<?xml version='1.0'encoding='utf-8'?>encoding='UTF-8'?> <!DOCTYPE rfc [ <!ENTITY nbsp " "> <!ENTITY zwsp "​"> <!ENTITY nbhy "‑"> <!ENTITY wj "⁠"> ]><?rfc toc="yes"?> <?rfc symrefs="yes"?> <?rfc sortrefs="yes" ?> <?rfc compact="yes"?> <?rfc subcompact="no"?> <?rfc linkmailto="no" ?> <?rfc editing="no" ?> <?rfc comments="yes" ?> <?rfc inline="yes"?> <?rfc rfcedstyle="yes"?> <?rfc-ext allow-markup-in-artwork="yes" ?> <?rfc-ext include-index="no" ?> <!--<?rfc strict="no"?> --><rfc xmlns:xi="http://www.w3.org/2001/XInclude" category="std" consensus="true" submissionType="IETF" docName="draft-ietf-netconf-tcp-client-server-26" number="9643" updates="" obsoletes="" ipr="trust200902" tocInclude="true" symRefs="true" sortRefs="true"version="3"> <!-- xml2rfc v2v3 conversion 3.17.4 -->version="3" xml:lang="en"> <front> <title abbrev="Groupings for TCP Clients and Servers">YANG Groupings for TCP Clients and TCP Servers</title> <seriesInfoname="Internet-Draft" value="draft-ietf-netconf-tcp-client-server-26"/>name="RFC" value="9643"/> <author fullname="Kent Watsen" initials="K." surname="Watsen"> <organization>Watsen Networks</organization> <address> <email>kent+ietf@watsen.net</email> </address> </author> <author fullname="Michael Scharf" initials="M." surname="Scharf"> <organization abbrev="Hochschule Esslingen"> Hochschule Esslingen - University of Applied Sciences </organization> <address> <email>michael.scharf@hs-esslingen.de</email> </address> </author><date/> <area>Operations</area> <workgroup>NETCONF Working Group</workgroup><date month="August" year="2024"/> <area>OPS</area> <workgroup>netconf</workgroup> <!-- [rfced] Please insert any keywords (beyond those that appear in the title) for use on https://www.rfc-editor.org/search. --> <keyword>example</keyword> <abstract> <!-- [rfced] We are having trouble parsing this sentence. Does it mean the modules can be configurd to work in conjuntion with other stack layers? Note: Similar text in the Introduction would also be updated. Original: The modules can be used either standalone or in conjunction with configuration of other stack protocol layers. --> <t>This document presents three YANG 1.1 modules to support the configuration of TCP clients and TCP servers. The modules include basic parameters of a TCP connection relevant for client or server applications, as well as client configuration required for traversing proxies. The modules can be used either standalone or in conjunction with configuration of other stack protocol layers.</t> </abstract><note> <name>Editorial Note (To be removed by RFC Editor)</name> <t>This draft contains placeholder values that need to be replaced with finalized values at the time of publication. This note summarizes all of the substitutions that are needed. No other RFC Editor instructions are specified elsewhere in this document.</t> <t>Artwork in this document contains shorthand references to drafts in progress. Please apply the following replacements: </t> <ul spacing="normal"> <li> <tt>AAAA</tt> --> the assigned RFC value for draft-ietf-netconf-crypto-types</li> <li> <tt>DDDD</tt> --> the assigned RFC value for this draft</li> </ul> <t>Artwork in this document contains placeholder values for the date of publication of this draft. Please apply the following replacement: </t> <ul spacing="normal"> <li> <tt>2024-04-04</tt> --> the publication date of this draft</li> </ul> <t>The "Relation to other RFCs" section <xref target="collective-effort"/> contains the text "one or more YANG modules" and, later, "modules". This text is sourced from a file in a context where it is unknown how many modules a draft defines. The text is not wrong as is, but it may be improved by stating more directly how many modules are defined.</t> <t>The "Relation to other RFCs" section <xref target="collective-effort"/> contains a self-reference to this draft, along with a corresponding reference in the Appendix. Please replace the self-reference in this section with "This RFC" (or similar) and remove the self-reference in the "Normative/Informative References" section, whichever it is in.</t> <t>Tree-diagrams in this draft may use the '\' line-folding mode defined in RFC 8792. However, nicer-to-the-eye is when the '\\' line-folding mode is used. The AD suggested suggested putting a request here for the RFC Editor to help convert "ugly" '\' folded examples to use the '\\' folding mode. "Help convert" may be interpreted as, identify what looks ugly and ask the authors to make the adjustment.</t> <t>The following Appendix section is to be removed prior to publication: </t> <ul spacing="normal"> <li> <xref target="change-log"/>. Change Log</li> </ul> </note></front> <middle> <section> <name>Introduction</name> <t>This document defines three YANG 1.1 <xref target="RFC7950"/> modules to support the configuration of TCP clients and TCP servers (TCP is defined in <xref target="RFC9293"/>), either as standalone or in conjunction with configuration of other stack protocol layers.</t> <t>The modules focus on three different types of base TCP parameters that matter for TCP-based applications: First, the modules cover fundamental configuration of a TCP client or TCP server application, such as addresses and port numbers. Second, a reusable grouping enables modification of application-specific parameters foraTCP connections, such as use of TCP keep-alives. And third, client configuration for traversing proxies is included as well. In each case, the modules have a very narrow scope and focus on a minimum set of required parameters.</t> <t>Please be advised that while this document presents support for some TCP proxy techniques, there are other TCP proxy techniques that are not part of thisdocument,document but could be added by augmenting the YANG module.</t> <section anchor="collective-effort"> <name>Relation tootherOther RFCs</name> <t>This document presentsone or morethree YANG modules <xref target="RFC7950"/> that are part of a collection of RFCs that work togetherto, ultimately,to ultimately support the configuration of both the clients and servers of both theNETCONFNetwork Configuration Protocol (NETCONF) <xref target="RFC6241"/> and RESTCONF <xreftarget="RFC8040"/> protocols.</t>target="RFC8040"/>.</t> <t> The dependency relationship between the primary YANG groupings defined in the various RFCs is presented in the below diagram. In some cases, adraftdocument may define secondary groupings that introduce dependencies not illustrated in the diagram. The labels in the diagram areashorthandnamenames for the definingRFC.RFCs. The citationreferencereferences for shorthandname isnames are provided below the diagram.</t> <t>Please note that the arrows in the diagram point from referencer to referenced. For example, the "crypto-types" RFC does not have any dependencies, whilst the "keystore" RFC depends on the "crypto-types" RFC.</t> <artwork><![CDATA[ crypto-types ^ ^ / \ / \ truststore keystore ^ ^ ^ ^ | +---------+ | | | | | | | +------------+ | tcp-client-server | / | | ^ ^ ssh-client-server | | | | ^ tls-client-server | | | ^ ^ http-client-server | | | | | ^ | | | +-----+ +---------+ | | | | | | | | +-----------|--------|--------------+ | | | | | | | | +-----------+ | | | | | | | | | | | | | | | | | netconf-client-server restconf-client-server ]]></artwork><!-- RFC Editor: is there anyway to flush-left the table in PDF/HTML views? --> <table><table align="left"> <name>Label in Diagram to RFC Mapping</name> <tbody> <tr> <th>Label in Diagram</th><th>Originating RFC</th><th>Reference</th> </tr> <tr> <td>crypto-types</td> <td> <xreftarget="I-D.ietf-netconf-crypto-types"/></td>target="RFC9640"/></td> </tr> <tr> <td>truststore</td> <td> <xreftarget="I-D.ietf-netconf-trust-anchors"/></td>target="RFC9641"/></td> </tr> <tr> <td>keystore</td> <td> <xreftarget="I-D.ietf-netconf-keystore"/></td>target="RFC9642"/></td> </tr> <tr> <td>tcp-client-server</td> <td><xref target="I-D.ietf-netconf-tcp-client-server"/></td>RFC 9643</td> </tr> <tr> <td>ssh-client-server</td> <td> <xreftarget="I-D.ietf-netconf-ssh-client-server"/></td>target="RFC9644"/></td> </tr> <tr> <td>tls-client-server</td> <td> <xreftarget="I-D.ietf-netconf-tls-client-server"/></td>target="RFC9645"/></td> </tr> <tr> <td>http-client-server</td> <td> <xref target="I-D.ietf-netconf-http-client-server"/></td> </tr> <tr> <td>netconf-client-server</td> <td> <xref target="I-D.ietf-netconf-netconf-client-server"/></td> </tr> <tr> <td>restconf-client-server</td> <td> <xref target="I-D.ietf-netconf-restconf-client-server"/></td> </tr> </tbody> </table> </section> <section> <name>Specification Language</name><t>The<t> The key words"MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY","<bcp14>MUST</bcp14>", "<bcp14>MUST NOT</bcp14>", "<bcp14>REQUIRED</bcp14>", "<bcp14>SHALL</bcp14>", "<bcp14>SHALL NOT</bcp14>", "<bcp14>SHOULD</bcp14>", "<bcp14>SHOULD NOT</bcp14>", "<bcp14>RECOMMENDED</bcp14>", "<bcp14>NOT RECOMMENDED</bcp14>", "<bcp14>MAY</bcp14>", and"OPTIONAL""<bcp14>OPTIONAL</bcp14>" in this document are to be interpreted as described inBCP 14BCP 14 <xref target="RFC2119"/> <xref target="RFC8174"/> when, and only when, they appear in all capitals, as shownhere.</t>here. </t> </section> <section> <name>Adherence to the NMDA</name> <t>This document is compliant with the Network Management Datastore Architecture (NMDA) <xref target="RFC8342"/>. It does not define any protocol accessible nodes that are "config false".</t> </section> </section> <section anchor="tcp-common-model"> <name>The "ietf-tcp-common" Module</name> <t>This section defines a YANG 1.1 module called "ietf-tcp-common". A high-level overview of the module is provided in <xref target="common-overview"/>. Examples illustrating the module's use are provided in <xreftarget="common-examples">Examples</xref>.target="common-examples"/> ("Example Usage"). The YANG module itself is defined in <xref target="common-yang-module"/>.</t> <section anchor="common-overview"> <name>Data Model Overview</name> <t>This section provides an overview of the "ietf-tcp-common" module in terms of its features and groupings.</t> <section toc="exclude"> <name>Model Scope</name> <t>This document presents a common "grouping" statement for basic TCP connection parameters that matter to applications. It is "common" in that this grouping is used by both the "ietf-tcp-client" and "ietf-tcp-server" modules. In some TCP stacks, such parameters can also directly be set by an application using system calls, such as the sockets API. The base YANG data model in this document focuses on modeling TCP keep-alives. This base model can be extended as needed.</t> </section> <section anchor="common-features" toc="exclude"> <name>Features</name> <t>The following diagram lists all the "feature" statements defined in the "ietf-tcp-common" module:</t><artwork><![CDATA[<sourcecode type="yangtree"><![CDATA[ Features: +-- keepalives-supported]]></artwork>]]></sourcecode> <!--<aside>--> <t>The diagram above uses syntax that is similar to but not defined in <xref target="RFC8340"/>.</t> <!--</aside>--> </section> <section toc="exclude"> <name>Groupings</name> <t>The "ietf-tcp-common" module defines the following "grouping" statement:</t> <ul spacing="compact"> <li>tcp-common-grouping</li> </ul> <t>This grouping is presented in the following subsection.</t> <section anchor="tcp-common-grouping"> <name>The "tcp-common-grouping" Grouping</name> <t>The following tree diagram <xref target="RFC8340"/> illustrates the "tcp-common-grouping" grouping:</t><artwork><![CDATA[<sourcecode type="yangtree"><![CDATA[ grouping tcp-common-grouping: +-- keepalives! {keepalives-supported}? +-- idle-time? uint16 +-- max-probes? uint16 +-- probe-interval? uint16]]></artwork>]]></sourcecode> <t>Comments:</t> <ul> <li>The "keepalives" node is a "presence" container so that the mandatory descendant nodes do not imply thatkeepaliveskeep-alives must be configured.</li> <li>The "idle-time", "max-probes", and "probe-interval" nodes have the common meanings. Please see the YANG module in <xref target="common-yang-module"/> for details.</li> </ul> </section> </section> <section toc="exclude"><name>Protocol-accessible<name>Protocol-Accessible Nodes</name> <t>The "ietf-tcp-common" module defines only "grouping" statements that are used by other modules to instantiate protocol-accessible nodes.ThusThus, this module, when implemented, does not itself define any protocol-accessible nodes.</t> </section> <section toc="exclude"> <name>Guidelines for Configuring TCP Keep-Alives</name> <t>Network stacks may include"keep-alives"keep-alives in their TCP implementations, although this practice is not universally implemented. If keep-alives are included, <xref target="RFC9293"/> mandates that the applicationMUST<bcp14>MUST</bcp14> be able to turn them on or off for each TCPconnection,connection and that theyMUST<bcp14>MUST</bcp14> default to off.</t> <t>Keep-alive mechanisms exist in many protocols. Depending on the protocol stack, TCP keep-alives may only be one out of several alternatives. Which mechanism(s) to use depends on the use case and application requirements. If keep-alives are needed by an application, it isRECOMMENDED<bcp14>RECOMMENDED</bcp14> that the liveness check happens only at the protocol layers that are meaningful to the application.</t> <t>A TCP keep-alive mechanismSHOULD<bcp14>SHOULD</bcp14> only be invoked in server applications that might otherwise hang indefinitely and consume resources unnecessarily if a client crashes or aborts a connection during a network failure <xref target="RFC9293"/>. TCP keep-alives may consume significant resources both in the network and in endpoints (e.g., battery power). In addition, frequent keep-alives risk network congestion. The higher the frequency of keep-alives, the higher the overhead.</t> <t> Given the cost of keep-alives, parameters have to be configured carefully: </t> <ul spacing="normal"> <li>The default idle interval (leaf "idle-time") is two hours, i.e., 7200 seconds <xref target="RFC9293"/>. A lower valueMAY<bcp14>MAY</bcp14> be configured, but idle intervalsSHOULD NOT<bcp14>SHOULD NOT</bcp14> be smaller than 15 seconds. Longer idle intervalsSHOULD<bcp14>SHOULD</bcp14> be used when possible.</li> <li>The maximum number of sequential keep-alive probes that can fail (leaf "max-probes") trades off responsiveness and robustness against packet loss. ACK segments that contain no data are not reliably transmitted by TCP. Consequently, if a keep-alive mechanism isimplementedimplemented, itMUST NOT<bcp14>MUST NOT</bcp14> interpret failure to respond to any specific probe as a dead connection <xref target="RFC9293"/>. Typically, a single-digit number should suffice.</li> <li>TCP implementations may include a parameter for the number of seconds between TCP keep-alive probes (leaf "probe-interval"). In order to avoid congestion, the time interval between probesMUST NOT<bcp14>MUST NOT</bcp14> be smaller than one second. Significantly longer intervalsSHOULD<bcp14>SHOULD</bcp14> be used. It is important to note that keep-alive probes (or replies) can get dropped due to network congestion. Sending further probe messages into a congested path after a short interval, without backing off timers, could cause harm and result in a congestion collapse.ThereforeTherefore, it is essential to pick a large, conservative value for this interval.</li> </ul> </section> </section> <section anchor="common-examples"> <name>Example Usage</name> <t>This section presents an example showing the "tcp-common-grouping" grouping populated with some data.</t><artwork><![CDATA[<sourcecode type="xml"><![CDATA[ <!-- The outermost element below doesn't exist in the data model. --> <!-- It simulates if the "grouping" were a "container" instead. --> <tcp-common xmlns="urn:ietf:params:xml:ns:yang:ietf-tcp-common"> <keepalives> <idle-time>7200</idle-time> <max-probes>9</max-probes> <probe-interval>75</probe-interval> </keepalives> </tcp-common>]]></artwork>]]></sourcecode> </section> <section anchor="common-yang-module"> <name>YANG Module</name> <t>Theietf-tcp-common"ietf-tcp-common" YANG module references <xref target="RFC6991"/> and <xref target="RFC9293"/>.</t><t keepWithNext="true"><CODE BEGINS> file "ietf-tcp-common@2024-04-04.yang"</t> <artwork><![CDATA[<!--[rfced] FYI, a few minor updates were made to the YANG module ietf-tcp-common to match the formatted output of pyang. --> <sourcecode name="ietf-tcp-common@2024-04-04.yang" type="yang" markers="true"><![CDATA[ module ietf-tcp-common { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-tcp-common"; prefix tcpcmn; organization "IETF NETCONF (Network Configuration) Working Group and the IETF TCP Maintenance and Minor Extensions (TCPM) Working Group"; contact "WG Web: https://datatracker.ietf.org/wg/netconf https://datatracker.ietf.org/wg/tcpm WG List: NETCONF WG list <mailto:netconf@ietf.org> TCPM WG list <mailto:tcpm@ietf.org> Authors: Kent Watsen <mailto:kent+ietf@watsen.net> Michael Scharf <mailto:michael.scharf@hs-esslingen.de>"; description "This module define a reusable 'grouping' that is common to bothTCP-clientsTCP clients andTCP-servers.TCP servers. This grouping statement is used by both the 'ietf-tcp-client' and 'ietf-tcp-server' modules. 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 (RFC 2119) (RFC 8174) when, and only when, they appear in all capitals, as shown here. Copyright (c)20232024 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 Revised BSD License set forth in Section 4.c of the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info). This version of this YANG module is part of RFCDDDD (https://www.rfc-editor.org/info/rfcDDDD);9643 (https://www.rfc-editor.org/info/rfc9643); see the RFC itself for full legalnotices. 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 (RFC 2119) (RFC 8174) when, and only when, they appear in all capitals, as shown here.";notices."; revision 2024-04-04 { description "Initialversion";version."; reference "RFCDDDD:9643: YANG Groupings for TCP Clients and TCP Servers"; } // Features feature keepalives-supported { description "Indicates that keepalives are supported."; } // Groupings grouping tcp-common-grouping { description "A reusable grouping for configuring TCP parameters common to TCP connections as well as the operating system as a whole."; container keepalives { if-feature "keepalives-supported"; presence "Indicates that keepalives are enabled, aligning to the requirement in Section 3.8.4 of RFC 9293 that states keepalives are off by default."; description "Configures thekeep-alive policy,keepalive policy to proactively test the aliveness of the TCP peer. An unresponsive TCP peer is dropped after approximately (idle-time + max-probes * probe-interval) seconds. Further guidance can be found in Section 2.1.5 of RFCDDDD.";9643."; reference "RFC 9293: Transmission Control Protocol (TCP)"; leaf idle-time { type uint16 { range "1..max"; } units "seconds"; default7200;"7200"; description "Sets the amount of time after whichif no data has been received from the TCP peer,a TCP-level probe message will be sent to test the aliveness of the TCP peer if no data has been received from the TCP peer. Two hours (7200 seconds) is a safe value, perRFC 9293Section3.8.4.";3.8.4 of RFC 9293."; reference "RFC 9293: Transmission Control Protocol (TCP)"; } leaf max-probes { type uint16 { range "1..max"; } default9;"9"; description "Sets the maximum number of sequentialkeep-alivekeepalive probes that can fail to obtain a response from the TCP peer before assuming the TCP peer is no longer alive."; } leaf probe-interval { type uint16 { range "1..max"; } units "seconds"; default75;"75"; description "Sets the time interval between failed probes. The interval SHOULD be significantly longer than one second in order to avoid harm on a congested link."; } } // container keepalives } // grouping tcp-common-grouping }]]></artwork> <t keepWithPrevious="true"><CODE ENDS></t>]]></sourcecode> </section> </section> <section anchor="tcp-client-model"> <name>The "ietf-tcp-client" Module</name> <t>This section defines a YANG 1.1 module called "ietf-tcp-client". A high-level overview of the module is provided in <xref target="client-overview"/>. Examples illustrating the module's use are provided in <xreftarget="client-examples">Examples</xref>.target="client-examples"/> ("Example Usage"). The YANG module itself is defined in <xref target="client-yang-module"/>.</t> <section anchor="client-overview"> <name>Data Model Overview</name> <t>This section provides an overview of the "ietf-tcp-client" module in terms of its features and groupings.</t> <section anchor="features" toc="exclude"> <name>Features</name> <t>The following diagram lists all the "feature" statements defined in the "ietf-tcp-client" module:</t><artwork><![CDATA[<sourcecode type="yangtree"><![CDATA[ Features: +-- local-binding-supported +-- tcp-client-keepalives +-- proxy-connect +-- socks4-supported {proxy-connect}? +-- socks4a-supported {proxy-connect}? +-- socks5-supported {proxy-connect}? +-- socks5-gss-api {socks5-supported}? +-- socks5-username-password {socks5-supported}?]]></artwork>]]></sourcecode> <t>Comments:</t> <ul> <li>The "local-binding-supported" feature indicates that the server supports configuring local bindings (i.e., the local address and local port) for TCPclients."</li>clients.</li> <li>The "tcp-client-keepalives" feature indicates that per socket TCP keepalive parameters are configurable for TCP clients on the server implementing this feature.</li> <li>The "proxy-connect" feature indicates theTCP-clientTCP client supports connecting through TCP proxies.</li> <li>The "socks4-supported" feature indicates theTCP-clientTCP client supports Socks4-based proxies.</li> <li>The "socks4a-supported" feature indicates theTCP-clientTCP client supports Socks4a-based proxies. The difference between Socks4 and Socks4a is that Socks4a enables the "remote-address" to be specified using a hostname, in addition to an IP address.</li> <li>The "socks5-supported" feature indicates theTCP-clientTCP client supports Socks5-based proxies.</li> <li>The "socks5-gss-api" feature indicates that the server, when acting as aTCP-client,TCP client, supports authenticating to a SOCKS Version 5 proxy server usingGSSAPIGeneric Security Service Application Program Interface (GSS-API) credentials.</li> <li>The "socks5-username-password" feature indicates that the server, when acting as aTCP-client,TCP client, supports authenticating to a SOCKS Version 5 proxy server using'username'"username" and'password'"password" credentials."</li> </ul> <!--<aside>--> <t>The diagram above uses syntax that is similar to but not defined in <xref target="RFC8340"/>.</t> <!--</aside>--> </section> <section toc="exclude"> <name>Groupings</name> <t>The "ietf-tcp-client" module defines the following "grouping" statement:</t> <ul spacing="compact"> <li>tcp-client-grouping</li> </ul> <t>This grouping is presented in the following subsection.</t> <section anchor="tcp-client-grouping"> <name>The "tcp-client-grouping" Grouping</name> <t>The following tree diagram <xref target="RFC8340"/> illustrates the "tcp-client-grouping" grouping:</t><artwork><![CDATA[<sourcecode type="yangtree"><![CDATA[ grouping tcp-client-grouping: +-- remote-address inet:host +-- remote-port? inet:port-number +-- local-address? inet:ip-address | {local-binding-supported}? +-- local-port? inet:port-number | {local-binding-supported}? +-- proxy-server! {proxy-connect}? | +-- (proxy-type) | +--:(socks4) {socks4-supported}? | | +-- socks4-parameters | | +-- remote-address inet:ip-address | | +-- remote-port? inet:port-number | +--:(socks4a) {socks4a-supported}? | | +-- socks4a-parameters | | +-- remote-address inet:host | | +-- remote-port? inet:port-number | +--:(socks5) {socks5-supported}? | +-- socks5-parameters | +-- remote-address inet:host | +-- remote-port? inet:port-number | +-- authentication-parameters! | +-- (auth-type) | +--:(gss-api) {socks5-gss-api}? | | +-- gss-api | +--:(username-password) | {socks5-username-password}? | +-- username-password | +-- username string | +---u ct:password-grouping +---u tcpcmn:tcp-common-grouping]]></artwork>]]></sourcecode> <t>Comments:</t> <ul> <li>The "remote-address" node, which is mandatory, may be configured as an IPv4 address, an IPv6 address, or a hostname.</li> <li>The "remote-port" node is not mandatory, but its default value is the invalid value'0',"0", thus forcing the consuming data model to refine it in order to provide it an appropriate default value.</li> <!--[rfced] We note that "local-binding-supported" is not mentioned in Section 2.1.2. Please review and let us know if updates are needed. Original: * The "local-address" node, which is enabled by the "local-binding- supported" feature (Section 2.1.2), may be configured as an IPv4 address, an IPv6 address, or a wildcard value. * The "local-port" node, which is enabled by the "local-binding- supported" feature (Section 2.1.2), is not mandatory. Its default value is '0', indicating that the operating system can pick an arbitrary port number. --> <li>The "local-address" node, which is enabled by the "local-binding-supported" feature (<xref target="common-features"/>), may be configured as an IPv4 address, an IPv6 address, or a wildcard value.</li> <li>The "local-port" node, which is enabled by the "local-binding-supported" feature (<xref target="common-features"/>), is not mandatory. Its default value is'0',"0", indicating that the operating system can pick an arbitrary port number.</li> <li>The "proxy-server" node is enabled by a "feature" statement and, for servers that enable it, is a "presence" container so that the descendant "mandatory true" choice node does not imply that the proxy-server node must be configured. The proxy-server node uses a "choice" statement to allow one of several types of proxies to be configured. The choices presented in this document include Socks4, Socks4a, and Socks5, each enabled by a YANG feature (see <xref target="features"/>). Other proxy types may be added by future work.</li> <li>This grouping uses the "password-grouping" grouping discussed in <xreftarget="I-D.ietf-netconf-crypto-types"/>.</li>target="RFC9640"/>.</li> <li>This grouping uses the "tcp-common-grouping" grouping discussed in <xref target="tcp-common-grouping"/>.</li> </ul> </section> </section> <section toc="exclude"><name>Protocol-accessible<name>Protocol-Accessible Nodes</name> <t>The "ietf-tcp-client" module defines only "grouping" statements that are used by other modules to instantiate protocol-accessible nodes.ThusThus, this module, when implemented, does not itself define any protocol-accessible nodes.</t> </section> </section> <section anchor="client-examples"> <name>Example Usage</name> <t>This section presents two examples showing the "tcp-client-grouping" grouping populated with some data. This example shows aTCP-clientTCP client configured to not connect via a proxy:</t><artwork><![CDATA[<sourcecode type="xml"><![CDATA[ <!-- The outermost element below doesn't exist in the data model. --> <!-- It simulates if the "grouping" were a "container" instead. --> <tcp-client xmlns="urn:ietf:params:xml:ns:yang:ietf-tcp-client"> <remote-address>www.example.com</remote-address> <remote-port>8443</remote-port> <local-address>192.0.2.2</local-address> <local-port>12345</local-port> <keepalives> <idle-time>7200</idle-time> <max-probes>9</max-probes> <probe-interval>75</probe-interval> </keepalives> </tcp-client>]]></artwork>]]></sourcecode> <t>This example shows aTCP-clientTCP client configured to connect via a proxy:</t><artwork><![CDATA[<sourcecode type="xml"><![CDATA[ <!-- The outermost element below doesn't exist in the data model. --> <!-- It simulates if the "grouping" were a "container" instead. --> <tcp-client xmlns="urn:ietf:params:xml:ns:yang:ietf-tcp-client"> <remote-address>www.example.com</remote-address> <remote-port>8443</remote-port> <local-address>192.0.2.2</local-address> <local-port>12345</local-port> <proxy-server> <socks5-parameters> <remote-address>proxy.example.com</remote-address> <remote-port>1080</remote-port> <authentication-parameters> <username-password> <username>foobar</username> <cleartext-password>secret</cleartext-password> </username-password> </authentication-parameters> </socks5-parameters> </proxy-server> <keepalives> <idle-time>7200</idle-time> <max-probes>9</max-probes> <probe-interval>75</probe-interval> </keepalives> </tcp-client>]]></artwork>]]></sourcecode> </section> <section anchor="client-yang-module"> <name>YANG Module</name> <t>Theietf-tcp-client"ietf-tcp-client" YANG module references <xref target="SOCKS_4A"/>, <xref target="RFC1928"/>, <xref target="RFC1929"/>, <xref target="RFC2743"/>, <xref target="RFC6991"/>, <xref target="RFC9293"/>, and <xreftarget="I-D.ietf-netconf-crypto-types"/>.</t> <t keepWithNext="true"><CODE BEGINS> file "ietf-tcp-client@2024-04-04.yang"</t> <artwork><![CDATA[target="RFC9640"/>.</t> <!--[rfced] FYI, a few minor updates were made to the YANG module ietf-tcp-client to match the formatted output of pyang. --> <!--[rfced] We note that the 2119/8174 keywords do not appear in the "ietf-tcp-client" and "ietf-tcp-server" YANG modules, but both modules include paragraphs that explain how the terms are to be interpreted. Should these paragraphs be removed? --> <!--[rfced] We note that the following reference only appears in the "ietf-tcp-client" YANG module. Should it be mentioned in the general statement preceding the module (i.e., "The "ietf-tcp-client" YANG module references..."? Should a reference entry for it be added to the References section? SOCKS Proceedings: 1992 Usenix Security Symposium --> <sourcecode name="ietf-tcp-client@2024-04-04.yang" type="yang" markers="true"><![CDATA[ module ietf-tcp-client { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-tcp-client"; prefix tcpc; import ietf-inet-types { prefix inet; reference "RFC 6991: Common YANG Data Types"; } import ietf-crypto-types { prefix ct; reference "RFCAAAA:9640: YANG Data Types and Groupings for Cryptography"; } import ietf-tcp-common { prefix tcpcmn; reference "RFCDDDD:9643: YANG Groupings for TCP Clients and TCP Servers"; } organization "IETF NETCONF (Network Configuration) Working Group and the IETF TCP Maintenance and Minor Extensions (TCPM) Working Group"; contact "WG Web: https://datatracker.ietf.org/wg/netconf https://datatracker.ietf.org/wg/tcpm WG List: NETCONF WG list <mailto:netconf@ietf.org> TCPM WG list <mailto:tcpm@ietf.org> Authors: Kent Watsen <mailto:kent+ietf@watsen.net> Michael Scharf <mailto:michael.scharf@hs-esslingen.de>"; description "This module defines reusable groupings for TCP clients that can be used as a basis for specific TCP client instances. 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 (RFC 2119) (RFC 8174) when, and only when, they appear in all capitals, as shown here. Copyright (c) 2024 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 Revised BSD License set forth in Section 4.c of the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info). This version of this YANG module is part of RFCDDDD (https://www.rfc-editor.org/info/rfcDDDD);9643 (https://www.rfc-editor.org/info/rfc9643); see the RFC itself for full legalnotices. 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 (RFC 2119) (RFC 8174) when, and only when, they appear in all capitals, as shown here.";notices."; revision 2024-04-04 { description "Initialversion";version."; reference "RFCDDDD:9643: YANG Groupings for TCP Clients and TCP Servers"; } // Features feature local-binding-supported { description "Indicates that the server supports configuring local bindings (i.e., the local address and local port) for TCP clients."; } feature tcp-client-keepalives { description "Per socket TCP keepalive parameters are configurable for TCP clients on the server implementing this feature."; reference "RFC 9293: Transmission Control Protocol (TCP)"; } feature proxy-connect { description "Indicates theTCP-clientTCP client supports connecting through TCP proxies."; } feature socks4-supported { if-featureproxy-connect;"proxy-connect"; description "Indicates theTCP-clientTCP client supports Socks4-based proxies."; reference "SOCKS Proceedings: 1992 Usenix SecuritySymposium.";Symposium"; } feature socks4a-supported { if-featureproxy-connect;"proxy-connect"; description "Indicates theTCP-clientTCP client supports Socks4a-based proxies."; reference "OpenSSH message: SOCKS 4A: A Simple Extension to SOCKS 4 Protocolhttps://www.openssh.com/txt/socks4a.protocol.";<https://www.openssh.com/txt/socks4a.protocol>"; } feature socks5-supported { if-featureproxy-connect;"proxy-connect"; description "Indicates theTCP-clientTCP client supports Socks5-based proxies."; reference "RFC 1928: SOCKS Protocol Version 5"; } feature socks5-gss-api { if-featuresocks5-supported;"socks5-supported"; description "Indicates that the server, when acting as aTCP-client,TCP client, supports authenticating to a SOCKS Version 5 proxy server usingGSSAPIGSS-API credentials."; reference "RFC 1928: SOCKS Protocol Version 5"; } feature socks5-username-password { if-featuresocks5-supported;"socks5-supported"; description "Indicates that the server, when acting as aTCP-client,TCP client, supports authenticating to a SOCKS Version 5 proxy server using 'username' and 'password' credentials."; reference "RFC 1928: SOCKS Protocol Version 5"; } // Groupings grouping tcp-client-grouping { description "A reusable grouping for configuring a TCP client. Note that this grouping uses fairly typical descendant node names such that a stack of 'uses' statements will have name conflicts. It is intended that the consuming data model will resolve the issue (e.g., by wrapping the 'uses' statement in a container called 'tcp-client-parameters'). This model purposely does not do this itself so as to provide maximum flexibility to consuming models."; leaf remote-address { type inet:host; mandatory true; description "The IP address or hostname of the remote peer to establish a connection with. If a domain name is configured, then the DNS resolution should happen on each connection attempt. If the DNS resolution results in multiple IP addresses, the IP addresses are tried according to local preference order until a connection has been established or until all IP addresses have failed."; } leaf remote-port { type inet:port-number; default "0"; description "The IP port number for the remote peer to establish a connection with. An invalid default value is used so that importing modules may 'refine' it with the appropriate default port number value."; } leaf local-address { if-feature "local-binding-supported"; type inet:ip-address; description "The local IP address/interface to bind to for when connecting to the remote peer. INADDR_ANY ('0.0.0.0') or INADDR6_ANY ('0:0:0:0:0:0:0:0' a.k.a. '::') MAY be used to explicitly indicate the implicit default,thatwhich the server can bind to any IPv4 or IPv6 address."; } leaf local-port { if-feature "local-binding-supported"; type inet:port-number; default "0"; description "The local IP port number to bind to for when connecting to the remote peer. The port number '0', which is the default value, indicates that any available local port number may be used."; } container proxy-server { if-feature "proxy-connect"; presence "Indicates that a proxy connection has been configured. Present so that the mandatory descendant nodes do not imply that this node must be configured."; choice proxy-type { mandatory true; description "Selects a proxy connection protocol."; case socks4 { if-featuresocks4-supported;"socks4-supported"; container socks4-parameters { leaf remote-address { type inet:ip-address; mandatory true; description "The IP address of the proxy server."; } leaf remote-port { type inet:port-number; default "1080"; description "The IP port number for the proxy server."; } description "Parameters for connecting to a TCP-based proxy server using the SOCKS4 protocol."; reference"SOCKS,"SOCKS Proceedings: 1992 Usenix SecuritySymposium.";Symposium"; } } case socks4a { if-featuresocks4a-supported;"socks4a-supported"; container socks4a-parameters { leaf remote-address { type inet:host; mandatory true; description "The IP address or hostname of the proxy server."; } leaf remote-port { type inet:port-number; default "1080"; description "The IP port number for the proxy server."; } description "Parameters for connecting to a TCP-based proxy server using the SOCKS4a protocol."; reference "SOCKS Proceedings: 1992 Usenix SecuritySymposium.Symposium OpenSSH message: SOCKS 4A: A Simple Extension to SOCKS 4 Protocolhttps://www.openssh.com/txt/socks4a.protocol";<https://www.openssh.com/txt/socks4a.protocol>"; } } case socks5 { if-featuresocks5-supported;"socks5-supported"; container socks5-parameters { leaf remote-address { type inet:host; mandatory true; description "The IP address or hostname of the proxy server."; } leaf remote-port { type inet:port-number; default "1080"; description "The IP port number for the proxy server."; } container authentication-parameters { presence "Indicates that an authentication mechanism has been configured. Present so that the mandatory descendant nodes do not imply that this node must be configured."; description "A container for SOCKS Version 5 authentication mechanisms. A complete list of methods is defined at:https://www.iana.org/assignments/socks-methods /socks-methods.xhtml.";<https://www.iana.org/assignments/socks-methods>."; reference "RFC 1928: SOCKS Protocol Version 5"; choice auth-type { mandatory true; description "A choice amongst supported SOCKS Version 5 authentication mechanisms."; case gss-api { if-feature "socks5-gss-api"; container gss-api { description "Contains GSS-API configuration. Defines as an empty container to enable specific GSS-API configuration to be augmented in by future modules."; reference "RFC 1928: SOCKS Protocol Version 5 RFC 2743: Generic Security Service Application Program Interface Version 2, Update 1"; } } case username-password { if-feature "socks5-username-password"; container username-password { leaf username { type string; mandatory true; description "The 'username' value to use for client identification."; } uses ct:password-grouping { description "The password to be used for client authentication."; } description "ContainsUsername/Passwordusername/password configuration."; reference "RFC 1929: Username/Password Authentication for SOCKS V5"; } } } } description "Parameters for connecting to a TCP-based proxy server using the SOCKS5 protocol."; reference "RFC 1928: SOCKS Protocol Version 5"; } } } description "Proxy server settings."; } uses tcpcmn:tcp-common-grouping { refine "keepalives" { if-feature "tcp-client-keepalives"; description "Anif-feature'if-feature' statement so that implementations can choose to support TCP client keepalives."; } } } }]]></artwork> <t keepWithPrevious="true"><CODE ENDS></t>]]></sourcecode> </section> </section> <section anchor="tcp-server-model"> <name>The "ietf-tcp-server" Module</name> <t>This section defines a YANG 1.1 module called "ietf-tcp-server". A high-level overview of the module is provided in <xref target="server-overview"/>. Examples illustrating the module's use are provided in <xreftarget="server-examples">Examples</xref>.target="server-examples"/> ("Example Usage"). The YANG module itself is defined in <xref target="server-yang-module"/>.</t> <section anchor="server-overview"> <name>Data Model Overview</name> <t>This section provides an overview of the "ietf-tcp-server" module in terms of its features and groupings.</t> <section toc="exclude"> <name>Features</name> <t>The following diagram lists all the "feature" statements defined in the "ietf-tcp-server" module:</t><artwork><![CDATA[<sourcecode type="yangtree"><![CDATA[ Features: +-- tcp-server-keepalives]]></artwork>]]></sourcecode> <!--<aside>--> <t>The diagram above uses syntax that is similar to but not defined in <xref target="RFC8340"/>.</t> <!--</aside>--> </section> <section toc="exclude"> <name>Groupings</name> <t>The "ietf-tcp-server" module defines the following "grouping" statement:</t> <ul spacing="compact"> <li>tcp-server-grouping</li> </ul> <t>This grouping is presented in the following subsection.</t> <section anchor="tcp-server-grouping"> <name>The "tcp-server-grouping" Grouping</name> <t>The following tree diagram <xref target="RFC8340"/> illustrates the "tcp-server-grouping" grouping:</t><artwork><![CDATA[<sourcecode type="yangtree"><![CDATA[ grouping tcp-server-grouping: +-- local-bind* [local-address] | +-- local-address? inet:ip-address | +-- local-port? inet:port-number +---u tcpcmn:tcp-common-grouping]]></artwork>]]></sourcecode> <t>Comments:</t> <ul> <li>The "local-address" node, which is mandatory, may be configured as an IPv4 address, an IPv6 address, or a wildcard value.</li> <li>The "local-port" node is not mandatory, but its default value is the invalid value'0',"0", thus forcing the consuming data model to refine it in order to provide it an appropriate default value.</li> <li>This grouping uses the "tcp-common-grouping" grouping discussed in <xref target="tcp-common-grouping"/>.</li> </ul> </section> </section> <section toc="exclude"><name>Protocol-accessible<name>Protocol-Accessible Nodes</name> <t>The "ietf-tcp-server" module defines only "grouping" statements that are used by other modules to instantiate protocol-accessible nodes.ThusThus, this module, when implemented, does not itself define any protocol-accessible nodes.</t> </section> </section> <section anchor="server-examples"> <name>Example Usage</name> <t>This section presents an example showing the "tcp-server-grouping" grouping populated with some data.</t><artwork><![CDATA[<sourcecode type="xml"><![CDATA[ <!-- The outermost element below doesn't exist in the data model. --> <!-- It simulates if the "grouping" were a "container" instead. --> <tcp-server xmlns="urn:ietf:params:xml:ns:yang:ietf-tcp-server"> <local-bind> <local-address>192.0.2.2</local-address> <local-port>49152</local-port> </local-bind> <keepalives> <idle-time>7200</idle-time> <max-probes>9</max-probes> <probe-interval>75</probe-interval> </keepalives> </tcp-server>]]></artwork>]]></sourcecode> </section> <section anchor="server-yang-module"> <name>YANG Module</name> <t>Theietf-tcp-server"ietf-tcp-server" YANG module references <xref target="RFC6991"/> and <xref target="RFC9293"/>.</t><t keepWithNext="true"><CODE BEGINS> file "ietf-tcp-server@2024-04-04.yang"</t> <artwork><![CDATA[<!--[rfced] FYI, a minor update was made to the YANG module ietf-tcp-server to match the formatted output of pyang. --> <sourcecode name="ietf-tcp-server@2024-04-04.yang" type="yang" markers="true"><![CDATA[ module ietf-tcp-server { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-tcp-server"; prefix tcps; import ietf-inet-types { prefix inet; reference "RFC 6991: Common YANG Data Types"; } import ietf-tcp-common { prefix tcpcmn; reference "RFCDDDD:9643: YANG Groupings for TCP Clients and TCP Servers"; } organization "IETF NETCONF (Network Configuration) Working Group and the IETF TCP Maintenance and Minor Extensions (TCPM) Working Group"; contact "WG Web: https://datatracker.ietf.org/wg/netconf https://datatracker.ietf.org/wg/tcpm WG List: NETCONF WG list <mailto:netconf@ietf.org> TCPM WG list <mailto:tcpm@ietf.org> Authors: Kent Watsen <mailto:kent+ietf@watsen.net> Michael Scharf <mailto:michael.scharf@hs-esslingen.de>"; description "This module defines reusable groupings for TCP servers that can be used as a basis for specific TCP server instances. 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 (RFC 2119) (RFC 8174) when, and only when, they appear in all capitals, as shown here. Copyright (c) 2024 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 Revised BSD License set forth in Section 4.c of the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/license-info). This version of this YANG module is part of RFCDDDD (https://www.rfc-editor.org/info/rfcDDDD);9643 (https://www.rfc-editor.org/info/rfc9643); see the RFC itself for full legalnotices. 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 (RFC 2119) (RFC 8174) when, and only when, they appear in all capitals, as shown here.";notices."; revision 2024-04-04 { description "Initialversion";version."; reference "RFCDDDD:9643: YANG Groupings for TCP Clients and TCP Servers"; } // Features feature tcp-server-keepalives { description "Per socket TCP keepalive parameters are configurable for TCP servers on the server implementing this feature."; reference "RFC 9293: Transmission Control Protocol (TCP)"; } // Groupings grouping tcp-server-grouping { description "A reusable grouping for configuring a TCP server. Note that this grouping uses fairly typical descendant node names such that a stack of 'uses' statements will have name conflicts. It is intended that the consuming data model will resolve the issue (e.g., by wrapping the 'uses' statement in a container called 'tcp-server-parameters'). This model purposely does not do this itself so as to provide maximum flexibility to consuming models."; list local-bind { keylocal-address;"local-address"; min-elements 1; description "A list of bind (listen) points for this server instance. A server instance may have multiple bind points to support, e.g., the same port in different address families or different ports in the same address family."; leaf local-address { type inet:ip-address; description "The local IP address to listen on for incoming TCP client connections. To configure listening on all IPv4addressesaddresses, the value must be '0.0.0.0' (INADDR_ANY). To configure listening on all IPv6addressesaddresses, the value must be '::' (INADDR6_ANY)."; } leaf local-port { type inet:port-number; default "0"; description "The local port number to listen on for incoming TCP client connections. An invalid default value (0) is used (instead of 'mandatory true') so that anapplication levelapplication-level data model may 'refine' it with anapplication specificapplication-specific default port number value."; } } uses tcpcmn:tcp-common-grouping { refine "keepalives" { if-feature "tcp-server-keepalives"; description "Anif-feature'if-feature' statement so that implementations can choose to support TCP server keepalives."; } } } }]]></artwork> <t keepWithPrevious="true"><CODE ENDS></t>]]></sourcecode> </section> </section> <section> <name>Security Considerations</name> <t>The three YANG modules in this document define groupings and will not be deployed as standalone modules. Their security implications may becontext dependentcontext-dependent based on their use in other modules. The designers of moduleswhichthat import thesegroupinggroupings must conduct their own analysis of the security considerations.</t> <section> <!--[rfced] *AD - We note that the text in Sections 5.1-5.3 do not exactly match the YANG security considerations boilerplate text at <https://wiki.ietf.org/group/ops/yang-security-guidelines>, including missing citations to RFCs 6242 and 8446. Please review and let us know if the text requires any updates. --> <name>Considerations for the "ietf-tcp-common" YANG Module</name> <t>This section follows the template defined in <xref section="3.7.1" sectionFormat="of" target="RFC8407"/>.</t> <t>The "ietf-tcp-common" YANG module defines "grouping" statements that are designed to be accessed viaYANG basedYANG-based management protocols, such as NETCONF <xref target="RFC6241"/> and RESTCONF <xref target="RFC8040"/>. Both of these protocols have mandatory-to-implement secure transport layers (e.g.,SSH,Secure Shell (SSH), TLS) with mutual authentication.</t> <t>The Network Configuration Access Control Model (NACM) <xref target="RFC8341"/> provides the means to restrict access for particular users to apre-configuredpreconfigured subset of all available protocol operations and content.</t> <t>Please be aware that this YANG module uses groupings from other YANG modules that define nodes that may be considered sensitive or vulnerable in network environments. Please review theSecurity Considerationssecurity considerations for dependent YANG modules for information as to which nodes may be considered sensitive or vulnerable in network environments.</t> <t>None of the readable data nodes defined in this YANG module are considered sensitive or vulnerable in network environments. The NACM "default-deny-all" extension has not been set for any data nodes defined in this module.</t> <t>None of the writable data nodes defined in this YANG module are considered sensitive or vulnerable in network environments. The NACM "default-deny-write" extension has not been set for any data nodes defined in this module.</t> <t>This module does not define any RPCs, actions, or notifications, andthusthus, the securityconsiderationconsiderations for suchisare not provided here.</t> </section> <section> <name>Considerations for the "ietf-tcp-client" YANG Module</name> <t>This section follows the template defined in <xref section="3.7.1" sectionFormat="of" target="RFC8407"/>.</t> <t>The "ietf-tcp-client" YANG module defines "grouping" statements that are designed to be accessed viaYANG basedYANG-based management protocols, such as NETCONF <xref target="RFC6241"/> and RESTCONF <xref target="RFC8040"/>. Both of these protocols have mandatory-to-implement secure transport layers (e.g., SSH, TLS) with mutual authentication.</t> <t>The Network Configuration Access Control Model (NACM) <xref target="RFC8341"/> provides the means to restrict access for particular users to apre-configuredpreconfigured subset of all available protocol operations and content.</t> <t>Please be aware that this YANG module uses groupings from other YANG modules that define nodes that may be considered sensitive or vulnerable in network environments. Please review theSecurity Considerationssecurity considerations for dependent YANG modules for information as to which nodes may be considered sensitive or vulnerable in network environments.</t> <t>One readable data node defined in this YANG module may be considered sensitive or vulnerable in some network environments. This node is as follows: </t> <ul spacing="normal"> <li> <t>The "proxy-server/socks5-parameters/authentication-parameters/username-password/password" node: </t> <ul empty="true"> <li>The "password" node defined in the "tcp-client-grouping" grouping is defined using the "password-grouping" grouping presented in <xreftarget="I-D.ietf-netconf-crypto-types"/>.target="RFC9640"/>. This grouping enables both cleartext and encrypted passwords to be configured. As the referenced document states, configuration of cleartext passwords isNOT RECOMMENDED.<bcp14>NOT RECOMMENDED</bcp14>. However, in the case cleartext values are configured, this node is additionally sensitive to read operations such that, in normal use cases, it should never be returned to a client. For this reason, the NACMextension"default-deny-all" extension has been applied to it.</li> </ul> </li> </ul> <t>None of the writable data nodes defined in this YANG module are considered sensitive or vulnerable in network environments. The NACM "default-deny-write" extension has not been set for any data nodes defined in this module.</t> <t>This module does not define any RPCs, actions, or notifications, andthusthus, the securityconsiderationconsiderations for suchisare not provided here.</t> <t>Implementations areRECOMMENDED<bcp14>RECOMMENDED</bcp14> to implement the "local-binding-supported" feature forcryptographically-secure protocols,cryptographically secure protocols so as to enable more granular ingress/egress firewallrulebases.rule bases. It isNOT RECOMMENDED<bcp14>NOT RECOMMENDED</bcp14> to implement this feature for unsecure protocols, as per <xref target="RFC6056"/>.</t> </section> <section> <name>Considerations for the "ietf-tcp-server" YANG Module</name> <t>This section follows the template defined in <xref section="3.7.1" sectionFormat="of" target="RFC8407"/>.</t> <t>The "ietf-tcp-server" YANG module defines "grouping" statements that are designed to be accessed viaYANG basedYANG-based management protocols, such as NETCONF <xref target="RFC6241"/> and RESTCONF <xref target="RFC8040"/>. Both of these protocols have mandatory-to-implement secure transport layers (e.g., SSH, TLS) with mutual authentication.</t> <t>The Network Configuration Access Control Model (NACM) <xref target="RFC8341"/> provides the means to restrict access for particular users to apre-configuredpreconfigured subset of all available protocol operations and content.</t> <t>Please be aware that this YANG module uses groupings from other YANG modules that define nodes that may be considered sensitive or vulnerable in network environments. Please review theSecurity Considerationssecurity considerations for dependent YANG modules for information as to which nodes may be considered sensitive or vulnerable in network environments.</t> <t>None of the readable data nodes defined in this YANG module are considered sensitive or vulnerable in network environments. The NACM "default-deny-all" extension has not been set for any data nodes defined in this module.</t> <t>None of the writable data nodes defined in this YANG module are considered sensitive or vulnerable in network environments. The NACM "default-deny-write" extension has not been set for any data nodes defined in this module.</t> <t>This module does not define any RPCs, actions, or notifications, andthusthus, the securityconsiderationconsiderations for suchisare not provided here.</t> </section> </section> <section> <name>IANA Considerations</name> <section> <name>The"IETF XML"IETF XML Registry</name><t>This document registers three URIs<t>IANA has registered the following URI in the "ns"subregistryregistry of theIETF"IETF XMLRegistryRegistry" <xreftarget="RFC3688"/>. Following the format in <xref target="RFC3688"/>, the following registrations are requested:</t> <artwork><![CDATA[ URI: urn:ietf:params:xml:ns:yang:ietf-tcp-common Registrant Contact: The IESG XML:target="RFC3688"/>.</t> <!-- note for IANA: Please update comma to semicolon here. OLD: N/A, the requested URI is an XML namespace.URI: urn:ietf:params:xml:ns:yang:ietf-tcp-client Registrant Contact: The IESG XML: N/A,NEW: N/A; the requested URI is an XML namespace.URI: urn:ietf:params:xml:ns:yang:ietf-tcp-server Registrant Contact: The IESG XML: N/A,--> <dl newline="false" spacing="compact"> <dt>URI:</dt> <dd>urn:ietf:params:xml:ns:yang:ietf-tcp-common</dd> <dt>Registrant Contact:</dt> <dd>The IESG</dd> <dt>XML:</dt> <dd>N/A; the requested URI is an XMLnamespace. ]]></artwork>namespace.</dd> </dl> <dl newline="false" spacing="compact"> <dt>URI:</dt> <dd>urn:ietf:params:xml:ns:yang:ietf-tcp-client</dd> <dt>Registrant Contact:</dt> <dd>The IESG</dd> <dt>XML:</dt> <dd>N/A; the requested URI is an XML namespace.</dd> </dl> <dl newline="false" spacing="compact"> <dt>URI:</dt> <dd>urn:ietf:params:xml:ns:yang:ietf-tcp-server</dd> <dt>Registrant Contact:</dt> <dd>The IESG</dd> <dt>XML:</dt> <dd>N/A; the requested URI is an XML namespace.</dd> </dl> </section> <section> <name>The"YANGYANG ModuleNames"Names Registry</name><t>This document registers<t>IANA has registered the following three YANG modules in theYANG"YANG ModuleNamesNames" registry <xref target="RFC6020"/>.Following the format in <xref target="RFC6020"/>, the following registrations are requested:</t> <artwork><![CDATA[ name: ietf-tcp-common namespace: urn:ietf:params:xml:ns:yang:ietf-tcp-common prefix: tcpcmn reference: RFC DDDD name: ietf-tcp-client namespace: urn:ietf:params:xml:ns:yang:ietf-tcp-client prefix: tcpc reference: RFC DDDD name: ietf-tcp-server namespace: urn:ietf:params:xml:ns:yang:ietf-tcp-server prefix: tcps reference: RFC DDDD ]]></artwork></t> <dl newline="false" spacing="compact"> <dt>name:</dt> <dd>ietf-tcp-common</dd> <dt>namespace:</dt> <dd>urn:ietf:params:xml:ns:yang:ietf-tcp-common</dd> <dt>prefix:</dt> <dd>tcpcmn</dd> <dt>reference:</dt> <dd>RFC 9643</dd> </dl> <dl newline="false" spacing="compact"> <dt>name:</dt> <dd>ietf-tcp-client</dd> <dt>namespace:</dt> <dd>urn:ietf:params:xml:ns:yang:ietf-tcp-client</dd> <dt>prefix:</dt> <dd>tcpc</dd> <dt>reference:</dt> <dd>RFC 9643</dd> </dl> <dl newline="false" spacing="compact"> <dt>name:</dt> <dd>ietf-tcp-server</dd> <dt>namespace:</dt> <dd>urn:ietf:params:xml:ns:yang:ietf-tcp-server</dd> <dt>prefix:</dt> <dd>tcps</dd> <dt>reference:</dt> <dd>RFC 9643</dd> </dl> </section> </section> </middle> <back> <displayreference target="I-D.ietf-netconf-http-client-server" to="HTTP-CLIENT-SERVER"/> <displayreference target="I-D.ietf-netconf-netconf-client-server" to="NETCONF-CLIENT-SERVER"/> <displayreference target="I-D.ietf-netconf-restconf-client-server" to="RESTCONF-CLIENT-SERVER"/> <references> <name>References</name> <references> <name>Normative References</name><reference anchor="RFC2119" target="https://www.rfc-editor.org/info/rfc2119" xml:base="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.2119.xml"> <front> <title>Key words for use in RFCs to Indicate Requirement Levels</title> <author fullname="S. Bradner" initials="S." surname="Bradner"/> <date month="March" year="1997"/> <abstract> <t>In many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This<xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.2119.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.6020.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.6991.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.7950.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8174.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8341.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.9293.xml"/> <!-- [I-D.ietf-netconf-crypto-types] companion documentspecifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements.</t> </abstract> </front> <seriesInfo name="BCP" value="14"/> <seriesInfo name="RFC" value="2119"/> <seriesInfo name="DOI" value="10.17487/RFC2119"/> </reference>RFC 9640 --> <referenceanchor="RFC6020" target="https://www.rfc-editor.org/info/rfc6020" xml:base="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.6020.xml">anchor="RFC9640" target="https://www.rfc-editor.org/info/rfc9640"> <front> <title>YANG- ADataModeling LanguageTypes and Groupings forthe Network Configuration Protocol (NETCONF)</title>Cryptography</title> <authorfullname="M. Bjorklund" initials="M." role="editor" surname="Bjorklund"/>initials="K." surname="Watsen" fullname="Kent Watsen"> <organization>Watsen Networks</organization> </author> <datemonth="October" year="2010"/> <abstract> <t>YANG is a data modeling language used to model configuration and state data manipulated by the Network Configuration Protocol (NETCONF), NETCONF remote procedure calls, and NETCONF notifications. [STANDARDS-TRACK]</t> </abstract>month="August" year="2024"/> </front> <seriesInfo name="RFC"value="6020"/>value="9640"/> <seriesInfo name="DOI"value="10.17487/RFC6020"/>value="10.17487/RFC9640"/> </reference><reference anchor="RFC6991" target="https://www.rfc-editor.org/info/rfc6991" xml:base="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.6991.xml"> <front> <title>Common YANG Data Types</title> <author fullname="J. Schoenwaelder" initials="J." role="editor" surname="Schoenwaelder"/> <date month="July" year="2013"/> <abstract> <t>This document introduces a collection of common data types to be used with the YANG data modeling language. This</references> <references> <name>Informative References</name> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.1928.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.1929.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.2743.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.3688.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.6056.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.6241.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.6242.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8040.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8340.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8342.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8407.xml"/> <xi:include href="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8446.xml"/> <!-- [I-D.ietf-netconf-trust-anchors] companion documentobsoletesRFC6021.</t> </abstract> </front> <seriesInfo name="RFC" value="6991"/> <seriesInfo name="DOI" value="10.17487/RFC6991"/> </reference>9641 --> <referenceanchor="RFC7950" target="https://www.rfc-editor.org/info/rfc7950" xml:base="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.7950.xml">anchor="RFC9641" target="https://www.rfc-editor.org/info/rfc9641"> <front><title>The<title>A YANG1.1DataModeling Language</title> <author fullname="M. Bjorklund" initials="M." role="editor" surname="Bjorklund"/> <date month="August" year="2016"/> <abstract> <t>YANG is a data modeling language used to model configuration data, state data, Remote Procedure Calls, and notificationsModel fornetwork management protocols. This document describes the syntax and semantics of version 1.1 of the YANG language. YANG version 1.1 isamaintenance release of the YANG language, addressing ambiguities and defects in the original specification. There are a small number of backward incompatibilities from YANG version 1. This document also specifies the YANG mappings to the Network Configuration Protocol (NETCONF).</t> </abstract> </front> <seriesInfo name="RFC" value="7950"/> <seriesInfo name="DOI" value="10.17487/RFC7950"/> </reference> <reference anchor="RFC8174" target="https://www.rfc-editor.org/info/rfc8174" xml:base="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8174.xml"> <front> <title>Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words</title>Truststore</title> <authorfullname="B. Leiba" initials="B." surname="Leiba"/>initials="K." surname="Watsen" fullname="Kent Watsen"> <organization>Watsen Networks</organization> </author> <datemonth="May" year="2017"/> <abstract> <t>RFC 2119 specifies common key words that may be used in protocol specifications. This document aims to reduce the ambiguity by clarifying that only UPPERCASE usage of the key words have the defined special meanings.</t> </abstract>month="August" year="2024"/> </front> <seriesInfoname="BCP" value="14"/> <seriesInfoname="RFC"value="8174"/>value="9641"/> <seriesInfo name="DOI"value="10.17487/RFC8174"/>value="10.17487/RFC9641"/> </reference><reference anchor="RFC8341" target="https://www.rfc-editor.org/info/rfc8341" xml:base="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8341.xml"> <front> <title>Network Configuration Access Control Model</title> <author fullname="A. Bierman" initials="A." surname="Bierman"/> <author fullname="M. Bjorklund" initials="M." surname="Bjorklund"/> <date month="March" year="2018"/> <abstract> <t>The standardization of network configuration interfaces for use with the Network Configuration Protocol (NETCONF) or the RESTCONF protocol requires a structured and secure operating environment that promotes human usability and multi-vendor interoperability. There is a need for standard mechanisms to restrict NETCONF or RESTCONF protocol access for particular users to a preconfigured subset of all available NETCONF or RESTCONF protocol operations and content. This document defines such an access control model.</t> <t>This<!-- [I-D.ietf-netconf-keystore] companion documentobsoletesRFC6536.</t> </abstract> </front> <seriesInfo name="STD" value="91"/> <seriesInfo name="RFC" value="8341"/> <seriesInfo name="DOI" value="10.17487/RFC8341"/> </reference>9642 --> <referenceanchor="RFC9293" target="https://www.rfc-editor.org/info/rfc9293" xml:base="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.9293.xml">anchor="RFC9642" target="https://www.rfc-editor.org/info/rfc9642"> <front><title>Transmission Control Protocol (TCP)</title> <author fullname="W. Eddy" initials="W." role="editor" surname="Eddy"/> <date month="August" year="2022"/> <abstract> <t>This document specifies the Transmission Control Protocol (TCP). TCP is an important transport-layer protocol in the Internet protocol stack, and it has continuously evolved over decades of use and growth of the Internet. Over this time, a number of changes have been made to TCP as it was specified in RFC 793, though these have only been documented in a piecemeal fashion. This document collects and brings those changes together with the protocol specification from RFC 793. This document obsoletes RFC 793, as well as RFCs 879, 2873, 6093, 6429, 6528, and 6691 that updated parts of RFC 793. It updates RFCs 1011 and 1122, and it should be considered as a replacement<title>A YANG Data Model forthe portions of those documents dealing with TCP requirements. It also updates RFC 5961 by addingasmall clarification in reset handling while in the SYN-RECEIVED state. The TCP header control bits from RFC 793 have also been updated based on RFC 3168.</t> </abstract> </front> <seriesInfo name="STD" value="7"/> <seriesInfo name="RFC" value="9293"/> <seriesInfo name="DOI" value="10.17487/RFC9293"/> </reference> <xi:include href="https://datatracker.ietf.org/doc/bibxml3/reference.I-D.ietf-netconf-crypto-types.xml"/> </references> <references> <name>Informative References</name> <reference anchor="RFC1928" target="https://www.rfc-editor.org/info/rfc1928" xml:base="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.1928.xml"> <front> <title>SOCKS Protocol Version 5</title> <author fullname="M. Leech" initials="M." surname="Leech"/> <author fullname="M. Ganis" initials="M." surname="Ganis"/> <author fullname="Y. Lee" initials="Y." surname="Lee"/> <author fullname="R. Kuris" initials="R." surname="Kuris"/> <author fullname="D. Koblas" initials="D." surname="Koblas"/> <author fullname="L. Jones" initials="L." surname="Jones"/> <date month="March" year="1996"/> <abstract> <t>This memo describes a protocol that is an evolution of the previous version of the protocol, version 4 [1]. This new protocol stems from active discussionsKeystore andprototype implementations. [STANDARDS-TRACK]</t> </abstract> </front> <seriesInfo name="RFC" value="1928"/> <seriesInfo name="DOI" value="10.17487/RFC1928"/> </reference> <reference anchor="RFC1929" target="https://www.rfc-editor.org/info/rfc1929" xml:base="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.1929.xml"> <front> <title>Username/Password Authentication for SOCKS V5</title> <author fullname="M. Leech" initials="M." surname="Leech"/> <date month="March" year="1996"/> <abstract> <t>The protocol specification for SOCKS Version 5 specifies a generalized framework for the use of arbitrary authentication protocols in the initial socks connection setup. This document describes one of those protocols, as it fits into the SOCKS Version 5 authentication "subnegotiation". [STANDARDS-TRACK]</t> </abstract> </front> <seriesInfo name="RFC" value="1929"/> <seriesInfo name="DOI" value="10.17487/RFC1929"/> </reference> <reference anchor="RFC2743" target="https://www.rfc-editor.org/info/rfc2743" xml:base="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.2743.xml"> <front> <title>Generic Security Service Application Program Interface Version 2, Update 1</title>Keystore Operations</title> <authorfullname="J. Linn" initials="J." surname="Linn"/>initials="K." surname="Watsen" fullname="Kent Watsen"> <organization>Watsen Networks</organization> </author> <datemonth="January" year="2000"/> <abstract> <t>This memo obsoletes [STANDARDS-TRACK]</t> </abstract>month="August" year="2024"/> </front> <seriesInfo name="RFC"value="2743"/>value="9642"/> <seriesInfo name="DOI"value="10.17487/RFC2743"/>value="10.17487/RFC9642"/> </reference><reference anchor="RFC3688" target="https://www.rfc-editor.org/info/rfc3688" xml:base="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.3688.xml"> <front> <title>The IETF XML Registry</title> <author fullname="M. Mealling" initials="M." surname="Mealling"/> <date month="January" year="2004"/> <abstract> <t>This<!-- [I-D.ietf-netconf-ssh-client-server] companion documentdescribes an IANA maintained registry for IETF standards which use Extensible Markup Language (XML) related items such as Namespaces, Document Type Declarations (DTDs), Schemas, and Resource Description Framework (RDF) Schemas.</t> </abstract> </front> <seriesInfo name="BCP" value="81"/> <seriesInfo name="RFC" value="3688"/> <seriesInfo name="DOI" value="10.17487/RFC3688"/> </reference>RFC 9644 --> <referenceanchor="RFC6056" target="https://www.rfc-editor.org/info/rfc6056" xml:base="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.6056.xml">anchor="RFC9644" target="https://www.rfc-editor.org/info/rfc9644"> <front><title>Recommendations for Transport-Protocol Port Randomization</title> <author fullname="M. Larsen" initials="M." surname="Larsen"/> <author fullname="F. Gont" initials="F." surname="Gont"/> <date month="January" year="2011"/> <abstract> <t>During the last few years, awareness has been raised about a number of "blind" attacks that can be performed against the Transmission Control Protocol (TCP) and similar protocols. The consequences of these attacks range from throughput reduction to broken connections or data corruption. These attacks rely on the attacker's ability to guess or know the five-tuple (Protocol, Source Address, Destination Address, Source Port, Destination Port) that identifies the transport protocol instance to be attacked. This document describes a number of simple and efficient methods for the selection of the client port number, such that the possibility of an attacker guessing the exact value is reduced. While this is not a replacement for cryptographic methods<title>YANG Groupings forprotecting the transport-protocol instance, the aforementioned port selection algorithms provide improved security with very little effort and without any key management overhead. The algorithms described in this document are local policies that may be incrementally deployed and that do not violate the specifications of any of the transport protocols that may benefit from them, such as TCP, UDP, UDP-lite, Stream Control Transmission Protocol (SCTP), Datagram Congestion Control Protocol (DCCP), and RTP (provided that the RTP application explicitly signals the RTP and RTCP port numbers). This memo documents an Internet Best Current Practice.</t> </abstract> </front> <seriesInfo name="BCP" value="156"/> <seriesInfo name="RFC" value="6056"/> <seriesInfo name="DOI" value="10.17487/RFC6056"/> </reference> <reference anchor="RFC6241" target="https://www.rfc-editor.org/info/rfc6241" xml:base="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.6241.xml"> <front> <title>Network Configuration Protocol (NETCONF)</title> <author fullname="R. Enns" initials="R." role="editor" surname="Enns"/> <author fullname="M. Bjorklund" initials="M." role="editor" surname="Bjorklund"/> <author fullname="J. Schoenwaelder" initials="J." role="editor" surname="Schoenwaelder"/> <author fullname="A. Bierman" initials="A." role="editor" surname="Bierman"/> <date month="June" year="2011"/> <abstract> <t>The Network Configuration Protocol (NETCONF) defined in this document provides mechanisms to install, manipulate,SSH Clients anddelete the configuration of network devices. It uses an Extensible Markup Language (XML)-based data encoding for the configuration data as well as the protocol messages. The NETCONF protocol operations are realized as remote procedure calls (RPCs). This document obsoletes RFC 4741. [STANDARDS-TRACK]</t> </abstract> </front> <seriesInfo name="RFC" value="6241"/> <seriesInfo name="DOI" value="10.17487/RFC6241"/> </reference> <reference anchor="RFC8040" target="https://www.rfc-editor.org/info/rfc8040" xml:base="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8040.xml"> <front> <title>RESTCONF Protocol</title> <author fullname="A. Bierman" initials="A." surname="Bierman"/> <author fullname="M. Bjorklund" initials="M." surname="Bjorklund"/>SSH Servers</title> <authorfullname="K. Watsen"initials="K."surname="Watsen"/> <date month="January" year="2017"/> <abstract> <t>This document describes an HTTP-based protocol that provides a programmatic interface for accessing data defined in YANG, using the datastore concepts defined in the Network Configuration Protocol (NETCONF).</t> </abstract> </front> <seriesInfo name="RFC" value="8040"/> <seriesInfo name="DOI" value="10.17487/RFC8040"/> </reference> <reference anchor="RFC8340" target="https://www.rfc-editor.org/info/rfc8340" xml:base="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8340.xml"> <front> <title>YANG Tree Diagrams</title> <author fullname="M. Bjorklund" initials="M." surname="Bjorklund"/> <author fullname="L. Berger" initials="L." role="editor" surname="Berger"/>surname="Watsen" fullname="Kent Watsen"> <organization>Watsen Networks</organization> </author> <datemonth="March" year="2018"/> <abstract> <t>This document captures the current syntax used in YANG module tree diagrams. The purpose of this document is to provide a single location for this definition. This syntax may be updated from time to time based on the evolution of the YANG language.</t> </abstract>month="August" year="2024"/> </front> <seriesInfoname="BCP" value="215"/> <seriesInfoname="RFC"value="8340"/>value="9644"/> <seriesInfo name="DOI"value="10.17487/RFC8340"/>value="10.17487/RFC9644"/> </reference><reference anchor="RFC8342" target="https://www.rfc-editor.org/info/rfc8342" xml:base="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8342.xml"> <front> <title>Network Management Datastore Architecture (NMDA)</title> <author fullname="M. Bjorklund" initials="M." surname="Bjorklund"/> <author fullname="J. Schoenwaelder" initials="J." surname="Schoenwaelder"/> <author fullname="P. Shafer" initials="P." surname="Shafer"/> <author fullname="K. Watsen" initials="K." surname="Watsen"/> <author fullname="R. Wilton" initials="R." surname="Wilton"/> <date month="March" year="2018"/> <abstract> <t>Datastores are a fundamental concept binding the data models written in the YANG data modeling language to network management protocols such as the Network Configuration Protocol (NETCONF) and RESTCONF. This document defines an architectural framework for datastores based on the experience gained with the initial simpler model, addressing requirements that were not well supported in the initial model. This<!-- [I-D.ietf-netconf-tls-client-server] companion documentupdatesRFC7950.</t> </abstract> </front> <seriesInfo name="RFC" value="8342"/> <seriesInfo name="DOI" value="10.17487/RFC8342"/> </reference>9645 --> <referenceanchor="RFC8407" target="https://www.rfc-editor.org/info/rfc8407" xml:base="https://bib.ietf.org/public/rfc/bibxml/reference.RFC.8407.xml">anchor="RFC9645" target="https://www.rfc-editor.org/info/rfc9645"> <front><title>Guidelines<title>YANG Groupings forAuthorsTLS Clients andReviewers of Documents Containing YANG Data Models</title>TLS Servers</title> <authorfullname="A. Bierman" initials="A." surname="Bierman"/>initials="K." surname="Watsen" fullname="Kent Watsen"> <organization>Watsen Networks</organization> </author> <datemonth="October" year="2018"/> <abstract> <t>This memo provides guidelines for authors and reviewers of specifications containing YANG modules. Recommendations and procedures are defined, which are intended to increase interoperability and usability of Network Configuration Protocol (NETCONF) and RESTCONF protocol implementations that utilize YANG modules. This document obsoletes RFC 6087.</t> </abstract>month="August" year="2024"/> </front> <seriesInfoname="BCP" value="216"/> <seriesInfoname="RFC"value="8407"/>value="9645"/> <seriesInfo name="DOI"value="10.17487/RFC8407"/>value="10.17487/RFC9645"/> </reference> <!-- [I-D.ietf-netconf-http-client-server] IESG state: IESG Evaluation::AD Followup --> <xi:includehref="https://datatracker.ietf.org/doc/bibxml3/reference.I-D.ietf-netconf-trust-anchors.xml"/> <xi:include href="https://datatracker.ietf.org/doc/bibxml3/reference.I-D.ietf-netconf-keystore.xml"/> <xi:include href="https://datatracker.ietf.org/doc/bibxml3/reference.I-D.ietf-netconf-tcp-client-server.xml"/> <xi:include href="https://datatracker.ietf.org/doc/bibxml3/reference.I-D.ietf-netconf-ssh-client-server.xml"/> <xi:include href="https://datatracker.ietf.org/doc/bibxml3/reference.I-D.ietf-netconf-tls-client-server.xml"/> <xi:include href="https://datatracker.ietf.org/doc/bibxml3/reference.I-D.ietf-netconf-http-client-server.xml"/>href="https://bib.ietf.org/public/rfc/bibxml3/reference.I-D.ietf-netconf-http-client-server"/> <!-- [I-D.ietf-netconf-netconf-client-server] IESG state: AD Evaluation --> <xi:includehref="https://datatracker.ietf.org/doc/bibxml3/reference.I-D.ietf-netconf-netconf-client-server.xml"/>href="https://bib.ietf.org/public/rfc/bibxml3/reference.I-D.ietf-netconf-netconf-client-server"/> <!-- [I-D.ietf-netconf-restconf-client-server] IESG state: AD Evaluation--> <xi:includehref="https://datatracker.ietf.org/doc/bibxml3/reference.I-D.ietf-netconf-restconf-client-server.xml"/>href="https://bib.ietf.org/public/rfc/bibxml3/reference.I-D.ietf-netconf-restconf-client-server"/> <reference anchor="SOCKS_4A" target="https://www.openssh.com/txt/socks4a.protocol"> <front> <title>SOCKS 4A: A Simple Extension to SOCKS 4 Protocol</title> <authorfullname="The OpenSSH Project"/>fullname="Ying-Da Lee" surname="Lee" initials="Y."/> </front> </reference> </references> </references> <sectionanchor="change-log"> <name>Change Log</name> <section> <name>00 to 01</name> <ul spacing="normal"> <li>Added 'local-binding-supported' feature to TCP-client model.</li> <li>Added 'keepalives-supported' feature to TCP-common model.</li> <li>Added 'external-endpoint-values' container and 'external-endpoints' feature to TCP-server model.</li> </ul> </section> <section> <name>01 to 02</name> <ul spacing="normal"> <li>Removed the 'external-endpoint-values' container and 'external-endpoints' feature from the TCP-server model.</li> </ul> </section> <section> <name>02 to 03</name> <ul spacing="normal"> <li>Moved the common model section to be before the client and server specific sections.</li> <li>Added sections "Model Scope" and "Usage Guidelines for Configuring TCP Keep-Alives" to the common model section.</li> </ul> </section> <section> <name>03 to 04</name> <ul spacing="normal"> <li>Fixed a few typos.</li> </ul> </section> <section> <name>04 to 05</name> <ul spacing="normal"> <li>Removed commented out "grouping tcp-system-grouping" statement kept for reviewers.</li> <li>Added a "Note to Reviewers" note to first page.</li> </ul> </section> <section> <name>05 to 06</name> <ul spacing="normal"> <li>Added support for TCP proxies.</li> </ul> </section> <section> <name>06 to 07</name> <ul spacing="normal"> <li>Expanded "Data Model Overview section(s) [remove "wall" of tree diagrams].</li> <li>Updated the Security Considerations section.</li> </ul> </section> <section> <name>07 to 08</name> <ul spacing="normal"> <li>Added missing IANA registration for "ietf-tcp-common"</li> <li>Added "mandatory true" for the "username" and "password" leafs</li> <li>Added an example of a TCP-client configured to connect via a proxy</li> <li>Fixed issues found by the SecDir review of the "keystore" draft.</li> <li>Updated the "ietf-tcp-client" module to use the new "password-grouping" grouping from the "crypto-types" module.</li> </ul> </section> <section> <name>08 to 09</name> <ul spacing="normal"> <li>Addressed comments raised by YANG Doctor in the ct/ts/ks drafts.</li> </ul> </section> <section> <name>09 to 10</name> <ul spacing="normal"> <li>Updated Abstract and Intro to address comments by Tom Petch.</li> <li>Removed the "tcp-connection-grouping" grouping (now models use the "tcp-common-grouping" directly).</li> <li>Added XML-comment above examples explaining the reason for the unusual top-most element's presence.</li> <li>Added Securty Considerations section for the "local-binding-supported" feature.</li> <li>Replaced some hardcoded refs to <xref> elements.</li> <li>Fixed nits found by YANG Doctor reviews.</li> <li>Aligned modules with `pyang -f` formatting.</li> <li>Added an "Acknowledgements" secetion.</li> </ul> </section> <section> <name>10 to 11</name> <ul spacing="normal"> <li>Replaced "base64encodedvalue==" with "BASE64VALUE=" in examples.</li> <li>Minor editorial nits</li> </ul> </section> <section> <name>11 to 12</name> <ul spacing="normal"> <li>Fixed up the 'WG Web' and 'WG List' lines in YANG module(s)</li> <li>Fixed up copyright (i.e., s/Simplified/Revised/) in YANG module(s)</li> </ul> </section> <section> <name>12 to 13</name> <ul spacing="normal"> <li>NO UPDATE.</li> </ul> </section> <section> <name>13 to 14</name> <ul spacing="normal"> <li>Updated per Shepherd reviews impacting the suite of drafts.</li> </ul> </section> <section> <name>14 to 15</name> <ul spacing="normal"> <li>Updated per Shepherd reviews impacting the suite of drafts.</li> </ul> </section> <section> <name>15 to 16</name> <ul spacing="normal"> <li>Updated per Tom Petch review.</li> <li>Added refs to RFC9293 and SOCKS 4A.</li> <li>Fixed examples to use IETF-sanctioned values for examples.</li> </ul> </section> <section> <name>16 to 17</name> <ul spacing="normal"> <li>Addresses AD review comments.</li> <li>Added note to Editor to fix line foldings.</li> <li>Added Security Considerations text to also look a SC-section from imported modules.</li> <li>Fixed bug: s/augment "keepalives"/refine "keepalives"/</li> <li>Set defaults for idle-time, max-probes, and probe-interval (removed "mandatory true").</li> <li>Updated examples to use IETF recommended values for examples.</li> </ul> </section> <section> <name>18 to 19</name> <ul spacing="normal"> <li>Addresses AD review by Rob Wilton.</li> </ul> </section> <section> <name>18 to 19</name> <ul spacing="normal"> <li>Replace RFC 1122 with RFC 9293.</li> </ul> </section> <section> <name>19 to 20</name> <ul spacing="normal"> <li>Addresses 1st-round of IESG reviews.</li> </ul> </section> <section> <name>20 to 22</name> <ul spacing="normal"> <li>Addresses issues found in OpsDir review of the ssh-client-server draft.</li> <li>Updated to address Mallory Knodel's Gen-ART review.</li> <li>Renamed Security Considerations section s/Template for/Considerations for/</li> <li>s/defines/presents/ in a few places.</li> <li>Add refs to where the 'operational' and 'system' datastores are defined.</li> <li>Added more 'feature' statements and descriptions for them</li> <li>Added Security Considaration for the "password" node</li> </ul> </section> <section> <name>22 to 23</name> <ul spacing="normal"> <li>Address IESG review comments.</li> </ul> </section> <section> <name>23 to 24</name> <ul spacing="normal"> <li>Nothing changed. Bumped only for automation.</li> </ul> </section> <section> <name>24 to 25</name> <ul spacing="normal"> <li>Updated to support dual-stacks</li> </ul> </section> <section> <name>25 to 26</name> <ul spacing="normal"> <li>Updated to ensure at least one local-bind is specified.</li> </ul> </section> </section> <sectionnumbered="false"> <name>Acknowledgements</name> <t>The authors would like to thank the following for lively discussions on list and in the halls (ordered by first name):Éric Vyncke, Joe Clarke, Jürgen Schönwälder, Ladislav Lhotka, Mallory Knodel, Martin Duke, Michael Tüxen, Mohamed Boucadair, Nancy Cam-Winget, Nick Hancock, Per Andersson, Rob Wilton, Roman Danyliw, Tom Petch, Wim Henderickx.<contact fullname="Éric Vyncke"/>, <contact fullname="Joe Clarke"/>, <contact fullname="Jürgen Schönwälder"/>, <contact fullname="Ladislav Lhotka"/>, <contact fullname="Mallory Knodel"/>, <contact fullname="Martin Duke"/>, <contact fullname="Michael Tüxen"/>, <contact fullname="Mohamed Boucadair"/>, <contact fullname="Nancy Cam-Winget"/>, <contact fullname="Nick Hancock"/>, <contact fullname="Per Andersson"/>, <contact fullname="Rob Wilton"/>, <contact fullname="Roman Danyliw"/>, <contact fullname="Tom Petch"/>, and <contact fullname="Wim Henderickx"/>. </t> </section> <!-- [rfced] FYI - We have added expansions for the following abbreviations per Section 3.6 of RFC 7322 ("RFC Style Guide"). Please review each expansion in the document carefully to ensure correctness. Generic Security Service Application Program Interface (GSS-API) Network Configuration Protocol (NETCONF) Secure Shell (SSH) --> <!-- [rfced] Please review the "Inclusive Language" portion of the online Style Guide <https://www.rfc-editor.org/styleguide/part2/#inclusive_language> and let us know if any changes are needed. Note that our script did not flag any words in particular, but this should still be reviewed as a best practice. --> </back> </rfc>