SFC Netmod R. Penno
Internet-Draft P. Quinn
Intended status: Standards Track Cisco Systems
Expires: September 3, 2015 D. Zhou
J. Li
Intel Corporation
March 02, 2015
Yang Data Model for Service Function Chaining
draft-penno-sfc-yang-13
Abstract
This document defines a YANG data model that can be used to configure
and manage Service Function Chains.
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 September 3, 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
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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 . . . . . . . . . . . . . . . . . . . . . . . . 3
2. Definitions and Acronyms . . . . . . . . . . . . . . . . . . 3
3. Understanding SFC Yang Models . . . . . . . . . . . . . . . . 3
4. Service Function (SF) . . . . . . . . . . . . . . . . . . . . 4
4.1. Module Structure . . . . . . . . . . . . . . . . . . . . 4
4.2. Service Function Configuration Module . . . . . . . . . . 6
5. Service Function Type (SFT) . . . . . . . . . . . . . . . . . 11
5.1. Module Structure . . . . . . . . . . . . . . . . . . . . 11
5.2. Service Function Type Configuration Model . . . . . . . . 11
6. Service Function Chain (SFC) . . . . . . . . . . . . . . . . 14
6.1. Module Structure . . . . . . . . . . . . . . . . . . . . 14
6.2. Service Function Chain Configuration Model . . . . . . . 15
7. Service Function Path (SFP) . . . . . . . . . . . . . . . . . 19
7.1. Module Structure . . . . . . . . . . . . . . . . . . . . 19
7.2. Service Function Path Configuration Model . . . . . . . . 20
8. Service Function Forwarder (SFF) . . . . . . . . . . . . . . 24
8.1. Module Struture . . . . . . . . . . . . . . . . . . . . . 24
8.2. Service Function Forwarder Model . . . . . . . . . . . . 25
9. Service Function Forwarder Open vSwitch (SFF-OVS) . . . . . . 30
9.1. Module Structure . . . . . . . . . . . . . . . . . . . . 30
9.2. Service Function Forwarder OVS Model . . . . . . . . . . 30
10. Service Locator (SL) . . . . . . . . . . . . . . . . . . . . 32
10.1. Module Structure . . . . . . . . . . . . . . . . . . . . 32
10.2. Service Locator Module . . . . . . . . . . . . . . . . . 32
11. Rendered Service Path (RSP) . . . . . . . . . . . . . . . . . 36
11.1. Module Structure . . . . . . . . . . . . . . . . . . . . 36
11.2. Rendered Service Path Module . . . . . . . . . . . . . . 37
12. Service Function Classifier (SCF) . . . . . . . . . . . . . . 43
12.1. Module Structure . . . . . . . . . . . . . . . . . . . . 43
12.2. Service Function Classifier Module . . . . . . . . . . . 44
13. Service Function Description Monitor Report (SF-DESC-MON-RPT) 47
13.1. Module Structure . . . . . . . . . . . . . . . . . . . . 47
13.2. Service Function Description Monitor Report Module . . . 48
14. Service Function Description Monitor (SF-DESC-MON) . . . . . 52
14.1. Module Structure . . . . . . . . . . . . . . . . . . . . 52
14.2. Service Function Description Monitor Report Module . . . 52
15. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 53
16. Security Considerations . . . . . . . . . . . . . . . . . . . 53
17. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 53
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18. Changes . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
19. References . . . . . . . . . . . . . . . . . . . . . . . . . 56
19.1. Normative References . . . . . . . . . . . . . . . . . . 56
19.2. Informative References . . . . . . . . . . . . . . . . . 57
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 57
1. Introduction
YANG [RFC6020] is a data definition language that was introduced to
define the contents of a conceptual data store that allows networked
devices to be managed using NETCONF [RFC6241]. YANG is proving
relevant beyond its initial confines, as bindings to other interfaces
(e.g. ReST) and encodings other than XML (e.g. JSON) are being
defined. Furthermore, YANG data models can be used as the basis of
implementation for other interfaces, such as CLI and programmatic
APIs.
This document defines a YANG data model that can be used to configure
and manage Service Function Chains
2. Definitions and Acronyms
The reader should be familiar with the terms contained in
[I-D.ietf-sfc-architecture], [I-D.ietf-sfc-problem-statement]
,[I-D.ietf-sfc-architecture] and [I-D.quinn-vxlan-gpe]
3. Understanding SFC Yang Models
There are two main models in SFC: service-function (SF) and service-
function-forwarder (SFF). Most other models are used or derived from
those models. SF describes a service function like firewall, napt44,
dpi, http-proxy, etc. SFF describes a forwarding element that moves
packets along a service path. A SFF to function only needs to be
able to associate a Service Path ID and SI to a next hop data plane
locator.
The service-locator model provides a centralized place to register
transport and endpoints used with SFFs and SFs. This allows reuse
across a large number of other models since in networking usually
data plane locators are widely used. Some examples of transport
types are GRE, VXLAN-GPE and the data plane locator are IP:port,
VLAN-ID and MPLS Label. This model is imported by SFF, SF and
Rendered Service Path (RSP) models.
Service Function Type model serves as a registry for SF types. The
model can be easily extended by anyone looking to define their own
service type. This model is imported by SF and Service Function
Chain (SFC). Since a SFC is an abstract order of service function
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types, having a registry of types is important. Furthermore, when we
instantiate a SFP and RSP from a SFC we need to choose the actual SFs
that will be traversed by the packets and this requires us to know
the type associated with a Service Function.
A service function path (SFP) is an intermediate step between SFC and
RSP. It allows the user to provide input or constraints into the
construction of a RSP. This input ranges from nothing to specifying
the entire path. During RSP construction, the controller examines
the SFP and 'fill in the blanks'.
One of the most important configuration aspects of a SF is the data
plane locators. A SF's data plane locators indicates how the SF can
be reached. A SF can have multiple data plane locators of different
transport and types as specified in the service locator model.
A SFF has also can have multiple data plane locators that indicate
how it can be reached. It is very important when constructing a RSP
to pick SFFs that have data plane locators of the same transport and
type so that the path works. A SFF has an additional very important
configuration container, the service function dictionary. The
service function dictionary stores the SFF's view of the Service
Functions. It contains all SFs and their data plane locators.
Therefore the Service Function data plane locators and the SFF
service function dictionary constitute two pieces of a puzzle. If
they fit, it means they can be used in a path, otherwise they can
not.
The RSP model is the result of creating a Service Function Chain,
applying policies through the Service Function Path and finally
choosing a collection of (SFF, SF) tuples that meet these criteria.
The RSP is an operational model, meaning it can read but not changed.
4. Service Function (SF)
This module describe a Service Function, which is an essential
building block of other modules.
4.1. Module Structure
module: service-function
+--rw service-functions
| +--rw service-function* [name]
| +--rw name string
| +--rw type sfc-sft:service-function-type
| +--rw rest-uri? inet:uri
| +--rw ip-mgmt-address? inet:ip-address
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| +--rw request_reclassification? boolean
| +--rw nsh-aware? boolean
| +--rw sf-data-plane-locator* [name]
| +--rw name string
| +--rw (locator-type)
| | +--:(ip)
| | | +--rw ip? inet:ip-address
| | | +--rw port? inet:port-number
| | +--:(lisp)
| | | +--rw eid? inet:ip-address
| | +--:(mac)
| | | +--rw mac? yang:mac-address
| | | +--rw vlan-id? uint16
| | +--:(function)
| | | +--rw function-name? string
| | +--:(mpls)
| | +--rw mpls-label? uint32
| +--rw transport? identityref
| +--rw service-function-forwarder? string
+--ro service-functions-state
+--ro service-function-state* [name]
+--ro name string
+--ro sf-service-path* [name]
+--ro name string
rpcs:
+---x delete-all-service-function
+---x put-service-function
| +--ro input
| +--ro name? string
| +--ro type sfc-sft:service-function-type
| +--ro rest-uri? inet:uri
| +--ro ip-mgmt-address? inet:ip-address
| +--ro request_reclassification? boolean
| +--ro nsh-aware? boolean
| +--ro sf-data-plane-locator* [name]
| +--ro name string
| +--ro (locator-type)
| | +--:(ip)
| | | +--ro ip? inet:ip-address
| | | +--ro port? inet:port-number
| | +--:(lisp)
| | | +--ro eid? inet:ip-address
| | +--:(mac)
| | | +--ro mac? yang:mac-address
| | | +--ro vlan-id? uint16
| | +--:(function)
| | | +--ro function-name? string
| | +--:(mpls)
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| | +--ro mpls-label? uint32
| +--ro transport? identityref
| +--ro service-function-forwarder? string
+---x read-service-function
| +--ro input
| | +--ro name string
| +--ro output
| +--ro name? string
| +--ro type sfc-sft:service-function-type
| +--ro rest-uri? inet:uri
| +--ro ip-mgmt-address? inet:ip-address
| +--ro request_reclassification? boolean
| +--ro nsh-aware? boolean
| +--ro sf-data-plane-locator* [name]
| +--ro name string
| +--ro (locator-type)
| | +--:(ip)
| | | +--ro ip? inet:ip-address
| | | +--ro port? inet:port-number
| | +--:(lisp)
| | | +--ro eid? inet:ip-address
| | +--:(mac)
| | | +--ro mac? yang:mac-address
| | | +--ro vlan-id? uint16
| | +--:(function)
| | | +--ro function-name? string
| | +--:(mpls)
| | +--ro mpls-label? uint32
| +--ro transport? identityref
| +--ro service-function-forwarder? string
+---x delete-service-function
+--ro input
+--ro name string
4.2. Service Function Configuration Module
file "service-function@2014-07-01.yang"
module service-function {
namespace "urn:cisco:params:xml:ns:yang:sfc-sf";
prefix sfc-sf;
import ietf-inet-types { prefix inet; }
import ietf-yang-types { prefix yang; }
import service-function-type {prefix sfc-sft;}
import service-locator {prefix sfc-sl;}
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organization "Cisco Systems, Inc.";
contact "Reinaldo Penno ";
description
"This module contains a collection of YANG definitions for
managing service function.
It follows closely the constructs of
http://tools.ietf.org/html/draft-ietf-netmod-interfaces-cfg-12
Copyright (c) 2013 IETF Trust and the persons identified as
authors of the code. 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).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
// RFC Ed.: replace XXXX with actual RFC number and remove this
// note.
// RFC Ed.: update the date below with the date of RFC publication
// and remove this note.
revision 2014-07-01 {
description
"Changes based on Opendaylight Testing.";
}
typedef service-function-ref {
type leafref {
path "/sfc-sf:service-functions/sfc-sf:service-function/"
+ "sfc-sf:name";
}
description
"This type is used by data models that need to reference
configured service functions.";
}
grouping service-function-entry {
description
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"This group bundles together all information related to a
single service function";
leaf name {
type string;
description
"The name of the service function.";
}
leaf type {
type sfc-sft:service-function-type;
mandatory true;
description
"Service Function Type from service-function-type yang
model";
}
leaf rest-uri {
description "URI of REST based management";
type inet:uri;
}
leaf ip-mgmt-address {
type inet:ip-address;
description
"The IP and port used to configure this service-function";
}
leaf request_reclassification {
description "This leaf determines whether SF can request
reclassification by the SFF";
type boolean;
}
leaf nsh-aware {
type boolean;
description "Whether this SF can process NSH headers";
}
list sf-data-plane-locator {
description
"A network data-plane locator";
key "name";
leaf name {
type string;
description
"A unique string that represents this
data-plane-locator";
}
uses sfc-sl:data-plane-locator;
leaf service-function-forwarder {
type string;
description
"The service function forwarder associated with this
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locator";
}
}
}
container service-functions {
description
"A function that is responsible for specific
treatment of received packets. A Service Function can act at
various layers of a protocol stack (e.g., at the network layer
or other OSI layers). A Service Function can be a virtual
element or be embedded in a physical network element. One of
multiple Service Functions can be embedded in the same network
element. Multiple occurrences of the Service Function can be
enabled in the same administrative domain.
One or more Service Functions can be involved in the delivery
of added-value services. A non-exhaustive list of Service
Functions includes: firewalls, WAN and application
acceleration, Deep Packet Inspection (DPI),a LI (Lawful
Intercept) module, server load balancers, NAT44 [RFC3022],
NAT64 [RFC6146], NPTv6 [RFC6296], HOST_ID injection, HTTP
Header Enrichment functions, TCP optimizer, etc.
An SF may be SFC encapsulation aware, that is it receives, and
acts on information in the SFC encapsulation, or unaware in
which case data forwarded to the service does not contain the
SFC encapsulation.";
list service-function {
description
"This list holds configuration data for all service functions
in the domain";
key "name";
uses service-function-entry;
}
}
container service-functions-state {
description
"This container hold operational state for all service
functions";
config false;
list service-function-state {
description
"This list holds operational data for all service functions
in the domain";
key "name";
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leaf name {
type string;
description
"the name of the service function";
}
list sf-service-path {
key "name";
leaf name {
type string;
description
"The name of the Service Path";
}
description
"A list of all service function paths that contain this
service function";
}
}
}
rpc delete-all-service-function {
description
"Deletes all service functions";
}
rpc put-service-function {
description
"Creates a service function";
input {
uses service-function-entry;
}
}
rpc read-service-function {
description
"Reads a service function";
input {
leaf name {
type string;
mandatory true;
description "The name of the service function.";
}
}
output {
uses service-function-entry;
}
}
rpc delete-service-function {
description
"Deletes a service function";
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input {
leaf name {
type string;
mandatory true;
description "The name of the service function.";
}
}
}
}
5. Service Function Type (SFT)
This module holds one list for each service function type found in
the system. Each one of these lists has the name of all service
functions configured on the system of that particular type. This
allows finding a service function of a given type simple.
5.1. Module Structure
module: service-function-type
+--rw service-function-types
+--rw service-function-type* [type]
+--rw type service-function-type
+--rw sft-service-function-name* [name]
+--rw name string
5.2. Service Function Type Configuration Model
file "service-function-type@2014-07-01.yang"
module service-function-type {
namespace "urn:cisco:params:xml:ns:yang:sfc-sft";
prefix sfc-sft;
import ietf-inet-types { prefix inet; }
import ietf-yang-types { prefix yang; }
organization "Cisco Systems, Inc.";
contact "Reinaldo Penno ";
description
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"This module contains a collection of YANG definitions for
managing service function types.
It follows closely the constructs of
http://tools.ietf.org/html/draft-ietf-netmod-interfaces-cfg-12
Copyright (c) 2013 IETF Trust and the persons identified as
authors of the code. 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).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
// RFC Ed.: replace XXXX with actual RFC number and remove this
// note.
// RFC Ed.: update the date below with the date of RFC publication
// and remove this note.
revision 2014-07-01 {
description
"Changes based on Opendaylight Testing.";
}
// Service Function
// Service Function Type definitions
identity service-function-type-identity {
description
"Base identity from which specific service function
types are derived.";
}
identity firewall {
base "service-function-type-identity";
description "Firewall";
}
identity dpi {
base "service-function-type-identity";
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description "Deep Packet Inspection";
}
identity napt44 {
base "service-function-type-identity";
description "Network Address and Port Translation 44";
}
identity qos {
base "service-function-type-identity";
description "Quality of Service";
}
identity ids {
base "service-function-type-identity";
description "Intrusion Detection System";
}
identity http-header-enrichment {
base "service-function-type-identity";
description "HTTP services that add HTTP headers for charging and adding subscriber metadata";
}
typedef service-function-type {
type identityref {
base "service-function-type-identity";
}
description "This type is used to reference all
registered service function types";
}
container service-function-types {
description
"A list of Service function Types. For each type we keep
a list of Service Functions";
list service-function-type {
key "type";
leaf type {
type service-function-type;
description
"The service function type";
}
list sft-service-function-name {
key "name";
leaf name {
type string;
description
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"The name of the service function.";
}
description
"The list of all service functions of a specific type";
}
description
"A list of all service types. Each service-type entry holds
a list of all service functions of the type";
}
}
}
6. Service Function Chain (SFC)
This model describes a service function chain which is basically an
ordered list of services. But a service function chain does not
specify exactly which service (firewal1 vs. firewall2) will be used
to actually process packets.
6.1. Module Structure
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module: service-function-chain
+--rw service-function-chains
| +--rw service-function-chain* [name]
| +--rw name string
| +--rw symmetric? boolean
| +--rw sfc-service-function* [name]
| +--rw name string
| +--rw type sfc-sft:service-function-type
| +--rw order? uint8
+--ro service-function-chains-state
+--ro service-function-chain-state* [name]
+--ro name string
+--ro sfc-service-function-path* string
rpcs:
+---x instantiate-service-function-chain
| +--ro input
| | +--ro name string
| +--ro output
| +--ro name? string
+---x put-service-function-chains
+--ro input
+--ro service-function-chain* [name]
+--ro name string
+--ro symmetric? boolean
+--ro sfc-service-function* [name]
+--ro name string
+--ro type sfc-sft:service-function-type
+--ro order? uint8
6.2. Service Function Chain Configuration Model
file "service-function-chain@2014-07-01.yang"
module service-function-chain {
namespace "urn:cisco:params:xml:ns:yang:sfc-sfc";
prefix sfc-sfc;
import ietf-inet-types { prefix inet; }
import ietf-yang-types { prefix yang; }
import service-function {prefix sfc-sf; }
import service-function-type {prefix sfc-sft;}
organization "Cisco Systems, Inc.";
contact "Reinaldo Penno ";
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description
"This module contains a collection of YANG definitions for
managing service function chains.
Copyright (c) 2013 IETF Trust and the persons identified as
authors of the code. 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).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
// RFC Ed.: replace XXXX with actual RFC number and remove this
// note.
// RFC Ed.: update the date below with the date of RFC publication
// and remove this note.
revision 2014-07-01 {
description
"Revised based on Opendaylight Project feedback";
}
grouping service-function-chain-grouping {
list service-function-chain {
description
"A list that holds all service function chains in the
domain";
key "name";
leaf name {
type string;
description
"the name of the service function chain";
}
leaf symmetric {
type boolean;
default false;
description
"If the chain is symmetric we will create two service
paths, one ingress and another egress. Packets traverse
the egress service path in the reverse order of the
ingress path";
}
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list sfc-service-function {
key "name";
leaf name {
type string;
description
"A unique handle that describes the service function
that will be chosen for this type, such as
ingress-dpi. This is not the service function name";
}
leaf type {
type sfc-sft:service-function-type;
mandatory true;
description
"Service Function Type from service-function-type.yang";
}
leaf order {
type uint8;
}
ordered-by user;
description
"A list of service functions that compose the service
chain";
}
}
description
"This group bundles together all service function chains in the
domain";
}
// Service Function Chains
container service-function-chains {
uses service-function-chain-grouping;
description
"A service Function chain defines an
abstract set of service functions and their ordering
constraints that must be applied to packets and/or frames
selected as a result of classification. The implied order
may not be a linear progression as the architecture allows
for nodes that copy to more than one branch, and also allows
for cases where there is flexibility in the order in which
services need to be applied. The term service chain is often
used as shorthand for service function chain.";
}
container service-function-chains-state {
config false;
list service-function-chain-state {
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description
"A list that contains operational service function
chain state";
key "name";
leaf name {
type string;
description
"the name of the service function chain";
}
leaf-list sfc-service-function-path {
type string;
description
"A list of all service function paths instantiated from
this chain";
}
}
description
"This containers holds operational service function
chain state and their associated service path";
}
// Remote procedure calls
// (main feature: instantiation of a SFC)
rpc instantiate-service-function-chain {
description
"Instantiates a single service function";
input {
leaf name {
type string;
mandatory true;
description
"The name of the service function chain to be
instantiated.";
}
}
output {
leaf name {
type string;
description
"The name of the created service function path.";
}
}
}
// (RPC for testing)
rpc put-service-function-chains {
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description
"Creates Service-Functions";
input {
uses service-function-chain-grouping;
}
}
}
7. Service Function Path (SFP)
A Service Function Path is an instantiation of a service function
chain. It allows be user to provide constrains for the rendering of
the service path such as specific service-hops that need to be
visited, the transport encapsulation used in the overlay, whether
paths should be symmetric, amongst others.
7.1. Module Structure
module: service-function-path
+--rw service-function-paths
| +--rw service-function-path* [name]
| +--rw name string
| +--rw symmetric? boolean
| +--rw classifier? string
| +--rw symmetric-classifier? string
| +--rw context-metadata? sfc-md:context-metadata-ref
| +--rw variable-metadata? sfc-md:variable-metadata-ref
| +--rw service-path-hop* [hop-number]
| | +--rw hop-number uint8
| | +--rw service-function-name? string
| | +--rw service-function-forwarder? string
| | +--rw service-index? uint8
| +--rw service-chain-name string
| +--rw starting-index? uint8
| +--rw path-id? uint32
+--ro service-function-paths-state
+--ro service-function-path-state* [name]
+--ro name string
+--ro sfp-rendered-service-path* [name]
+--ro name string
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7.2. Service Function Path Configuration Model
file "service-function-path@2014-07-01.yang"
module service-function-path {
namespace "urn:cisco:params:xml:ns:yang:sfc-sfp";
prefix sfc-sfp;
import ietf-inet-types { prefix inet; }
import ietf-yang-types { prefix yang; }
import service-function {prefix sfc-sf; }
import service-function-metadata {prefix sfc-md; }
organization "Cisco Systems, Inc.";
contact "Reinaldo Penno ";
description
"This module contains a collection of YANG definitions for
managing service function chains.
Copyright (c) 2013 IETF Trust and the persons identified as
authors of the code. 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).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
// RFC Ed.: replace XXXX with actual RFC number and remove this
// note.
// RFC Ed.: update the date below with the date of RFC publication
// and remove this note.
revision 2014-07-01 {
description
"Changes based on Opendaylight Testing and IETF SFC ml.";
}
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typedef service-function-path-ref {
type leafref {
path "/sfc-sfp:service-function-paths/" +
"sfc-sfp:service-function-path/sfc-sfp:name";
}
description
"This type is used by data models that need to reference
configured service functions.";
}
// Service Function Path
container service-function-paths {
description
"The SFP provides a level of indirection
between the fully abstract notion of service chain as an
abstract sequence of functions to be delivered, and the
fully specified notion of exactly what SFF/SFs the packet
will visit when it actually traverses the network. By
allowing the control components to specify the use of this
level of indirection, the deployment may choose the degree
of SFF/SF selection authority that is delegated to the
network";
list service-function-path {
description
"A list that holds configuration data for all SFPs in the
domain";
key "name";
leaf name {
type string;
description
"The name of this service function path";
}
leaf symmetric {
type boolean;
default false;
description
"If the chain is symmetric we will create two service
paths, one ingress and another egress. Packets traverse
the egress service path in the reverse order of the
ingress path";
}
leaf classifier {
type string;
description "The classifier responsible for directing"
+ "packets to this service path";
}
leaf symmetric-classifier {
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type string;
description "The classifier responsible for directing"
+ "packets to this service path";
}
leaf context-metadata {
type sfc-md:context-metadata-ref;
description
"The name of the associated context metadata";
}
leaf variable-metadata {
type sfc-md:variable-metadata-ref;
description
"The name of the associated variable metadata";
}
list service-path-hop {
key "hop-number";
leaf hop-number {
type uint8;
description
"A Monotonically increasing number";
}
leaf service-function-name {
type string;
description
"Service Function name";
}
leaf service-function-forwarder {
type string;
description
"Service Function Forwarder name";
}
leaf service-index {
type uint8;
description
"Provides location within the service path.
Service index MUST be decremented by service functions
or proxy nodes after performing required services. MAY
be used in conjunction with service path for path
selection. Service Index is also valuable when
troubleshooting/reporting service paths. In addition to
location within a path, SI can be used for loop
detection.";
}
ordered-by user;
description
"A list of service functions that compose the
service path";
}
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leaf service-chain-name {
type string;
mandatory true;
description
"The Service Function Chain used as blueprint for this
path";
}
leaf starting-index {
type uint8;
description
"Starting service index";
}
leaf path-id {
type uint32 {
range "0..16777216";
}
description
"Identifies a service path.
Participating nodes MUST use this identifier for path
selection. An administrator can use the service path
value for reporting and troubleshooting packets along
a specific path.";
}
}
}
container service-function-paths-state {
description
"This container hold operational state for all service
function paths";
config false;
list service-function-path-state {
description
"This list holds operational data for all service function
paths in the domain";
key "name";
leaf name {
type string;
description
"The name of the service function path";
}
list sfp-rendered-service-path {
key "name";
leaf name {
type string;
description
"The name of the Rendered Service Path";
}
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description
"A list of all rendered service paths instantiated
from this service path";
}
}
}
}
8. Service Function Forwarder (SFF)
This module describes the configuration a SFF needs to have in order
to route packets to the service functions it serves. the SFF needs to
have a table with service function name and associated locator. The
locator could be an IP address and port, an internal function call or
some other unique identifier.
8.1. Module Struture
module: service-function-forwarder
+--rw service-function-forwarders
| +--rw service-function-forwarder* [name]
| +--rw name string
| +--rw service-node? string
| +--rw ip-mgmt-address? inet:ip-address
| +--rw rest-uri? inet:uri
| +--rw sff-data-plane-locator* [name]
| | +--rw name string
| | +--rw data-plane-locator
| | +--rw (locator-type)
| | | +--:(ip)
| | | | +--rw ip? inet:ip-address
| | | | +--rw port? inet:port-number
| | | +--:(lisp)
| | | | +--rw eid? inet:ip-address
| | | +--:(mac)
| | | | +--rw mac? yang:mac-address
| | | | +--rw vlan-id? uint16
| | | +--:(function)
| | | | +--rw function-name? string
| | | +--:(mpls)
| | | +--rw mpls-label? uint32
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| | +--rw transport? identityref
| +--rw service-function-dictionary* [name]
| +--rw name string
| +--rw type? sfc-sft:service-function-type
| +--rw sff-sf-data-plane-locator
| | +--rw (locator-type)
| | | +--:(ip)
| | | | +--rw ip? inet:ip-address
| | | | +--rw port? inet:port-number
| | | +--:(lisp)
| | | | +--rw eid? inet:ip-address
| | | +--:(mac)
| | | | +--rw mac? yang:mac-address
| | | | +--rw vlan-id? uint16
| | | +--:(function)
| | | | +--rw function-name? string
| | | +--:(mpls)
| | | +--rw mpls-label? uint32
| | +--rw transport? identityref
| +--rw sff-interfaces* [sff-interface]
| | +--rw sff-interface string
| +--rw failmode? failmode-type
+--ro service-function-forwarders-state
+--ro service-function-forwarder-state* [name]
+--ro name string
+--ro sff-service-path* [name]
+--ro name string
8.2. Service Function Forwarder Model
file "service-function-forwarder@2014-07-01.yang"
module service-function-forwarder {
namespace "urn:cisco:params:xml:ns:yang:sfc-sff";
prefix sfc-sff;
import ietf-inet-types { prefix inet;}
import ietf-yang-types {
prefix "yang";
revision-date 2013-07-15;
}
import service-locator { prefix sfc-sl; }
import service-function-type {prefix sfc-sft;}
organization "Cisco Systems, Inc.";
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contact "Reinaldo Penno ";
description
"This module contains a collection of YANG definitions for
managing service function forwarders.
Copyright (c) 2013 IETF Trust and the persons identified as
authors of the code. 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).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
// RFC Ed.: replace XXXX with actual RFC number and remove this
// note.
// RFC Ed.: update the date below with the date of RFC publication
// and remove this note.
revision 2014-07-01 {
description
"Revision based on Opendaylight project feedback";
}
// Failmode type definitions
identity failmode-type-identity {
description
"Base identity from which specific failmode
types are derived. Fail mode specifies the behavior
when the interface does not have connectivity to the
service node.";
}
typedef failmode-type {
type identityref {
base "failmode-type-identity";
}
description "This type is used to reference all
registered failmode types";
}
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identity close {
base "failmode-type-identity";
description "When service-function can not reach service
function, packets will be dropped";
}
identity open {
base "failmode-type-identity";
description "When service-function can not reach service
function, packets will be forwarded";
}
container service-function-forwarders {
description
"A service function forwarder is
responsible for delivering traffic received from the SFC
network forwarder to one or more connected service
functions via information carried in the SFC encapsulation.
";
list service-function-forwarder {
description
"A list that holds configuration of all SFFs in the domain";
key "name";
leaf name {
type string;
description
"The unique name of this service function forwarder, such
as SFF1";
}
leaf service-node {
type string;
description "The service node that hosts this SFF";
}
leaf ip-mgmt-address {
type inet:ip-address;
description
"The IP and port used to configure this service-function-forwarder";
}
leaf rest-uri {
description "URI of REST based management";
type inet:uri;
}
list sff-data-plane-locator {
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description
"A list of all data-plane-locators of this SFF.";
key "name";
leaf name {
type string;
description
"A unique string that represents this data-plane-locator";
}
container data-plane-locator {
description
"This container holds configuration for the overlay data plane"
+ "locator used by this SFF. This could be VXLAN, GRE, etc";
uses sfc-sl:data-plane-locator;
}
}
list service-function-dictionary {
key "name";
leaf name {
type string;
description
"The name of the service function.";
}
leaf type {
type sfc-sft:service-function-type;
description
"Service Function Type from service-function-type yang
model";
}
container sff-sf-data-plane-locator {
description
"The SFF uses this data plane locator when sending packets to the"
+ "associated service function";
uses sfc-sl:data-plane-locator;
}
list sff-interfaces {
key "sff-interface";
leaf sff-interface {
type string;
description
"An individual interface on the SFF connected to the
SF";
}
description
"A list of interfaces on the SFF which are connected to this SF,"
+ "usually one 1 or 2 elements";
}
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leaf failmode {
type failmode-type;
description
"This leaf defines what should the SFF do if it can not
send packets to the SF";
}
description
"A list of all Service Functions attached to this SFF.";
}
}
}
container service-function-forwarders-state {
description
"This container hold operational state for all service
function forwarders";
config false;
list service-function-forwarder-state {
description
"This list holds operational data for all service functions
forwarders in the domain";
key "name";
leaf name {
type string;
description
"the name of the service function forwarder";
}
list sff-service-path {
key "name";
leaf name {
type string;
description
"The name of the Service Path";
}
description
"A list of all service function paths that contain this
service function forwarder";
}
}
}
}
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9. Service Function Forwarder Open vSwitch (SFF-OVS)
This module augments the SFF model for Open vSwitch, meaning when
Open vSwitche (OVS) bridges are used as SFF.
9.1. Module Structure
module: service-function-forwarder-ovs
augment /sfc-sff:service-function-forwarders/sfc-sff:service-function-forwarder/sfc-sff:sff-data-plane-locator:
+--rw ovs-bridge
+--rw bridge-name? string
+--rw uuid? yang:uuid
+--rw external-ids* [name]
| +--rw name string
| +--rw value? string
+--rw rest-uri? inet:uri
augment /sfc-sff:service-function-forwarders/sfc-sff:service-function-forwarder/sfc-sff:service-function-dictionary/sfc-sff:sff-sf-data-plane-locator:
+--rw ovs-bridge
+--rw bridge-name? string
+--rw uuid? yang:uuid
+--rw external-ids* [name]
| +--rw name string
| +--rw value? string
+--rw rest-uri? inet:uri
9.2. Service Function Forwarder OVS Model
file "service-function-forwarder-ovs@2014-07-01.yang"
module service-function-forwarder-ovs {
yang-version 1;
namespace "urn:cisco:params:xml:ns:yang:sfc-sff-ovs";
prefix sfc-sff-ovs;
import service-function-forwarder {
prefix "sfc-sff";
}
import ietf-inet-types {
prefix "inet";
}
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import ietf-yang-types {
prefix "yang";
revision-date 2013-07-15;
}
organization "Cisco Systems, Inc.";
contact "Reinaldo Penno ";
revision 2014-07-01 {
description "Augmentation of SFF for OVS";
}
grouping bridge {
container ovs-bridge {
leaf bridge-name {
description "Open vSwitch bridge name. In Openstack it is usually"
+ "br-tun or br-int depending if it is used in the overlay or"
+ "facing virtual machines respectively";
type string;
}
leaf uuid {
description "Open vSwitch bridge UUID";
type yang:uuid;
}
list external-ids {
description
"The list of external ids associated with this
bridge";
key "name";
leaf name {
type string;
description
"A unique string that represents this external-id such
as attached-mac";
}
leaf value {
type string;
description
"A unique string that represents the value of the
external-id such as fa:16:3e:56:47:10";
}
}
}
}
augment "/sfc-sff:service-function-forwarders/"
+ "sfc-sff:service-function-forwarder/"
+ "sfc-sff:sff-data-plane-locator" {
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uses bridge;
}
augment "/sfc-sff:service-function-forwarders/"
+ "sfc-sff:service-function-forwarder/"
+ "sfc-sff:service-function-dictionary/"
+ "sfc-sff:sff-sf-data-plane-locator" {
uses bridge;
}
}
10. Service Locator (SL)
This module provides a single point of registration for all network
locators types used in Services Function Chaining. the model can be
augmented at will with locators appropriate for each use-case.
10.1. Module Structure
10.2. Service Locator Module
file "service-locator@2014-07-01.yang"
module service-locator {
namespace "urn:cisco:params:xml:ns:yang:sfc-sl";
prefix sfc-sl;
import ietf-inet-types { prefix inet; }
import ietf-yang-types { prefix yang; }
organization "Cisco Systems, Inc.";
contact "Reinaldo Penno ";
description
"This module contains a collection of YANG definitions for
managing service locators. Service locators are used as
data plane network destinations for Service Functions and
Service Function Forwarders
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It follows closely the constructs of
http://tools.ietf.org/html/draft-ietf-netmod-interfaces-cfg-12
Copyright (c) 2013 IETF Trust and the persons identified as
authors of the code. 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).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
// RFC Ed.: replace XXXX with actual RFC number and remove this
// note.
// RFC Ed.: update the date below with the date of RFC publication
// and remove this note.
revision 2014-07-01 {
description
"Changes based on Opendaylight Testing.";
}
// Locator definitions
// Transport type definitions
identity transport-type {
description
"Base identity from which specific transport types are
derived.";
}
identity vxlan-gpe {
base "sl-transport-type";
description "Programmable vxlan transport type";
}
identity gre {
base "sl-transport-type";
description "GRE transport type";
}
identity mpls {
base "sl-transport-type";
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description "Multi Protocol Label Switching transport type";
}
identity other {
base "sl-transport-type";
description "unspecified transport type";
}
identity sl-transport-type {
base "transport-type";
description
"This identity is used as a base for all transport
types";
}
grouping lisp-locator {
description
"Data plane-locator: Lisp Eid(IP)";
leaf eid {
type inet:ip-address;
description "Data-plane IP address";
}
}
grouping ip-port-locator {
description
"Data plane-locator: IP address and L4 port";
leaf ip {
type inet:ip-address;
description "Data-plane IP address";
}
leaf port {
type inet:port-number;
description "Data-plane port number";
}
}
grouping mac-address-locator {
description
"Data plane-locator: mac address and optional vlan-id";
leaf mac {
type yang:mac-address;
description "Data-plane MAC address";
}
leaf vlan-id {
type uint16 {
range "1..4094";
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}
description "Data-plane VLAN ID address";
}
}
grouping mpls-locator {
description
"Data plane-locator: MPLS";
leaf mpls-label {
type uint32 {
range "1..1048575";
}
description "MPLS Label, 20 bits";
}
}
grouping function-locator {
description
"When SF is co-located with SFF, this could be the name of a
function or method.";
leaf function-name {
type string;
description "Function or method name";
}
}
grouping data-plane-locator {
description
"This group presents data-plane locator
information for service function elements in the domain";
choice locator-type {
mandatory true;
case ip {
uses ip-port-locator;
}
case lisp {
uses lisp-locator;
}
case mac {
uses mac-address-locator;
}
case function {
uses function-locator;
}
case mpls {
uses mpls-locator;
}
description "The collection of all possible data-plane
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locators. Only one can be chosen";
}
leaf transport {
type identityref {
base sfc-sl:sl-transport-type;
}
}
}
}
11. Rendered Service Path (RSP)
This module holds the actual service-hops a packet will traverse when
forwarded through a specific service path.
11.1. Module Structure
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module: rendered-service-path
+--ro rendered-service-paths
+--ro rendered-service-path* [name]
+--ro name string
+--ro parent-service-function-path? string
+--ro context-metadata? sfc-md:context-metadata-ref
+--ro variable-metadata? sfc-md:variable-metadata-ref
+--ro rendered-service-path-hop* [hop-number]
| +--ro hop-number uint8
| +--ro service-function-name? string
| +--ro service-function-forwarder? string
| +--ro service-index? uint8
+--ro service-chain-name string
+--ro starting-index? uint8
+--ro path-id? uint32
rpcs:
+---x delete-rendered-path
| +--ro input
| | +--ro name? string
| +--ro output
| +--ro result? boolean
+---x create-rendered-path
+--ro input
| +--ro name? string
| +--ro parent-service-function-path? string
| +--ro symmetric? boolean
| +--ro classifier? string
| +--ro symmetric-classifier? string
+--ro output
+--ro result? boolean
11.2. Rendered Service Path Module
file "rendered-service-path.yang"
module rendered-service-path {
namespace "urn:cisco:params:xml:ns:yang:sfc-rsp";
prefix sfc-rsp;
import ietf-inet-types { prefix inet; }
import ietf-yang-types { prefix yang; }
import service-function {prefix sfc-sf; }
import service-function-metadata {prefix sfc-md; }
import service-function-forwarder {prefix sfc-sff; }
import service-locator {prefix sfc-sl;}
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organization "Cisco Systems, Inc.";
contact "Reinaldo Penno ";
description
"This module contains a collection of YANG definitions to
manage Rendered Service Paths.
Copyright (c) 2013 IETF Trust and the persons identified as
authors of the code. 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).
This version of this YANG module is part of RFC XXXX; see
the RFC itself for full legal notices.";
// RFC Ed.: replace XXXX with actual RFC number and remove this
// note.
// RFC Ed.: update the date below with the date of RFC publication
// and remove this note.
revision 2014-07-01 {
description
"Changes based on Opendaylight Testing and IETF SFC ml.";
}
typedef rendered-service-path-ref {
type leafref {
path "/sfc-rsp:service-function-paths/" +
"sfc-rsp:rendered-service-path/sfc-rsp:name";
}
description
"This type is used by data models that need to reference
rendered service paths.";
}
// Rendered Service Path
container rendered-service-paths {
config false;
description
"The SFP provides a level of indirection
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between the fully abstract notion of service chain as an
abstract sequence of functions to be delivered, and the
fully specified notion of exactly what SFF/SFs the packet
will visit when it actually traverses the network. By
allowing the control components to specify the use of this
level of indirection, the deployment may choose the degree
of SFF/SF selection authority that is delegated to the
network";
list rendered-service-path {
description
"A list that holds operational data for all RSPs in the
domain";
key "name";
leaf name {
type string;
description
"The name of this rendered function path. This is the same
name as the associated SFP";
}
leaf parent-service-function-path {
type string;
description
"Service Function Path from which this RSP was instantiated";
}
leaf context-metadata {
type sfc-md:context-metadata-ref;
description
"The name of the associated context metadata";
}
leaf variable-metadata {
type sfc-md:variable-metadata-ref;
description
"The name of the associated variable metadata";
}
list rendered-service-path-hop {
key "hop-number";
leaf hop-number {
type uint8;
description
"A Monotonically increasing number";
}
leaf service-function-name {
type string;
description
"Service Function name";
}
leaf service-function-forwarder {
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type string;
description
"Service Function Forwarder name";
}
leaf service-function-forwarder-locator {
type sfc-sff:service-function-forwarder-locator-ref;
description
"The name of the SFF data plane locator";
}
leaf service-index {
type uint8;
description
"Provides location within the service path.
Service index MUST be decremented by service functions
or proxy nodes after performing required services. MAY
be used in conjunction with service path for path
selection. Service Index is also valuable when
troubleshooting/reporting service paths. In addition to
location within a path, SI can be used for loop
detection.";
}
ordered-by user;
description
"A list of service functions that compose the
service path";
}
leaf service-chain-name {
type string;
mandatory true;
description
"The Service Function Chain used as blueprint for this
path";
}
leaf starting-index {
type uint8;
description
"Starting service index";
}
leaf path-id {
type uint32 {
range "0..16777216";
}
description
"Identifies a service path.
Participating nodes MUST use this identifier for path
selection. An administrator can use the service path
value for reporting and troubleshooting packets along
a specific path.";
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}
}
}
rpc delete-rendered-path {
description
"Delete a Rendered Service Path";
input {
leaf name {
type string;
description
"The name of this rendered function path. This is the same
name as the associated SFP";
}
}
output {
leaf result {
type boolean;
}
}
}
rpc create-rendered-path {
description
"Created a Rendered Service Path";
input {
leaf name {
type string;
description
"The name of this rendered function path. This is the same
name as the associated SFP";
}
leaf parent-service-function-path {
type string;
description
"Service Function Path from which this RSP was instantiated";
}
leaf symmetric {
type boolean;
default false;
description
"If the chain is symmetric we will create two service
paths, one ingress and another egress. Packets traverse
the egress service path in the reverse order of the
ingress path";
}
leaf classifier {
type string;
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description "The classifier responsible for directing"
+ "packets to this service path";
}
leaf symmetric-classifier {
type string;
description "The classifier responsible for directing"
+ "packets to this service path";
}
}
output {
leaf result {
type boolean;
}
}
}
container rendered-service-path-first-hop {
description
"Provides all necessary information for a system to construct
a NSH header and associated overlay packet to target the first
service hop of a Rendered Service Path";
leaf starting-index {
type uint8;
description
"Starting service index";
}
leaf symmetric-path-id {
type uint32 {
range "0..16777216";
}
description
"Identifies the associated symmetric path, if any.";
}
leaf path-id {
type uint32 {
range "0..16777216";
}
description
"Identifies a service path.
Participating nodes MUST use this identifier for path
selection. An administrator can use the service path
value for reporting and troubleshooting packets along
a specific path.";
}
leaf transport-type {
type sfc-sl:sl-transport-type-def;
}
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uses sfc-sl:ip-port-locator;
uses sfc-sl:mpls-locator;
}
}
12. Service Function Classifier (SCF)
This module contains a collection of YANG definitions for managing
service classification functions.
12.1. Module Structure
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module: rendered-service-path
+--ro rendered-service-paths
+--ro rendered-service-path* [name]
+--ro name string
+--ro parent-service-function-path? string
+--ro context-metadata? sfc-md:context-metadata-ref
+--ro variable-metadata? sfc-md:variable-metadata-ref
+--ro rendered-service-path-hop* [hop-number]
| +--ro hop-number uint8
| +--ro service-function-name? string
| +--ro service-function-forwarder? string
| +--ro service-index? uint8
+--ro service-chain-name string
+--ro starting-index? uint8
+--ro path-id? uint32
rpcs:
+---x delete-rendered-path
| +--ro input
| | +--ro name? string
| +--ro output
| +--ro result? boolean
+---x create-rendered-path
+--ro input
| +--ro name? string
| +--ro parent-service-function-path? string
| +--ro symmetric? boolean
| +--ro classifier? string
| +--ro symmetric-classifier? string
+--ro output
+--ro result? boolean
12.2. Service Function Classifier Module
file "service-function-classifier@2014-07-01.yang"
module service-function-classifier {
yang-version 1;
namespace "urn:cisco:params:xml:ns:yang:sfc-scf";
prefix sfc-scf;
import ietf-acl {prefix "ietf-acl";}
organization "Cisco Systems, Inc.";
contact "Reinaldo Penno ";
description
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"This module contains a collection of YANG definitions for
managing service classification functions.";
revision 2014-07-01 {
description
"Revised based on Opendaylight Project feedback";
}
grouping attachment-point {
description
"Reusable group of all possible attachment point types";
choice attachment-point-type {
description
"Provides a choice between access list
attachment point types";
case bridge {
leaf bridge {
type string;
description
"OVS bridge as an attachment point";
}
}
case interface {
leaf interface {
type string;
description
"interface name as attachment point";
}
}
}
}
container service-function-classifiers {
description
"Classifier container which represents the ACL being applied,
attachment point and the chain associated with that ACL.";
list service-function-classifier {
description
"A list that holds all service function classifiers";
key "name";
leaf name {
type string;
description
"Classification function name";
}
leaf access-list {
description
"The ACL name associated with this classifier";
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type string;
}
leaf rendered-service-path {
description
"The classifier will direct packets to the SFP
specified here";
type string;
}
list scl-service-function-forwarder {
description
"The classifier will be attached to these SFFs";
key "name";
leaf name {
description
"The classifier will be attached to this SFF";
type string;
}
uses attachment-point {
description "Classifier attachment point";
}
}
}
}
container service-function-classifiers-state {
description
"This container hold operational state for all service
function classifiers";
config false;
list service-function-classifier-state {
description
"This list holds operational data for all service function
classifiers in the domain";
key "name";
leaf name {
type string;
description
"The name of the service function classifier";
}
list scl-rendered-service-path {
key "name";
leaf name {
type string;
description
"The name of the Rendered Service Path";
}
description
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"A list of all rendered service paths that use this classifier";
}
}
}
}
13. Service Function Description Monitor Report (SF-DESC-MON-RPT)
This module for entities implementing the network service functions
for Service Function Chaining
13.1. Module Structure
module: service-function-description-monitor-report
+--rw service-function
+--rw description-info
| +--rw number-of-dataports? uint32
| +--rw capabilities
| +--rw supported-packet-rate? uint32
| +--rw supported-bandwidth? uint32
| +--rw supported-ACL-number? uint32
| +--rw RIB-size? uint32
| +--rw FIB-size? uint32
| +--rw ports-bandwidth
| +--rw port-bandwidth* [port-id]
| +--rw port-id uint32
| +--rw ipaddress? inet:ipv4-address
| +--rw macaddress? yang:mac-address
| +--rw supported-bandwidth? uint32
+--rw monitoring-info
+--rw liveness? boolean
+--rw resource-utilization
+--rw packet-rate-utilization? uint32
+--rw bandwidth-utilization? uint32
+--rw CPU-utilization? uint32
+--rw memory-utilization? uint32
+--rw available-memory? uint32
+--rw RIB-utilization? uint32
+--rw FIB-utilization? uint32
+--rw power-utilization? uint32
+--rw SF-ports-bandwidth-utilization
+--rw port-bandwidth-utilization* [port-id]
+--rw port-id uint32
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+--rw bandwidth-utilization? uint32
rpcs:
+---x get-SF-description
| +--ro output
| +--ro description-info
| +--ro number-of-dataports? uint32
| +--ro capabilities
| +--ro supported-packet-rate? uint32
| +--ro supported-bandwidth? uint32
| +--ro supported-ACL-number? uint32
| +--ro RIB-size? uint32
| +--ro FIB-size? uint32
| +--ro ports-bandwidth
| +--ro port-bandwidth* [port-id]
| +--ro port-id uint32
| +--ro ipaddress? inet:ipv4-address
| +--ro macaddress? yang:mac-address
| +--ro supported-bandwidth? uint32
+---x get-SF-monitoring-info
+--ro output
+--ro monitoring-info
+--ro liveness? boolean
+--ro resource-utilization
+--ro packet-rate-utilization? uint32
+--ro bandwidth-utilization? uint32
+--ro CPU-utilization? uint32
+--ro memory-utilization? uint32
+--ro available-memory? uint32
+--ro RIB-utilization? uint32
+--ro FIB-utilization? uint32
+--ro power-utilization? uint32
+--ro SF-ports-bandwidth-utilization
+--ro port-bandwidth-utilization* [port-id]
+--ro port-id uint32
+--ro bandwidth-utilization? uint32
13.2. Service Function Description Monitor Report Module
file "service-function-description-monitor-report.yang"
module service-function-description-monitor-report {
namespace "urn.intel.params:xml:ns:sf-desc-mon-rpt";
prefix sf-desc-mon-rpt;
import ietf-inet-types { prefix inet;}
import ietf-yang-types { prefix yang;}
organization "Intel Inc.";
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contact "honglix.chen@intel.com";
description
"The module for entities implementing the network service
functions for Service Function Chaining";
revision 2014-11-05 {
description "Initial revision.";
}
grouping SF-description {
leaf number-of-dataports {
type uint32;
description "Number of dataports";
}
container capabilities {
leaf supported-packet-rate {
type uint32;
description "Maximum Mpps supported";
}
leaf supported-bandwidth {
type uint32;
description "Maximum Mbps supported ";
}
leaf supported-ACL-number {
type uint32;
description "ACL number of the service function";
}
leaf RIB-size {
type uint32;
description "Number of Routing Information Table's entries.";
}
leaf FIB-size {
type uint32;
description "Number of Forwarding Information Table's entries.";
}
container ports-bandwidth {
list port-bandwidth {
key port-id;
leaf port-id {
type uint32;
description "The id of the port ";
}
leaf ipaddress {
type inet:ipv4-address;
description "IP address of the port";
}
leaf macaddress {
type yang:mac-address;
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description "MAC address of the the port";
}
leaf supported-bandwidth {
type uint32;
description "Maximum Mbps supported by the port";
}
}
}
}
}
grouping SF-monitoring-info {
leaf liveness {
type boolean;
description "Liveness flag of the service function";
}
container resource-utilization {
leaf packet-rate-utilization {
type uint32;
description "Percentage of current package rate utilization.";
}
leaf bandwidth-utilization {
type uint32;
description "Percentage of bandwidth utilization.";
}
leaf CPU-utilization {
type uint32;
description "Percentage of CPU utilization.";
}
leaf memory-utilization {
type uint32;
description "Percentage of memory utilization.";
}
leaf available-memory {
type uint32;
description "Available memory size of the service function in MB.";
}
leaf RIB-utilization {
type uint32;
description "Percentage of Routing Information Table utilization.";
}
leaf FIB-utilization {
type uint32;
description "Percentage of Forwarding Information Table utilization.";
}
leaf power-utilization {
type uint32;
description "power utilization in W.";
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}
container SF-ports-bandwidth-utilization {
list port-bandwidth-utilization {
key port-id;
leaf port-id {
type uint32;
description "The id of the port ";
}
leaf bandwidth-utilization {
type uint32;
description "Percentage of the port's supported bandwidth utilization.";
}
}
}
}
}
container service-function {
container description-info {
uses SF-description;
}
container monitoring-info {
uses SF-monitoring-info;
}
}
rpc get-SF-description {
description
"Get service function description information.";
output {
container description-info {
uses SF-description;
}
}
}
rpc get-SF-monitoring-info {
description
"Get current service function monitoring information.";
output {
container monitoring-info {
uses SF-monitoring-info;
}
}
}
}
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14. Service Function Description Monitor (SF-DESC-MON)
This module is used to create description and monitoring information
of Service Function extensions to service-function model
14.1. Module Structure
module service-function-description-monitor {
namespace "urn.intel.params:xml:ns:sf-desc-mon";
prefix sf-desc-mon;
import service-function { prefix sfc-sf;}
import service-function-description-monitor-report { prefix sf-desc-mon-rpt;}
organization "Intel Inc.";
contact "honglix.chen@intel.com";
description
"Create description and monitoring information of Service
Function extensions to service-function model";
revision 2014-12-01 {
description "Initial revision.";
}
augment "/sfc-sf:service-functions-state/sfc-sf:service-function-state" {
description "Service function description and monitoring information";
container sfc-sf-desc-mon {
container description-info {
uses sf-desc-mon-rpt:SF-description;
}
container monitoring-info {
uses sf-desc-mon-rpt:SF-monitoring-info;
}
}
}
}
14.2. Service Function Description Monitor Report Module
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file "service-function-description-monitor.yang"
module service-function-description-monitor {
namespace "urn.intel.params:xml:ns:sf-desc-mon";
prefix sf-desc-mon;
import service-function { prefix sfc-sf;}
import service-function-description-monitor-report { prefix sf-desc-mon-rpt;}
organization "Intel Inc.";
contact "honglix.chen@intel.com";
description
"Create description and monitoring information of Service
Function extensions to service-function model";
revision 2014-12-01 {
description "Initial revision.";
}
augment "/sfc-sf:service-functions-state/sfc-sf:service-function-state" {
description "Service function description and monitoring information";
container sfc-sf-desc-mon {
container description-info {
uses sf-desc-mon-rpt:SF-description;
}
container monitoring-info {
uses sf-desc-mon-rpt:SF-monitoring-info;
}
}
}
}
15. IANA Considerations
TBD
16. Security Considerations
17. Acknowledgements
Thanks to Jan Medved, Ron Parker, Jan Lindblad, David Goldberg, Vina
Ermagan, Sam Hague and Vinayak Joshi and for reviews and suggestions.
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18. Changes
-11
o Added new co-authors
o changed RSP and SFP models to allow multiple encap paths.
o Added the "need reclassififcation" leaf to allow a Service
Function to tell a SFF that packet reclassification is needed
o Added RSP first hop container to allow SFC applications to request
the ingress hop to a RSP. These applciations (such as dynamic
classifier) treat RSP as a black box and only need ingress
locator.
-10
This new revision comes after considerable control and dataplane
interop testing. The new changes reflect what we found necessary for
building a well-rounded solution.
o Added Rendered Service Path Model
o Added Service Function Description Monitor and Report Models
o Updated Service Function Path (It allow users to control certain
aspects of RSPs, new symmetric and metadata leaves)
o Updated Service Function Forwarder model
o Updated Service Function Model
o Updated Service Function Type Model (HTTP Header Enrichment
service)
o Update Service Locator Model (MPLS encap)
o Removed Service Node
o Others
-09
o Modifed Service Function Forwarder OVS model based on OVS/
Openstack deployment experience
-08
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o Removed VXLAN-GPE model
o Added Service Function Forwarder OVS model
o Added metadata reference to Service Function Path
-07
o All models that need data plane locators reference service locator
model
o Service Locator module has locators for IP:port, VLAN:MAC, LISP
o A SF can have multiple data place locators
o SF and SFF are decoupled and have their own views of the network
o Service Function Chains and derived path can be symmtric (bi-dir)
or not
o Service Function Types separated into a model
o Service Function Path is a collection of service hops. This
allows hops such as SFF + classifier.
-06
o Introduced operational tree in some models based on testing and
user feedback.
o Introduced RPCs in some models
o Service Function Path needs SFC from which it will be instantiated
o Updated all module structures
o Introduced Service Locator module
-05
Changes based on Opendaylight Implementation Testing and Sfc-dev
mailing list feedback
o Service Node becomes a container for Service Functions. Moved
data plane items to SFF.
o Fixed Service Function Forwarders into a list so we cna have
multiple in a system
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o Fixed Service Function Chain so it becomes a list of lists.
o Created RPCs for Service Functions and Service Chain
-04
o Fixed list inside Service Function Chain to read service-function-
type
o Small comment fixes
-03
o Revision dates consistent
o Service function chain to container + list in order to allow
multiple
o Service Function Path to cotainer + list
o VXLAN-gpe vni to multiple 8-bit fields
o Consistent typeref use
o Other consistency fixes
-02
o After Opendaylight Testing converted multiple leafs to lists
throughout all models
o Removed transport dependency. Transport could be layer-2, layer-
3, etc
o Used pathrefs similar to ietf-interfaces to reference
configuration names
o Other consistency fixes
19. References
19.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
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[RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext
Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.
19.2. Informative References
[I-D.ietf-sfc-architecture]
Halpern, J. and C. Pignataro, "Service Function Chaining
(SFC) Architecture", draft-ietf-sfc-architecture-05 (work
in progress), February 2015.
[I-D.ietf-sfc-problem-statement]
Quinn, P. and T. Nadeau, "Service Function Chaining
Problem Statement", draft-ietf-sfc-problem-statement-13
(work in progress), February 2015.
[I-D.quinn-sfc-nsh]
Quinn, P., Guichard, J., Surendra, S., Smith, M.,
Henderickx, W., Nadeau, T., Agarwal, P., Manur, R.,
Chauhan, A., Halpern, J., Majee, S., Elzur, U., Melman,
D., Garg, P., McConnell, B., Wright, C., and K. Kevin,
"Network Service Header", draft-quinn-sfc-nsh-07 (work in
progress), February 2015.
[I-D.quinn-vxlan-gpe]
Quinn, P., Manur, R., Kreeger, L., Lewis, D., Maino, F.,
Smith, M., Agarwal, P., Yong, L., Xu, X., Elzur, U., Garg,
P., and D. Melman, "Generic Protocol Extension for VXLAN",
draft-quinn-vxlan-gpe-04 (work in progress), February
2015.
Authors' Addresses
Reinaldo Penno
Cisco Systems
170 West Tasman Dr
San Jose CA
USA
Email: repenno@cisco.com
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Paul Quinn
Cisco Systems
170 West Tasman Dr
San Jose CA
USA
Email: paulq@cisco.com
Danny Zhou
Intel Corporation
2200 Mission College Blvd.
Santa Clara CA
USA
Email: danny.zhou@intel.com
Johnson Li
Intel Corporation
2200 Mission College Blvd.
Santa Clara CA
USA
Email: johnson.li@intel.com
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