YANG Data Model for ARP
draft-ding-rtgwg-arp-yang-model-01
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| Document | Type |
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|---|---|---|---|
| Authors | ding xiaojian, Feng Zheng , Robert Wilton | ||
| Last updated | 2018-02-28 | ||
| Replaces | draft-ding-netmod-arp-yang-model | ||
| Replaced by | draft-ietf-rtgwg-arp-yang-model, draft-ietf-rtgwg-arp-yang-model | ||
| RFC stream | (None) | ||
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draft-ding-rtgwg-arp-yang-model-01
RTGWG X. Ding
Internet-Draft F. Zheng
Intended status: Standards Track Huawei
Expires: August 31, 2018 R. Wilton
Cisco Systems
February 27, 2018
YANG Data Model for ARP
draft-ding-rtgwg-arp-yang-model-01
Abstract
This document defines a specification of one YANG module and one
submodule. Together they form the Address Resolution Protocol (ARP)
data model that performs as a guideline for configuring ARP
capabilities on a system. It is intended these modules be used by
service providers who manipulate devices from different vendors in a
standard way.
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 https://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 August 31, 2018.
Copyright Notice
Copyright (c) 2018 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
(https://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
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include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3
1.2. Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . 3
2. Problem Statement . . . . . . . . . . . . . . . . . . . . . . 3
3. Design of the Data Model . . . . . . . . . . . . . . . . . . 4
3.1. ietf-arp Module . . . . . . . . . . . . . . . . . . . . . 4
3.2. ietf-arp-dynamic-learning Submodule . . . . . . . . . . . 5
4. ARP YANG Module . . . . . . . . . . . . . . . . . . . . . . . 6
4.1. ARP Dynamic Learning Submodule . . . . . . . . . . . . . 9
5. Data Model Examples . . . . . . . . . . . . . . . . . . . . . 14
5.1. Static ARP Entries . . . . . . . . . . . . . . . . . . . 14
5.2. ARP Dynamic Learning . . . . . . . . . . . . . . . . . . 14
6. Security Considerations . . . . . . . . . . . . . . . . . . . 15
7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 16
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
8.1. Normative References . . . . . . . . . . . . . . . . . . 16
8.2. Informative References . . . . . . . . . . . . . . . . . 16
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17
1. Introduction
This document defines a YANG [RFC6020] data model for Address
Resolution Protocol [RFC826] implementation and identification of
some common properties within a device containing a Network
Configuration Protocol (NETCONF) server. Devices that are managed by
NETCONF and perhaps other mechanisms have common properties that need
to be configured and monitored in a standard way.
This document contains a specification of the following YANG modules:
o The "ietf-arp" module provides generic abilities of a ARP data
model. This module is used for global ARP configurations.
o The submodule "ietf-arp-dynamic-learning" augments the "ietf-
interfaces" [I-D.ietf-netmod-rfc7223bis] and "ietf-ip" [I-D.ietf-
netmod-rfc7277bis] modules with additional data specification to
ARP confifuration on interfaces.
These YANG modules cover configuration of system parameters of ARP,
such as static ARP entries, timeout for dynamic ARP entries,
interface ARP, proxy ARP, and so on. They also provide information
about running state of ARP implementations.
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1.1. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14, [RFC2119].
The following terms are defined in [RFC6241] and are not redefined
here:
o client
o configuration data
o server
o state data
1.2. Tree Diagrams
A simplified graphical representation of the data model is presented
in Section 3.
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, "!"
means a presence container, 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. Problem Statement
This document defines a YANG [RFC7950] configuration data model that
may be used to configure the ARP feature running on a system. YANG
model can be used with network management protocols such as NETCONF
[RFC6241] to install, manipulate, and delete the configuration of
network devices.
The data model makes use of the YANG "feature" construct which allows
implementations to support only those ARP features that lie within
their capabilities. It is intended this model be used by service
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providers who manipulate devices from different vendors in a standard
way.
This model can be used to configure the ARP applications for
discovering the link layer address associated with a given Internet
layer address.
3. Design of the Data Model
This data model intends to describe the processing that a protocol
finds the hardware address, also known as Media Access Control (MAC)
address, of a host from its known IP address. These tasks include,
but are not limited to, adding a static entry in the ARP cache,
configuring ARP cache entry timeout, and clearing dynamic entries
from the ARP cache.
The ARP data model consists of one YANG module and one submodule.
The first module, "ietf-arp", defines the generic abilities of ARP
configurations. Its submodule, "ietf-arp-dynamic-learning", augments
the "ietf-interfaces" [I-D.ietf-netmod-rfc7223bis] and "ietf-ip" [I-
D.ietf-netmod-rfc7277bis] modules with additional data specification
to ARP confifuration on interfaces.
3.1. ietf-arp Module
This module has one top level container, ARP, which consists of two
second level containers. Each of these second level containers
describes a particular category of ARP handling, such as defining
static mapping between an IP address (32-bit address) and a Media
Access Control (MAC) address (48-bit address).
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module: ietf-arp
+--rw arp
+--rw global-static-table {global-static-table}?
| +--rw static-entry* [ip-address]
| +--rw ip-address inet:ipv4-address-no-zone
| +--rw mac-address yang:mac-address
+--ro statistics
+--ro in-requests-pkts? uint64
+--ro in-replies-pkts? uint64
+--ro in-gratuitous-pkts? uint64
+--ro out-requests-pkts? uint64
+--ro out-replies-pkts? uint64
+--ro out-gratuitous-pkts? uint64
+--ro in-drops? uint64
+--ro in-total? uint64
+--ro out-total? uint64
+--ro all-dynamic-pkts? uint64
+--ro all-static-pkts? uint64
3.2. ietf-arp-dynamic-learning Submodule
submodule: ietf-arp-dynamic-learning (belongs-to ietf-arp)
augment /if:interfaces/if:interface:
+--rw arp-dynamic-learning
+--rw expire-time? uint32
+--rw learn-disable? boolean
+--rw proxy-enable? boolean
+--rw if-limit* [vlan-id]
| +--rw vlan-id uint16
| +--rw limit-number uint32
| +--rw threshold-value? uint32
+--rw probe
| +--rw interval? uint8
| +--rw times? uint8
| +--rw unicast? boolean
+--rw gratuitous
| +--rw gratuitous-enable? boolean
| +--rw interval? uint32
| +--rw drop? boolean
+--ro statistics
+--ro in-requests-pkts? uint64
+--ro in-replies-pkts? uint64
+--ro in-gratuitous-pkts? uint64
+--ro out-requests-pkts? uint64
+--ro out-replies-pkts? uint64
+--ro out-gratuitous-pkts? uint64
augment /if:interfaces/if:interface/ip:ipv4/ip:neighbor:
+--ro remaining-expire-time? uint32
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4. ARP YANG Module
This section presents the ARP YANG module defined in this document.
This YANG module imports typedefs from [RFC6991].
<CODE BEGINS> file "ietf-arp@2018-01-27.yang"
module ietf-arp {
namespace "urn:ietf:params:xml:ns:yang:ietf-arp";
prefix arp;
import ietf-inet-types {
prefix inet;
}
import ietf-yang-types {
prefix yang;
}
organization
"IETF Routing Area Working Group (rtgwg)";
contact
"WG Web: <http://tools.ietf.org/wg/rtgwg/>
WG List: <mailto: rtgwg@ietf.org>
Editor: Xiaojian Ding
dingxiaojian1@huawei.com
Editor: Feng Zheng
habby.zheng@huawei.com
Editor: Robert Wilton
rwilton@cisco.com";
description
"Address Resolution Protocol (ARP) management, which includes
static ARP configuration, dynamic ARP learning, ARP entry query,
and packet statistics collection.";
revision 2017-10-18 {
description
"Init revision";
reference "RFC XXX: ARP (Address Resolution Protocol) YANG data model.";
}
feature global-static-table {
description
"This feature indicates that the device allows static entries
to be configured globally.";
}
container arp {
description
"Address Resolution Protocol (ARP) management, which includes
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static ARP configuration, dynamic ARP learning, ARP entry
query, and packet statistics collection.";
container global-static-table {
if-feature "global-static-table";
description
"Set a global static ARP entry, which is independent of the interface.";
list static-entry {
key "ip-address";
description
"List of ARP static entries that can be configured globally.";
leaf ip-address {
type inet:ipv4-address-no-zone;
description
"IP address, in dotted decimal notation.";
}
leaf mac-address {
type yang:mac-address;
mandatory true;
description
"MAC address in the format of H-H-H, in which H is
a hexadecimal number of 1 to 4 bits.";
}
}
}
container statistics {
config false;
description
"List of ARP packet statistics.";
leaf in-requests-pkts {
type uint64;
description
"Total ARP requests received";
}
leaf in-replies-pkts {
type uint64;
description
"Total ARP replies received";
}
leaf in-gratuitous-pkts {
type uint64;
description
"Total gratuitous ARP received";
}
leaf out-requests-pkts {
type uint64;
description
"Total ARP requests sent";
}
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leaf out-replies-pkts {
type uint64;
description
"Total ARP replies sent";
}
leaf out-gratuitous-pkts {
type uint64;
description
"Total gratuitous ARP sent";
}
leaf in-drops {
type uint64 {
range "0..4294967294";
}
description
"Number of ARP packets discarded.";
}
leaf in-total {
type uint64 {
range "0..4294967294";
}
description
"Total number of ARP received packets.";
}
leaf out-total {
type uint64 {
range "0..4294967294";
}
description
"Total number of ARP sent packets.";
}
leaf all-dynamic-pkts {
type uint64 {
range "0..4294967294";
}
description
"Number of dynamic ARP packets count.";
}
leaf all-static-pkts {
type uint64 {
range "0..4294967294";
}
description
"Number of static ARP packets count.";
}
}
}
}
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<CODE ENDS>
4.1. ARP Dynamic Learning Submodule
<CODE BEGINS> file "ietf-arp-dynaminc-learning@2018-01-27.yang"
submodule ietf-arp-dynamic-learning {
yang-version 1.1;
belongs-to ietf-arp {
prefix arp;
}
import ietf-interfaces {
prefix if;
description
"A Network Management Datastore Architecture (NMDA)
compatible version of the ietf-interfaces module
is required.";
}
import ietf-ip {
prefix ip;
description
"A Network Management Datastore Architecture (NMDA)
compatible version of the ietf-ip module is
required.";
}
organization
"IETF Routing Area Working Group (rtgwg)";
contact
"WG Web: <http://tools.ietf.org/wg/rtgwg/>
WG List: <mailto: rtgwg@ietf.org>
Editor: Xiaojian Ding
dingxiaojian1@huawei.com
Editor: Feng Zheng
habby.zheng@huawei.com
Editor: Robert Wilton
rwilton@cisco.com";
description
"This YANG module augments 'ietf-if' and 'ietf-ip'
modules with parameters for ARP configuration on interfaces.
The model fully conforms to the Network Management
Datastore Architecture (NMDA).
Copyright (c) 2017 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
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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.";
revision 2018-01-27 {
description
"Initial revision.";
reference "RFC XXX: ARP (Address Resolution Protocol) YANG data model";
}
augment "/if:interfaces/if:interface" {
description
"Augment interface configuration with parameters of ARP.";
container arp-dynamic-learning {
description
"Support for ARP configuration on interfaces.";
leaf expire-time {
type uint32 {
range "60..86400";
}
units "second";
description
"Aging time of a dynamic ARP entry.";
}
leaf learn-disable {
type boolean;
default "false";
description
"Whether dynamic ARP learning is disabled. If the value
is True, dynamic ARP learning is disabled. If the value
is False, dynamic ARP learning is enabled.";
}
leaf proxy-enable {
type boolean;
default "false";
description
"Enable proxy ARP.";
}
list if-limit {
key "vlan-id";
description
"Maximum number of dynamic ARP entries that an
interface can learn. If the number of ARP entries that
an interface can learn changes and the number of the
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learned ARP entries exceeds the changed value, the
interface cannot learn additional ARP entries. The
system prompts you to delete the excess ARP entries.";
leaf vlan-id {
type uint16 {
range "0..4094";
}
description
"ID of the VLAN where ARP learning is restricted.
This parameter can be set only on Layer 2 interfaces
and sub-interfaces. Ethernet, GE, VE, and Eth-Trunk
interfaces can be both Layer 3 and Layer 2
interfaces. When they work in Layer 3 mode, they
cannot have VLANs configured. When they work in Layer
2 mode, they must have VLANs configured. Ethernet,
GE, and Eth-Trunk sub-interfaces can be both common
and QinQ sub-interfaces. ";
}
leaf limit-number {
type uint32 {
range "1..65536";
}
mandatory true;
description
"Maximum number of dynamic ARP entries that an
interface can learn.";
}
leaf threshold-value {
type uint32 {
range "60..100";
}
must "not(not(../limit-number))" {
description
"Upper boundary must be higher than lower boundary.";
}
description
"Alarm-Threshold for Maximum number of ARP entries
that an interface can learn.";
}
}
container probe {
description
"Common configuration parameters for all ARP probe.";
leaf interval {
type uint8 {
range "1..5";
}
units "second";
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description
"Interval for detecting dynamic ARP entries.";
}
leaf times {
type uint8 {
range "0..10";
}
description
"Number of aging probe attempts for a dynamic ARP entry.
If a device does not receive an ARP reply message after
the number of aging probe attempts reaches a specified
number,thedynamic ARP entry is deleted.";
}
leaf unicast {
type boolean;
default "false";
description
"Send unicast ARP aging probe messages for a dynamic ARP
entry.";
}
}
container gratuitous {
description
"Configure gratuitous ARP.";
leaf gratuitous-enable {
type boolean;
default "false";
description
"Enable or disable sending gratuitous-arp packet on
interface.";
}
leaf interval {
type uint32 {
range "1..86400";
}
units "second";
description
"The interval of sending gratuitous-arp packet on the
interface.";
}
leaf drop {
type boolean;
default "false";
description
"Drop the receipt of gratuitous ARP packets on the interface.";
}
}
container statistics {
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config false;
description
"IP ARP Statistics information on interfaces";
leaf in-requests-pkts {
type uint64;
description
"Total ARP requests received";
}
leaf in-replies-pkts {
type uint64;
description
"Total ARP replies received";
}
leaf in-gratuitous-pkts {
type uint64;
description
"Total gratuitous ARP received";
}
leaf out-requests-pkts {
type uint64;
description
"Total ARP requests sent";
}
leaf out-replies-pkts {
type uint64;
description
"Total ARP replies sent";
}
leaf out-gratuitous-pkts {
type uint64;
description
"Total gratuitous ARP sent";
}
}
}
}
augment "/if:interfaces/if:interface/ip:ipv4/ip:neighbor" {
description
"Augment neighbor list with parameters of ARP,
eg., support for remaining expire time query on interfaces.";
leaf remaining-expire-time {
type uint32;
config false;
description
"Remaining expire time of a dynamic ARP entry. ";
}
}
}
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<CODE ENDS>
5. Data Model Examples
This section presents a simple but complete example of configuring
static ARP entries and dynamic learning, based on the YANG modules
specified in Section 4.
5.1. Static ARP Entries
Requirement:
Enable static ARP entry global configuration (not rely on interface).
<config xmlns:xc="urn:ietf:params:xml:ns:netconf:base:1.0">
<arp xmlns="urn:ietf:params:xml:ns:yang:ietf-arp">
<static-tables>
<ip-address> 10.2.2.3 </ip-address>
<mac-address> 00e0-fc01-0000 </mac-address>
</static-tables>
</arp>
Requirement:
Enable static ARP entry configuration on interface (defined in
draft [I-D.ietf-netmod-rfc7277bis]).
<config xmlns:xc="urn:ietf:params:xml:ns:netconf:base:1.0">
<ipv4 xmlns="urn:ietf:params:xml:ns:yang:ietf-ip">
<neighbor>
<vrf-name> __public__ </vrf-name>
<ip-address> 10.2.2.3 </ip-address>
<mac-address> 00e0-fc01-0000 </mac-address>
<if-name> GE1/0/1 </if-name>
</neighbor>
</ipv4>
5.2. ARP Dynamic Learning
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Requirement:
Enable ARP dynamic learning configuration.
<config xmlns:xc="urn:ietf:params:xml:ns:netconf:base:1.0">
<arp-dynamic-learning xmlns="urn:ietf:params:xml:ns:yang:ietf-arp-dynamic-learning">
<if-name> GE1/0/1 </if-name>
<expire-time>1200</expire-time>
<learn-disable>false</learn-disable>
<proxy-enable>false</proxy-enable>
<arp-if-limits>
<vlan-id>3</vlan-id>
<limit-number>65535</limit-number>
<threshold-value>80</threshold-value>
</arp-if-limits>
<probe>
<interval>5</interval>
<times>3</times>
<unicast>false</unicast>
</probe>
<gratuitous>
<gratuitous-enable>false<gratuitous-enable>
<interval>60</interval>
<drop>false</drop>
<gratuitous>
</arp-dynamic-learning>
6. Security Considerations
The YANG module defined in this document is designed to be accessed
via YANG based management protocols, such as NETCONF [RFC6241] and
RESTCONF [RFC8040]. Both of these protocols have mandatory-to-
implement secure transport layers (e.g., SSH, TLS) with mutual
authentication.
The NETCONF access control model (NACM) [RFC6536] provides the means
to restrict access for particular users to a pre-configured subset of
all available protocol operations and content.
These are the subtrees and data nodes and their sensitivity/
vulnerability:
There are a number of data nodes defined in this YANG module that are
writable/creatable/deletable (i.e., config true, which is the
default). These data nodes may be considered sensitive or vulnerable
in some network environments. Write operations (e.g., edit-config)
to these data nodes without proper protection can have a negative
effect on network operations.
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7. Acknowledgments
The authors wish to thank Alex Campbell and Reshad Rahman, Qin Wu,
many others for their helpful comments.
8. References
8.1. Normative References
[I-D.ietf-netmod-rfc7223bis]
Bjorklund, M., "A YANG Data Model for Interface
Management", draft-ietf-netmod-rfc7223bis-03 (work in
progress), January 2018.
[I-D.ietf-netmod-rfc7277bis]
Bjorklund, M., "A YANG Data Model for IP Management",
draft-ietf-netmod-rfc7277bis-03 (work in progress),
January 2018.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://www.rfc-editor.org/info/rfc2119>.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<https://www.rfc-editor.org/info/rfc6020>.
[RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types",
RFC 6991, DOI 10.17487/RFC6991, July 2013,
<https://www.rfc-editor.org/info/rfc6991>.
[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016,
<https://www.rfc-editor.org/info/rfc7950>.
8.2. Informative References
[RFC0826] Plummer, D., "Ethernet Address Resolution Protocol: Or
Converting Network Protocol Addresses to 48.bit Ethernet
Address for Transmission on Ethernet Hardware", STD 37,
RFC 826, DOI 10.17487/RFC0826, November 1982,
<https://www.rfc-editor.org/info/rfc826>.
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[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<https://www.rfc-editor.org/info/rfc6241>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/info/rfc8040>.
Authors' Addresses
Xiaojian Ding
Huawei
101 Software Avenue, Yuhua District
Nanjing, Jiangsu 210012
China
Email: dingxiaojian1@huawei.com
Feng Zheng
Huawei
101 Software Avenue, Yuhua District
Nanjing, Jiangsu 210012
China
Email: habby.zheng@huawei.com
Robert Wilton
Cisco Systems
Email: rwilton@cisco.com
Ding, et al. Expires August 31, 2018 [Page 17]