Movatterモバイル変換


[0]ホーム

URL:


[RFC Home] [TEXT|PDF|HTML] [Tracker] [IPR] [Errata] [Info page]

HISTORIC
Updated by:8996Errata Exist
Network Working Group                                         T. GoddardRequest for Comments: 4743                     ICEsoft Technologies Inc.Category: Standards Track                                  December 2006Using NETCONF over the Simple Object Access Protocol (SOAP)Status of This Memo   This document specifies an Internet standards track protocol for the   Internet community, and requests discussion and suggestions for   improvements.  Please refer to the current edition of the "Internet   Official Protocol Standards" (STD 1) for the standardization state   and status of this protocol.  Distribution of this memo is unlimited.Copyright Notice   Copyright (C) The IETF Trust (2006).Abstract   The Network Configuration Protocol (NETCONF) is applicable to a wide   range of devices in a variety of environments.  Web Services is one   such environment and is presently characterized by the use of the   Simple Object Access Protocol (SOAP).  NETCONF finds many benefits in   this environment: from the reuse of existing standards, to ease of   software development, to integration with deployed systems.  Herein,   we describe SOAP over HTTP and SOAP over Blocks Exchange Extensible   Protocol (BEEP) bindings for NETCONF.Goddard                     Standards Track                     [Page 1]

RFC 4743                   NETCONF over SOAP               December 2006Table of Contents1. Introduction ....................................................22. SOAP Background for NETCONF .....................................32.1. Use and Storage of WSDL and XSD ............................42.2. SOAP over HTTP .............................................42.3. HTTP Drawbacks .............................................42.4.BCP56: On the Use of HTTP as a Substrate ...................52.5. Important HTTP 1.1 Features ................................62.6. SOAP over BEEP .............................................72.7. SOAP Implementation Considerations .........................72.7.1. SOAP Feature Exploitation ...........................72.7.2. SOAP Headers ........................................72.7.3. SOAP Faults .........................................83. A SOAP Service for NETCONF ......................................93.1. Fundamental Use Case .......................................93.2. NETCONF Session Establishment ..............................93.3. NETCONF Capabilities Exchange ..............................93.4. NETCONF Session Usage .....................................113.5. NETCONF Session Teardown ..................................113.6. A NETCONF over SOAP Example ...............................113.7. NETCONF SOAP WSDL .........................................133.8. Sample Service Definition WSDL ............................144. Security Considerations ........................................154.1. Integrity, Privacy, and Authentication ....................154.2. Vulnerabilities ...........................................164.3. Environmental Specifics ...................................165. IANA Considerations ............................................176. References .....................................................176.1. Normative References ......................................176.2. Informative References ....................................181.  Introduction   Given the use of Extensible Markup Language (XML) [2] and the remote   procedure call characteristics, it is natural to consider a binding   of the NETCONF [1] operations to a SOAP [3] application protocol.   This document proposes a binding of this form.   In general, SOAP is a natural messaging scheme for NETCONF,   essentially because of the remote procedure call character of both.   However, care must be taken with SOAP over HTTP as it is inherently   synchronous and client-driven.  SOAP over BEEP [11] is technically   superior, but is not as widely adopted.   Four basic topics are presented: SOAP specifics of interest to   NETCONF, specifics on implementing NETCONF as a SOAP-based web   service, security considerations, and functional Web ServicesGoddard                     Standards Track                     [Page 2]

RFC 4743                   NETCONF over SOAP               December 2006   Description Language (WSDL) definitions.  In some sense, the most   important part of the document is the brief WSDL document presented   inSection 3.7.  With the right tools, the WSDL combined with the   base NETCONF XML Schemas provides machine-readable descriptions   sufficient for the development of software applications using   NETCONF.   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this   document are to be interpreted as described inRFC 2119 [8].2.  SOAP Background for NETCONF   Why introduce SOAP as yet another wrapper around what is already a   remote procedure call message?  There are, in fact, both technical   and practical reasons.  The technical reasons are perhaps less   compelling, but let's examine them first.   The use of SOAP does offer a few technical advantages.  SOAP is   fundamentally an XML messaging scheme (which is capable of supporting   remote procedure call), and it defines a simple message format   composed of a "header" and a "body" contained within an "envelope".   The "header" contains meta-information relating to the message and   can be used to indicate such things as store-and-forward behaviour or   transactional characteristics.  In addition, SOAP specifies an   optional encoding for the "body" of the message.  However, this   encoding is not applicable to NETCONF as one of the goals is to have   highly readable XML, and SOAP-encoding is optimized instead for ease   of automated de-serialization.  These benefits of the SOAP message   structure are simple, but worthwhile because they are already   standardized.   It is the practical reasons that truly make SOAP an interesting   choice for device management.  It is not difficult to invent a   mechanism for exchanging XML messages over TCP, but what is difficult   is getting that mechanism supported in a wide variety of tools and   operating systems and having that mechanism understood by a great   many developers.  SOAP over HTTP (with WSDL) is seeing good success   at this, and this means that a device management protocol making use   of these technologies has advantages in being implemented and   adopted.  Admittedly, there are interoperability problems with SOAP   and WSDL, but such problems have wide attention and can be expected   to be resolved.Goddard                     Standards Track                     [Page 3]

RFC 4743                   NETCONF over SOAP               December 20062.1.  Use and Storage of WSDL and XSD   One of the advantages of using machine-readable formats (such as Web   Services Description Language (WSDL) [16] and XML Schemas [4]) is   that they can be used automatically in the software development   process.  With appropriate tools, WSDL and XSD can be used to   generate classes that act as remote interfaces or   application-specific data structures.  Other uses, such as document   generation and service location, are also common.  A great innovation   found with many XML-based definition languages is the use of   hyperlinks for referring to documents containing supporting   definitions.     <import namespace="urn:ietf:params:xml:ns:netconf:base:1.0"             location="http://www.iana.org/assignments/xml-registry/                       schema/netconf.xsd" />   For instance, in WSDL, the above import statement imports the   definitions of XML types and elements from the base NETCONF schema.   Ideally, the file containing that schema is hosted on a web server   under the authority of the standards body that defined the schema.   In this way, dependent standards can be built up over time, and all   are accessible to automated software tools that ensure adherence to   the standards.  The IANA-maintained registry for this purpose is   described in "The IETF XML Registry" [13].   Note that WSDL declarations for SOAP over BEEP bindings are not yet   standardized.2.2.  SOAP over HTTP   Although SOAP focuses on messages and can be bound to different   underlying protocols such as HTTP, SMTP, or BEEP, most existing SOAP   implementations support only HTTP or HTTP/TLS.   There are a number of advantages to considering SOAP over protocols   other than HTTP, as HTTP assigns the very distinct client and server   roles by connection initiation.  This causes difficulties in   supporting asynchronous notification and can be relieved in many ways   by replacing HTTP with BEEP.2.3.  HTTP Drawbacks   HTTP is not the ideal transport for messaging, but it is adequate for   the most basic interpretation of "remote procedure call".  HTTP is   based on a communication pattern whereby the client (which initiates   the TCP connection) makes a "request" to the server.  The server   returns a "response", and this process is continued (possibly over aGoddard                     Standards Track                     [Page 4]

RFC 4743                   NETCONF over SOAP               December 2006   persistent connection, as described below).  This matches the basic   idea of a remote procedure call where the caller invokes a procedure   on a remote server and waits for the return value.   Potential criticisms of HTTP could include the following:   o  Server-initiated data flow is awkward to provide.   o  Headers are verbose and text-based   o  Idle connections may be closed by intermediate proxies   o  Data encapsulation must adhere to Multipurpose Internet Mail      Extensions (MIME) [15].   o  Bulk transfer relies on stream-based ordering.   In many ways, these criticisms are directed at particular compromises   in the design of HTTP.  As such, they are important to consider, but   it is not clear that they result in fatal drawbacks for a device   management protocol.2.4.BCP56: On the Use of HTTP as a Substrate   Best Current Practice 56 [6] presents a number of important   considerations on the use of HTTP in application protocols.  In   particular, it raises the following concerns:   o  HTTP may be more complex than is necessary for the application.   o  The use of HTTP may mask the application from some firewalls.   o  A substantially new service should not reuse port 80 as assigned      to HTTP.   o  HTTP caching may mask connection state.   Fundamentally, these concerns lie directly with common usage of SOAP   over HTTP, rather than the application of SOAP over HTTP to NETCONF.   AsBCP 56 indicates, it is debatable whether HTTP is an appropriate   protocol for SOAP at all, and it is likely that BEEP would be a   superior protocol for most SOAP applications.  Unfortunately, SOAP   over HTTP is in common use and must be supported if the practical   benefits of SOAP are to be realized.  Note that the verbose nature of   SOAP actually makes it more readily processed by firewalls, albeit   firewalls designed to process SOAP messages.Goddard                     Standards Track                     [Page 5]

RFC 4743                   NETCONF over SOAP               December 2006   HTTP caches SHOULD NOT be inserted between NETCONF managers and   agents as NETCONF session state is tied to the state of the   underlying transport connection.  Three defensive actions can be   taken:   o  Caching MUST be prohibited through the use of HTTP headers Cache-      Control and Pragma: no-cache.   o  HTTP proxies SHOULD NOT be deployed within the management network.   o  Use HTTPS.   It is also possible to respond to the concern on the reuse of port   80.  Any NETCONF SOAP service MUST always be supported over the new   standard port for NETCONF over SOAP, and all conforming   implementations MUST default to attempting connections over this new   standard port for NETCONF.  A standard port for NETCONF over SOAP   (over HTTP) has been assigned in the IANA considerations of this   document.2.5.  Important HTTP 1.1 Features   HTTP 1.1 [5] includes two important features that provide for   relatively efficient transport of SOAP messages.  These features are   "persistent connections" and "chunked transfer-coding".   Persistent connections allow a single TCP connection to be used   across multiple HTTP requests.  This permits multiple SOAP request/   response message pairs to be exchanged without the overhead of   creating a new TCP connection for each request.  Given that a single   stream is used for both requests and responses, it is clear that some   form of framing is necessary.  For messages whose length is known in   advance, this is handled by the HTTP header "Content-length".  For   messages of dynamic length, "Chunking" is required.   HTTP "Chunking" or "chunked transfer-coding" allows the sender to   send an indefinite amount of binary data.  This is accomplished by   informing the receiver of the size of each "chunk" (substring of the   data) before the chunk is transmitted.  The last chunk is indicated   by a chunk of zero length.  Chunking can be effectively used to   transfer a large XML document where the document is generated on-line   from a non-XML form in memory.   In terms of its application to SOAP message exchanges, persistent   connections are clearly important for performance reasons and are   particularly important when the persistence of authenticated   connections is at stake.  When one considers that messages of dynamic   length are the rule rather than the exception for SOAP messages, itGoddard                     Standards Track                     [Page 6]

RFC 4743                   NETCONF over SOAP               December 2006   is also clear that Chunking is very useful.  In some cases, it is   possible to buffer a SOAP response and determine its length before   sending, but the storage requirements for this are prohibitive for   many devices.  Together, these two features provide a good foundation   for device management using SOAP over HTTP.  HTTP chunking and   persistent connections [5] SHOULD be used.2.6.  SOAP over BEEP   Although not widely adopted by the Web Services community, BEEP is an   excellent substrate for SOAP [12].  In particular, it provides for   request/response message exchanges initiated by either BEEP peer and   allows the number of response messages to be arbitrary (including   zero).  The BEEP profile for SOAP simply makes use of a single BEEP   channel for exchanging SOAP messages and benefits from BEEP's   inherent strengths for message exchange over a single transport   connection.2.7.  SOAP Implementation Considerations   It is not the goal of this document to cover the SOAP [3]   specification in detail.  Instead, we provide a few comments that may   be of interest to an implementor of NETCONF over SOAP.2.7.1.  SOAP Feature Exploitation   NETCONF over SOAP does not make extensive use of SOAP features.  For   instance, NETCONF operations are not broken into SOAP message parts,   and the SOAP header is not used to convey <rpc> metadata.  This is a   deliberate design decision as it allows the implementor to provide   NETCONF over multiple substrates easily while handling the messages   over those different substrates in a common way.2.7.2.  SOAP Headers   Implementers of NETCONF over SOAP should be aware of the following   characteristic of SOAP headers: a SOAP header may have the attribute   "mustUnderstand", and, if it does, the recipient must either process   the header block or not process the SOAP message at all, and instead   generate a fault.  A "mustUnderstand" header must not be silently   discarded.   In general, however, SOAP headers are intended for application-   specific uses.  The NETCONF SOAP binding does not make use of SOAP   headers.Goddard                     Standards Track                     [Page 7]

RFC 4743                   NETCONF over SOAP               December 20062.7.3.  SOAP Faults   A SOAP Fault is returned in the event of a NETCONF <rpc-error>.  It   is constructed essentially as a wrapper for the <rpc-error>, but it   allows SOAP processors to propagate the <rpc-error> to application   code using a language-appropriate exception mechanism.   A SOAP Fault is constructed from an <rpc-error> as follows: the SOAP   Fault Code Value is "Receiver" in the SOAP envelope namespace, the   SOAP Fault Reason Text is the contents of the NETCONF <rpc-error>   "error-tag", and the SOAP Fault detail is the original <rpc-error>   structure.   For instance, given the following <rpc-error>,       <rpc-error xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">         <error-type>rpc</error-type>         <error-tag>MISSING_ATTRIBUTE</error-tag>         <error-severity>error</error-severity>         <error-info>           <bad-attribute>message-id</bad-attribute>           <bad-element>rpc</bad-element>         </error-info>       </rpc-error>   the associated SOAP Fault message is       <soapenv:Envelope           xmlns:soapenv=             "http://www.w3.org/2003/05/soap-envelope"           xmlns:xml="http://www.w3.org/XML/1998/namespace">         <soapenv:Body>           <soapenv:Fault>             <soapenv:Code>               <soapenv:Value>env:Receiver</soapenv:Value>             </soapenv:Code>             <soapenv:Reason>               <soapenv:Text                   xml:lang="en">MISSING_ATTRIBUTE</soapenv:Text>             </soapenv:Reason>             <detail>               <rpc-error xmlns=                   "urn:ietf:params:xml:ns:netconf:base:1.0">                 <error-type>rpc</error-type>                 <error-tag>MISSING_ATTRIBUTE</error-tag>                 <error-severity>error</error-severity>                 <error-info>                   <bad-attribute>message-id</bad-attribute>Goddard                     Standards Track                     [Page 8]

RFC 4743                   NETCONF over SOAP               December 2006                   <bad-element>rpc</bad-element>                 </error-info>               </rpc-error>             </detail>           </soapenv:Fault>         </soapenv:Body>       </soapenv:Envelope>3.  A SOAP Service for NETCONF3.1.  Fundamental Use Case   The fundamental use case for NETCONF over SOAP is that of a   management console ("manager" role) managing one or more devices   running NETCONF agents ("agent" role).  The manager initiates an HTTP   or BEEP connection to an agent and drives the NETCONF session via a   sequence of SOAP messages.  When the manager closes the connection,   the NETCONF session is also closed.3.2.  NETCONF Session Establishment   A NETCONF over SOAP session is established by the initial message   exchange on the underlying substrate.  For HTTP, a NETCONF session is   established once a SOAP message is POSTed to the NETCONF web   application URI.  For BEEP, a NETCONF session is established once the   BEEP profile for SOAP handshake establishes the SOAP channel.3.3.  NETCONF Capabilities Exchange   Capabilities exchange and session ID establishment are performed   through the exchange of <hello> messages.  In the case of SOAP over   HTTP, the HTTP client MUST send the first <hello> message.  The case   of SOAP over BEEP imposes no ordering constraints.  For instance, the   following example shows the exchange of <hello> messages and   establishes a session ID value of 4.  Observe that the management   client initiates the exchange and the server agent assigns the   session ID.Goddard                     Standards Track                     [Page 9]

RFC 4743                   NETCONF over SOAP               December 2006   C: POST /netconf HTTP/1.1   C: Host: netconfdevice   C: Content-Type: text/xml; charset=utf-8   C: Accept: application/soap+xml, text/*   C: Cache-Control: no-cache   C: Pragma: no-cache   C: Content-Length: 376   C:   C: <?xml version="1.0" encoding="UTF-8"?>   C: <soapenv:Envelope   C:   xmlns:soapenv="http://www.w3.org/2003/05/soap-envelope">   C:   <soapenv:Body>   C:     <hello xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">   C:       <capabilities>   C:         <capability>   C:           urn:ietf:params:netconf:base:1.0   C:         </capability>   C:       </capabilities>   C:     </hello>   C:   </soapenv:Body>   C: </soapenv:Envelope>   S: HTTP/1.1 200 OK   S: Content-Type: application/soap+xml; charset=utf-8   S: Content-Length: 600   S:   S: <?xml version="1.0" encoding="UTF-8"?>   S: <soapenv:Envelope   S:   xmlns:soapenv="http://www.w3.org/2003/05/soap-envelope">   S:   <soapenv:Body>   S:     <hello xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">   S:       <capabilities>   S:         <capability>   S:           urn:ietf:params:netconf:base:1.0   S:         </capability>   S:         <capability>   S:           urn:ietf:params:netconf:capability:startup:1.0   S:         </capability>   S:         <capability>   S:           http:/example.net/router/2.3/myfeature   S:        </capability>   S:       </capabilities>   S:       <session-id>4</session-id>   S:     </hello>   S:   </soapenv:Body>   S: </soapenv:Envelope>Goddard                     Standards Track                    [Page 10]

RFC 4743                   NETCONF over SOAP               December 20063.4.  NETCONF Session Usage   NETCONF sessions are persistent for both performance and semantic   reasons.  NETCONF session state contains the following:   1.  Authentication Information   2.  Capability Information   3.  Locks   4.  Pending Operations   5.  Operation Sequence Numbers   Authentication must be maintained throughout a session due to the   fact that it is expensive to establish.  Capability Information is   maintained so that appropriate operations can be applied during a   session.  Locks are released upon termination of a session as this   makes the protocol more robust.  Pending operations come and go from   existence during the normal course of remote procedure call (RPC)   operations.  Operation sequence numbers provide the small but   necessary state information to refer to operations during the   session.   In the case of SOAP over HTTP, a NETCONF session is supported by an   HTTP connection with an authenticated user.  For SOAP over BEEP, a   NETCONF session is supported by a BEEP channel operating according to   the BEEP profile for SOAP [12].3.5.  NETCONF Session Teardown   To allow automated cleanup, NETCONF over SOAP session teardown takes   place when the underlying connection (in the case of HTTP) or channel   (in the case of BEEP) is closed.  Note that the root cause of such   teardown may be the closure of the TCP connection under either HTTP   or BEEP as the case may be.  NETCONF managers and agents must be   capable of programatically closing the transport connections   associated with NETCONF sessions, such as in response to a   <close-session> operation; thus, the HTTP or BEEP substrate   implementation must expose this appropriately.3.6.  A NETCONF over SOAP Example   Since the proposed WSDL (inSection 3.7) uses document/literal   encoding, the use of a SOAP header and body has little impact on the   representation of a NETCONF operation.  This example shows HTTP/1.1   for simplicity.  An example for BEEP would be similar.Goddard                     Standards Track                    [Page 11]

RFC 4743                   NETCONF over SOAP               December 2006   C: POST /netconf HTTP/1.1   C: Host: netconfdevice   C: Content-Type: text/xml; charset=utf-8   C: Accept: application/soap+xml, text/*   C: Cache-Control: no-cache   C: Pragma: no-cache   C: Content-Length: 465   C:   C: <?xml version="1.0" encoding="UTF-8"?>   C: <soapenv:Envelope   C:   xmlns:soapenv="http://www.w3.org/2003/05/soap-envelope">   C:   <soapenv:Body>   C:     <rpc message-id="101"   C:          xmlns="xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">   C:       <get-config>   C:         <filter type="subtree">   C:           <top xmlns="http://example.com/schema/1.2/config">   C:             <users/>   C:           </top>   C:         </filter>   C:       </get-config>   C:     </rpc>   C:   </soapenv:Body>   C: </soapenv:Envelope>   The HTTP/1.1 response is also straightforward:   S: HTTP/1.1 200 OK   S: Content-Type: application/soap+xml; charset=utf-8   S: Content-Length: 917   S:   S: <?xml version="1.0" encoding="UTF-8"?>   S: <soapenv:Envelope   S:   xmlns:soapenv="http://www.w3.org/2003/05/soap-envelope">   S:   <soapenv:Body>   S:     <rpc-reply message-id="101"   S:                xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">   S:       <data>   S:         <top xmlns="http://example.com/schema/1.2/config">   S:           <users>   S:             <user>   S:               <name>root</name>   S:               <type>superuser</type>   S:               <full-name>Charlie Root</full-name>   S:                 <dept>1</dept>   S:                 <id>1</id>   S:               </company-info>   S:             </user>Goddard                     Standards Track                    [Page 12]

RFC 4743                   NETCONF over SOAP               December 2006   S:             <user>   S:               <name>fred</name>   S:               <type>admin</type>   S:               <full-name>Fred Flintstone</full-name>   S:                 <dept>2</dept>   S:                 <id>2</id>   S:               </company-info>   S:             </user>   S:           </users>   S:         </top>   S:       </data>   S:     </rpc-reply>   S:   </soapenv:Body>   S: </soapenv:Envelope>3.7.  NETCONF SOAP WSDL   <?xml version="1.0" encoding="UTF-8"?>   <definitions     xmlns="http://schemas.xmlsoap.org/wsdl/"     xmlns:SOAP="http://schemas.xmlsoap.org/wsdl/soap/"     xmlns:tns="urn:ietf:params:xml:ns:netconf:soap:1.0"     xmlns:netb="urn:ietf:params:xml:ns:netconf:base:1.0"     targetNamespace="urn:ietf:params:xml:ns:netconf:soap:1.0"     name="netconf-soap_1.0.wsdl">     <import namespace="urn:ietf:params:xml:ns:netconf:base:1.0"             location="http://www.iana.org/assignments/xml-registry/                       schema/netconf.xsd" />     <message name="helloRequest">       <part name="in" element="netb:hello"/>     </message>     <message name="helloResponse">       <part name="out" element="netb:hello"/>     </message>     <message name="rpcRequest">       <part name="in" element="netb:rpc"/>     </message>     <message name="rpcResponse">       <part name="out" element="netb:rpc-reply"/>     </message>     <portType name="netconfPortType">       <operation name="rpc">         <input message="tns:rpcRequest"/>         <output message="tns:rpcResponse"/>Goddard                     Standards Track                    [Page 13]

RFC 4743                   NETCONF over SOAP               December 2006       </operation>       <operation name="hello">         <input message="tns:helloRequest"/>         <output message="tns:helloResponse"/>       </operation>     </portType>     <binding name="netconfBinding" type="tns:netconfPortType">       <SOAP:binding            transport="http://schemas.xmlsoap.org/soap/http"/>       <operation name="hello">         <SOAP:operation/>         <input>           <SOAP:body use="literal"                namespace="urn:ietf:params:xml:ns:netconf:soap:1.0"/>         </input>         <output>           <SOAP:body use="literal"                namespace="urn:ietf:params:xml:ns:netconf:soap:1.0"/>         </output>       </operation>       <operation name="rpc">         <SOAP:operation/>         <input>           <SOAP:body use="literal"                namespace="urn:ietf:params:xml:ns:netconf:base:1.0"/>         </input>         <output>           <SOAP:body use="literal"                namespace="urn:ietf:params:xml:ns:netconf:base:1.0"/>         </output>       </operation>     </binding>   </definitions>3.8.  Sample Service Definition WSDL   The following WSDL document assumes a local location for the NETCONF   over SOAP WSDL definitions.  A typical deployment of a device   manageable via NETCONF over SOAP would provide a service definition   similar to the following to identify the address of the device.   <?xml version="1.0" encoding="UTF-8"?>   <definitions     xmlns="http://schemas.xmlsoap.org/wsdl/"     xmlns:SOAP="http://schemas.xmlsoap.org/wsdl/soap/"     xmlns:nets="urn:ietf:params:xml:ns:netconf:soap:1.0"Goddard                     Standards Track                    [Page 14]

RFC 4743                   NETCONF over SOAP               December 2006     targetNamespace="urn:myNetconfService"     name="myNetconfService.wsdl">     <import namespace="urn:ietf:params:xml:ns:netconf:soap:1.0"             location="http://localhost:8080/netconf/                       schema/netconf-soap_1.0.wsdl"/>     <service name="netconf">       <port name="netconfPort" binding="nets:netconfBinding">         <SOAP:address location="http://localhost:8080/netconf"/>       </port>     </service>   </definitions>4.  Security Considerations   NETCONF is used to access and modify configuration information, so   the ability to access this protocol should be limited to users and   systems that are authorized to view or modify the agent's   configuration data.   Because configuration information is sent in both directions, it is   not sufficient for just the client or user to be authenticated with   the server.  The identity of the server should also be authenticated   with the client.   Configuration data may include sensitive information, such as user   names or security keys.  So, NETCONF should only be used over   communications channels that provide strong encryption for data   privacy.   If the NETCONF server provides remote access through insecure   protocols, such as HTTP, care should be taken to prevent execution of   the NETCONF program when strong user authentication or data privacy   is not available.   The IANA assigned port SHOULD be used, as this provides a means for   efficient firewall filtering during possible denial-of-service   attacks.4.1.  Integrity, Privacy, and Authentication   The NETCONF SOAP binding relies on an underlying secure transport for   integrity and privacy.  Such transports are expected to include TLS   [9] (which, when combined with HTTP, is referred to as HTTPS) and   IPsec.  There are a number of options for authentication (some of   which are deployment-specific):Goddard                     Standards Track                    [Page 15]

RFC 4743                   NETCONF over SOAP               December 2006   o  within the transport (such as with TLS client certificates)   o  within HTTP (such as Digest Access Authentication [7])   o  within SOAP (such as a digital signature in the header [17])   HTTP, BEEP, and SOAP level authentication can be integrated with   Remote Authentication Dial-In User Service (RADIUS) [10] to support   remote authentication databases.   At a miniumum, all conforming NETCONF over SOAP implementations MUST   support TLS.  Specifically, NETCONF over SOAP over HTTP MUST support   NETCONF over SOAP over HTTPS, and NETCONF over SOAP over BEEP MUST   support NETCONF over SOAP over BEEP over TLS.4.2.  Vulnerabilities   The above protocols may have various vulnerabilities, and these may   be inherited by NETCONF over SOAP.   NETCONF itself may have vulnerabilities because an authorization   model is not currently specified.   It is important that device capabilities and authorization remain   constant for the duration of any outstanding NETCONF session.  In the   case of NETCONF, it is important to consider that device management   may be taking place over multiple substrates (in addition to SOAP),   and it is important that the different substrates have a common   authentication model.4.3.  Environmental Specifics   Some deployments of NETCONF over SOAP may choose to use transports   without encryption.  This presents vulnerabilities but may be   selected for deployments involving closed networks or debugging   scenarios.   A device managed by NETCONF may interact (over protocols besides   NETCONF) with devices managed by other protocols, all of differing   security.  Each point of entry brings with it a potential   vulnerability.Goddard                     Standards Track                    [Page 16]

RFC 4743                   NETCONF over SOAP               December 20065.  IANA Considerations   IANA assigned TCP port (833) for NETCONF over SOAP over BEEP, and TCP   port (832) for NETCONF over SOAP over HTTPS.   IANA will allow for the assignment of an XML namespace within the   NETCONF namespace "urn:ietf:params:xml:ns:netconf" for the NETCONF   over SOAP WSDL definitions.  Following the policies outlined inRFC2434 [14], assigned values in this subordinate namespace are   requested to be allocated according to the "Specification Required"   policy.   URI: urn:ietf:params:xml:ns:netconf:soap6.  References6.1.  Normative References   [1]   Enns, R., Ed., "NETCONF Configuration Protocol",RFC 4741,         December 2006.   [2]   Bray, T., Paoli, J., Sperberg-McQueen, C., and E. Maler,         "Extensible Markup Language (XML) 1.0 (Second Edition)", W3C         REC REC-xml-20001006, October 2000,         <http://www.w3.org/TR/2000/REC-xml-20001006>.   [3]   Gudgin, M., Hadley, M., Moreau, JJ., and H. Nielsen, "SOAP         Version 1.2 Part 1: Messaging Framework", W3C         Recommendation REC-soap12-part1-20030624, June 2002,         <http://www.w3.org/TR/soap12-part1/>.   [4]   Thompson, H., Beech, D., Maloney, M., and N. Mendelsohn, "XML         Schema Part 1: Structures", W3C Recommendation REC-xmlschema-         1-20010502, May 2001,         <http://www.w3.org/TR/2001/REC-xmlschema-1-20010502/>.   [5]   Fielding, R., Gettys, J., Mogul, J., Frystyk, H., Masinter, L.,         Leach, P., and T. Berners-Lee, "Hypertext Transfer Protocol --         HTTP/1.1",RFC 2616, June 1999.   [6]   Moore, K., "On the use of HTTP as a Substrate",RFC 3205,         February 2002.   [7]   Franks, J., Hallam-Baker, P., Hostetler, J., Leach, P.,         Luotonen, A., Sink, E., and L. Stewart, "HTTP Authentication:         Basic and Digest Access Authentication",RFC 2617, June 1999.Goddard                     Standards Track                    [Page 17]

RFC 4743                   NETCONF over SOAP               December 2006   [8]   Bradner, S., "Key words for use in RFCs to Indicate Requirement         Levels",RFC 2119, March 1997.   [9]   Dierks, T. and E. Rescorla, "The Transport Layer Security (TLS)         Protocol Version 1.1",RFC 4346, April 2006.   [10]  Rigney, C., Willens, S., Rubens, A., and W. Simpson, "Remote         Authentication Dial In User Service (RADIUS)",RFC 2865,         June 2000.   [11]  Rose, M., "The Blocks Extensible Exchange Protocol Core",RFC 3080, March 2001.   [12]  O'Tuathail, E. and M. Rose, "Using the Simple Object Access         Protocol (SOAP) in Blocks Extensible Exchange Protocol (BEEP)",RFC 4227, January 2006.   [13]  Mealling, M., "The IETF XML Registry",RFC 3688, January 2004.   [14]  Alvestrand, H. and T. Narten, "Guidelines for Writing an IANA         Considerations Section in RFCs",RFC 2434, October 1998.6.2.  Informative References   [15]  Freed, N. and N. Borenstein, "Multipurpose Internet Mail         Extensions (MIME) Part One: Format of Internet Message Bodies",RFC 2045, November 1996.   [16]  Christensen, E., Curbera, F., Meredith, G., and S. Weerawarana,         "Web Services Description Language (WSDL) 1.1", W3C Note NOTE-         wsdl-20010315, March 2001,         <http://www.w3.org/TR/2001/NOTE-wsdl-20010315>.   [17]  Brown, A., Fox, B., Hada, S., LaMacchia, B., and H. Maruyama,         "SOAP Security Extensions: Digital Signature", W3C Note NOTE-         SOAP-dsig-20010206, Feb 2001,         <http://www.w3.org/TR/SOAP-dsig/>.Goddard                     Standards Track                    [Page 18]

RFC 4743                   NETCONF over SOAP               December 2006Author's Address   Ted Goddard   ICEsoft Technologies Inc.   Suite 300, 1717 10th St. NW   Calgary, AB  T2M 4S2   Canada   Phone: (403) 663-3322   EMail: ted.goddard@icesoft.com   URI:http://www.icesoft.comGoddard                     Standards Track                    [Page 19]

RFC 4743                   NETCONF over SOAP               December 2006Full Copyright Statement   Copyright (C) The IETF Trust (2006).   This document is subject to the rights, licenses and restrictions   contained inBCP 78, and except as set forth therein, the authors   retain all their rights.   This document and the information contained herein are provided on an   "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS   OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST,   AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES,   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT   THE USE OF THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY   IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR   PURPOSE.Intellectual Property   The IETF takes no position regarding the validity or scope of any   Intellectual Property Rights or other rights that might be claimed to   pertain to the implementation or use of the technology described in   this document or the extent to which any license under such rights   might or might not be available; nor does it represent that it has   made any independent effort to identify any such rights.  Information   on the procedures with respect to rights in RFC documents can be   found inBCP 78 andBCP 79.   Copies of IPR disclosures made to the IETF Secretariat and any   assurances of licenses to be made available, or the result of an   attempt made to obtain a general license or permission for the use of   such proprietary rights by implementers or users of this   specification can be obtained from the IETF on-line IPR repository athttp://www.ietf.org/ipr.   The IETF invites any interested party to bring to its attention any   copyrights, patents or patent applications, or other proprietary   rights that may cover technology that may be required to implement   this standard.  Please address the information to the IETF at   ietf-ipr@ietf.org.Acknowledgement   Funding for the RFC Editor function is currently provided by the   Internet Society.Goddard                     Standards Track                    [Page 20]

[8]ページ先頭

©2009-2025 Movatter.jp