FB-RIB) structure: a global FB-RIB structures, the common structure of the FB-RIB, and the groupings that make up the FB-RIB All structures have two types: configuration/ephemeral state and operational state. This yang model describes three types of FB-RIBS: configuration, I2RS, and BGP Flow Specification. The configuration FB-RIB yang module is config state ("config true" and "ephemeral false") and survives a reboot. The I2RS FB-RB yang model is reboot ephemeral ("config true" and "ephemeral true;"). The BGP Flow Specification Filter-Based RIB stores policy which is received by the BGP peers. The BGP configuration contains a flow-specification as part of its configuration, and the ability to export this flow specification to other BGP peers. The BGP local configuration with the flow specification is consider ("config true"), and it is possible to be ephemeral ("ephemeral true") or local configuration ("ephemeral false" ). The BGP flow specifications received from peers are derived state, just like other BGP dervised state.

Configuration RIBS +-----------------------------------------+ | routing instance | +-------|-------------|----------------|--+ | | | | | | +---------|----+ +-----|-----+ +--------|-----+ |config-fb-rib | |i2rs-fb-rib| |bgp-fs-fb-rib | | | | | |config only | +------|-------+ +-----|-----+ +------|-------+ |............:....|...............| : (uses common structures : in separate lists of FB-RIBs) +--------|----+ |fb-ribs* | | | +--|----------+ | Figure 3: Routing instance with three types of Filter-FIB lists The following section provides the high level yang structure diagrams for the following levels of structures for both config/ephemeral state and operationa. ietf-fb-rib - contains filter-based RIBS for config, I2RS FB-RIB, and BGP Flow Specification. fb-rib - that contains the structures for the filter-based grouping fb-rib-types - that contains the structures for groupings within the filter-based RIBS These structures are contained within the yang section in this draft. The packet-reception ECA policy yang module is contained in the draft . For those who desire more information regarding the logic behind the I2RS Filter-Based RIB, please see the Informational Model at: .

The Top-level Yang structure for a global FB-RIB types (similar to acl) is not defined for filter-based RIBS. The I2RS Filter-Based RIB should be defined under this structure under a routing instance. The three things under this RIB would be: configured Filter-Based RIB (aka Policy routing), I2RS reboot Ephemeral Filter-Based RIB, and BGP Flow Specification's Filter-Based RIB. All of these RIBs have similar actions. There are two types top-level structures for ietf-fb-ribs: config and operational state. The Top-level Yang structure for a global configuration of Filter-Based RIBs are:

Augments rt:logical-network-elements:\ :logical-network-element:network-instances: \ network-instance ietf-fb-rib module +--rw ietf-fb-rib +--rw default-instance-name string +--rw default-router-id rt:router-id +--rw config-fb-ribs if-feature "config-filter-based-RIB"; uses fb-ribs; +--rw i2rs-fb-ribs if-feature "I2RS-filter-based-RIB"; uses fb-rib-t:fb-ribs; +--rw bgp-fs-fb-ribs if-feature "BGP-FS-filter-based-RIB"; uses fb-rib-t:fb-ribs; Figure 5: configuration state The Top-level Yang structure for a global operational state of Filter-Based RIBs are:

Augments rt:logical-network-elements:\ :logical-network-element:network-instances: \ network-instance ietf-fb-rib module +--rw ietf-fb-rib-opstate +--rw default-instance-name string +--rw default-router-id rt:router-id +--rw config-fb-rib-opstate if-feature "config-filter-based-RIB"; uses fb-rib-t:fb-ribs-oper-status; +--rw i2rs-fb-rib-opstate { if-feature "I2RS-filter-based-RIB"; uses fb-rib-t:fb-ribs-oper-status; +--rw bgp-fs-fb-rib-opstate if-feature "BGP-FS-filter-based-RIB"; uses fb-rib-t:fb-ribs-oper-status; Figure 5: operational state

The Top-level yang structures at the Filter-Based RIB level have two types: configuration and operational state. The Top-level Yang structure for the FB-RIB types is:

HIgh Level Yang +--rw fb-ribs-oper-status +--rw fb-rib-oper-status* [fb-rib-name] uses pkt-eca:pkt-eca-opstate

<CODE BEGINS> file "ietf-fb-rib-types@2016-02-09.yang" module ietf-fb-rib-types { yang-version "1"; // namespace namespace "urn:ietf:params:xml:ns:yang:ietf-fb-rib-types"; prefix "fb-rib-t"; import ietf-interfaces {prefix "if";} import ietf-routing {prefix "rt";} import ietf-pkt-eca-policy {prefix "pkt-eca";} // meta organization "IETF"; contact "email: shares@ndzh.com; email: sriganesh.kini@ericsson.com email: cengiz@packetdesign.com email: ivandean@gmal.org email: linda.dunbar@huawei.com; email: russ@riw.com; "; description "This module describes a YANG model for the I2RS Filter-based RIB Types. These types specify types for the Filter-Based RIB. Copyright (c) 2015 IETF Trust and the persons identified as the document authors. All rights reserved. Redistribution and use in source and binary forms, with or without modification, is permitted pursuant to, and subject to the license terms contained in, the Simplified BSD License set forth in Section 4.c of the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info)."; revision "2016-02-09" { description "Filter-Based RIB protocol "; reference "draft-hares-i2rs-fb-rib-data-model-01"; } typedef fb-rib-type-def { type identityref { base "fb-rib-type"; } description "This type is used to refer to source of Filter-Based RIB: configuration, I2RS, Flow-Spec."; } identity fb-rib-type { description "This type is used to refer to source of Filter-Based RIB: configuration, I2RS, Flow-Spec."; } identity fb-rib-config-type { base fb-rib-type; description "config Filter-Based RIB"; } identity fb-rib-i2rs-ephemeral-type { base fb-rib-type; description "I2RS Reboot ephemeral Filter-Based RIB"; } identity fb-rib-BGP-FS-type { base fb-rib-type; description "BGP Flow Specification Filter-Based RIB"; } typedef fb-rib-policy-type-def { type identityref { base "fb-rib-policy-type"; } description "This type is used to refer to FB-RIB type"; } identity fb-rib-policy-type { description "Types of filter-based policies acl and eca"; } identity fb-rib-acl { base fb-rib-policy-type; description "filter based policy based on access-lists"; } identity fb-bnp-eca-rules { base fb-rib-policy-type; description "filter based policy based on qos forwarding rules"; } typedef fb-rules-status { type identityref { base "fb-rule-opstat"; } description "This type is used to refer to FB-RIB type"; } identity fb-rule-opstat { description "operational statues for filter rules inactive and active"; } identity fb-rule-inactive { base fb-rule-opstat; description "policy rule is inactive"; } identity fb-rule-active { base fb-rule-opstat; description "policy rule is active"; } grouping fb-rib-rule-order-status { leaf statement-order { type uint16; description "order identifier"; } leaf statement-oper_status { type fb-rules-status; description "status of rule"; } description "filter-rib policy rule order and status"; } grouping fb-rib-group-order-status { leaf group-refcnt { type uint16; description "refcnt for this group"; } leaf group-installed { type uint32; description "number of rules installed"; } leaf group-matches { type uint64; description "number of matches by all rules in group"; } description "fb-rib group list order and status info."; } grouping fb-rib-updates { leaf fb-rib-update-ref { type uint64; description "number of updates to this FB RIB since last reboot"; } description "FB-RIB update info"; } grouping default-fb-rib { // configuration instance for default RIB leaf config-instance { type string; description "instance name - string until netmod fixes mount issues"; } leaf config-rib { type string; description "name of config default RIB"; } //I2RS default instance for default RIB leaf i2rs-instance-name { type string; description "I2RS instance name"; } leaf i2rs-rib-name { type string; description "name of default I2RS RIB"; } leaf bgp-instance-name { type string; description "name of bgp instance"; } leaf bgp-fs-rib-name { type string; description "name of BGP flow specification default RIB"; } description "default RIB for forwarding if the policy match"; } grouping fb-ribs { list fb-rib { key fb-rib-name; leaf fb-rib-name { type string; mandatory true; description "RIB name"; } uses rt:address-family; leaf fb-type { type fb-rib-type-def; description "type of RIB list: config, I2RS rebooot ephemeral, BGP Flow Specification ephemeral. "; } list fb-rib-intf { key "name"; leaf name { type if:interface-ref; description "A reference to the name of a configured network layer interface."; } 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."; } uses default-fb-rib; // defaults ribs uses fb-rib-updates; // write refs to this RIB list instance-using { key instance-name; leaf instance-name { type string; description " name of instance using this fb-rib rt:routing-instance"; } description "instances using this fb-rib"; } // ordered rule list + group list uses pkt-eca:pkt-eca-policy-set; description "Configuration of an filter-based rib list"; } description "fb-rib group"; } grouping fb-ribs-oper-status { list fb-rib-oper-status { key fb-rib-name; leaf fb-rib-name { type string; description "rib name"; } uses pkt-eca:pkt-eca-opstate; description "Configuration of an filter-based rib list"; } description "list of FB-FIB operational status"; } } <CODE ENDS>

<CODE BEGINS> file "ietf-fb-rib@2016-02-09.yang" module ietf-fb-rib { yang-version "1"; // namespace namespace "urn:ietf:params:xml:ns:yang:ietf-fb-rib"; // replace with iana namespace when assigned prefix "fb-rib"; // import some basic inet types import ietf-yang-types {prefix "yang";} import ietf-fb-rib-types { prefix "fb-rib-t";} // meta organization "IETF"; contact "email: sriganesh.kini@ericsson.com email: cengiz@packetdesign.com email: anoop@ieee.duke.edu email: ivandean@gmail.org email: shares@ndzh.com; email: linda.dunbar@huawei.com; email: russ@riw.com; "; description "This Top level module describes a YANG model for the I2RS Filter-based RIB which is an global protocol independent FB RIB module."; revision "2016-02-09" { description "initial revision"; reference "draft-hares-i2rs-fb-rib-data-model-01"; } feature config-filter-based-RIB { description "This feature means that a node support config filter-based rib."; } feature I2RS-filter-based-RIB { description "This feature means that a node support I2RS filter-based rib."; } feature BGP-FS-filter-based-RIB { description "This feature means that a node support BGP FS filter-based rib."; } container ietf-fb-rib { presence "top-level structure for configuration"; leaf default-instance-name { type string; mandatory true; description "A routing instance is identified by its name, INSTANCE_name. This MUST be unique across all routing instances in a given network device."; } leaf default-router-id { type yang:dotted-quad; description "Default router id"; } container config-fb-rib { if-feature config-filter-based-RIB; uses fb-rib-t:fb-ribs; description "config filter-based RIB"; } container i2rs-fb-rib { if-feature I2RS-filter-based-RIB; uses fb-rib-t:fb-ribs; description "bgp-fs filter-based RIB"; } container bgp-fs-fb-rib { if-feature BGP-FS-filter-based-RIB; uses fb-rib-t:fb-ribs; description "bgp fs filter-based RIB"; } description "fb-rib augments routing instance"; } container ietf-fb-rib-opstate { presence "top-level structure for op-state"; config "false"; leaf default-instance-name { type string; mandatory true; description "A routing instance is identified by its name, INSTANCE_name. This MUST be unique across all routing instances in a given network device."; } leaf default-router-id { type yang:dotted-quad; description "Default router id"; } container config-fb-rib-opstate { if-feature config-filter-based-RIB; uses fb-rib-t:fb-ribs-oper-status; description "config filter-based RIB"; } container i2rs-fb-rib-opstate { if-feature I2RS-filter-based-RIB; uses fb-rib-t:fb-ribs-oper-status; description "bgp-fs filter-based RIB"; } container bgp-fs-fb-rib-opstate { if-feature BGP-FS-filter-based-RIB; uses fb-rib-t:fb-ribs-oper-status; description "bgp fs filter-based RIB"; } description "fb-rib augments routing instance"; } } <CODE ENDS>

TBD

A I2RS RIB is ephemeral data store that will dyanamically change traffic paths set by the routing configuration. An I2RS FB-RIB provides dynamic Event-Condition-Action policy that will further change the operation of forwarding by allow dyanmic policy and ephemeral RIBs to alter the traffic paths set by routing configuration. Care must be taken in deployments to use the appropriate security and operational control to make use of the tools the I2RS RIB and I2RS FB-RIB provide.