Network Working Group P. Faltstrom
Request for Comments: 2916 Cisco Systems Inc.
Category: Standards Track September 2000
Network Working Group P. Faltstrom
Request for Comments: 2916 Cisco Systems Inc.
Category: Standards Track September 2000
E.164 number and DNS
E.164编号和DNS
Status of this Memo
本备忘录的状况
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.
本文件规定了互联网社区的互联网标准跟踪协议，并要求进行讨论和提出改进建议。有关本协议的标准化状态和状态，请参考当前版本的“互联网官方协议标准”（STD 1）。本备忘录的分发不受限制。
Copyright Notice
版权公告
Copyright (C) The Internet Society (2000). All Rights Reserved.
版权所有（C）互联网协会（2000年）。版权所有。
Abstract
摘要
This document discusses the use of the Domain Name System (DNS) for storage of E.164 numbers. More specifically, how DNS can be used for identifying available services connected to one E.164 number. Routing of the actual connection using the service selected using these methods is not discussed.
本文档讨论使用域名系统（DNS）存储E.164号码。更具体地说，DNS如何用于识别连接到一个E.164号码的可用服务。不讨论使用使用这些方法选择的服务的实际连接的路由。
Through transformation of E.164 numbers into DNS names and the use of existing DNS services like delegation through NS records, and use of NAPTR [1] records in DNS [2] [3], one can look up what services are available for a specific domain name in a decentralized way with distributed management of the different levels in the lookup process.
通过将E.164号转换为DNS名称，并使用现有DNS服务，如通过NS记录进行授权，以及在DNS[2][3]中使用NAPTR[1]记录，可以通过分布式管理查找过程中的不同级别，以分散的方式查找特定域名的可用服务。
The key words "MUST", "REQUIRED", "SHOULD", "RECOMMENDED", and "MAY" in this document are to be interpreted as described in RFC2119 [4].
本文件中的关键词“必须”、“要求”、“应该”、“建议”和“可能”应按照RFC2119[4]中的描述进行解释。
The domain "e164.arpa" is being populated in order to provide the infrastructure in DNS for storage of E.164 numbers. In order to facilitate distributed operations, this domain is divided into subdomains. Holders of E.164 numbers which want to be listed in DNS
正在填充域“e164.arpa”，以便在DNS中提供存储E.164号码的基础设施。为了便于分布式操作，该域被划分为子域。希望在DNS中列出的E.164号码的持有者
should contact the appropriate zone administrator in order to be listed, by examining the SOA resource record associated with the zone, just like in normal DNS operations.
应该通过检查与区域关联的SOA资源记录来联系相应的区域管理员，以便被列出，就像在正常DNS操作中一样。
Of course, as with other domains, policies for such listings will be controlled on a subdomain basis and may differ in different parts of the world.
当然，与其他域一样，此类列表的策略将在子域基础上进行控制，并且可能在世界不同地区有所不同。
To find the DNS names for a specific E.164 number, the following procedure is to be followed:
要查找特定E.164号码的DNS名称，请遵循以下步骤：
1. See that the E.164 number is written in its full form, including the countrycode IDDD. Example: +46-8-9761234
1. 请确保E.164编号以完整形式书写，包括国家代码IDDD。示例：+46-8-9761234
2. Remove all non-digit characters with the exception of the leading '+'. Example: +4689761234
2. 删除所有非数字字符，前导“+”除外。示例：+4689761234
3. Remove all characters with the exception of the digits. Example: 4689761234
3. 删除除数字以外的所有字符。示例：4689761234
6. Append the string ".e164.arpa" to the end. Example: 4.3.2.1.6.7.9.8.6.4.e164.arpa
6. 在末尾追加字符串“.e164.arpa”。示例：4.3.2.1.6.7.9.8.6.4.e164.arpa
The '+' is kept in stage 2 in section 2 to flag that the number which the regular expression is operating on is a E.164 number. Future work will be needed to determine how other numbering plans (such as closed ones) might be identified. It is possible, but not definite, that they would use a similar mechanism as the one described in this document.
在第2节的第2阶段中保留“+”以标记正则表达式所操作的数字是E.164数字。需要进一步确定如何确定其他编号计划（如已关闭的计划）。他们可能（但不确定）使用与本文件所述类似的机制。
For a record in DNS, the NAPTR record is used for identifying available ways of contacting a specific node identified by that name. Specifically, it can be used for knowing what services exists for a specific domain name, including phone numbers by the use of the e164.arpa domain as described above.
对于DNS中的记录，NAPTR记录用于标识联系由该名称标识的特定节点的可用方式。具体而言，它可用于了解特定域名的服务，包括使用如上所述的e164.arpa域的电话号码。
The identification is using the NAPTR resource record defined for use in the URN resolution process, but it can be generalized in a way that suits the needs specified in this document.
标识使用为URN解析过程中使用而定义的NAPTR资源记录，但它可以以适合本文档中指定需求的方式进行概括。
It is the string which is the result of step 2 in section 2 above which is input to the NAPTR algorithm.
输入到NAPTR算法的是上面第2节中步骤2的结果字符串。
The key fields in the NAPTR RR are order, preference, service, flags, regexp, and replacement. For a detailed description, see:
NAPTR RR中的关键字段是顺序、首选项、服务、标志、regexp和替换。有关详细说明，请参阅：
o The order field specifies the order in which records MUST be processed when multiple NAPTR records are returned in response to a single query.
o order字段指定在响应单个查询返回多个NAPTR记录时必须处理记录的顺序。
o The preference field specifies the order in which records SHOULD be processed when multiple NAPTR records have the same value of "order".
o 首选项字段指定当多个NAPTR记录具有相同的“order”值时处理记录的顺序。
o The service field specifies the resolution protocol and resolution service(s) that will be available if the rewrite specified by the regexp or replacement fields is applied.
o 服务字段指定在应用regexp或replacement字段指定的重写时可用的解析协议和解析服务。
o The flags field contains modifiers that affect what happens in the next DNS lookup, typically for optimizing the process.
o flags字段包含影响下一个DNS查找中发生的情况的修饰符，通常用于优化流程。
o The regexp field is one of two fields used for the rewrite rules, and is the core concept of the NAPTR record.
o regexp字段是用于重写规则的两个字段之一，是NAPTR记录的核心概念。
o The replacement field is the other field that may be used for the rewrite rule.
o 替换字段是可用于重写规则的另一个字段。
Note that the client applies all the substitutions and performs all lookups, they are not performed in the DNS servers. Note that URIs are stored in the regexp field.
请注意，客户端应用所有替换并执行所有查找，而不是在DNS服务器中执行。请注意，URI存储在regexp字段中。
The input is an E.164 encoded telephone number. The output is a Uniform Resource Identifier in its absolute form according to the 'absoluteURI' production in the Collected ABNF found in RFC2396 [5]
输入是一个E.164编码的电话号码。根据RFC2396[5]中收集的ABNF中的“absoluteURI”结果，输出是绝对形式的统一资源标识符
An E.164 number, without any characters but leading '+' and digits, (result of step 2 in section 2 above) is the input to the NAPTR algorithm.
一个E.164数字，不带任何字符，但前导“+”和数字（上文第2节第2步的结果）是NAPTR算法的输入。
The service supported for a call is E2U.
呼叫支持的服务是E2U。
* Name: E.164 to URI * Mnemonic: E2U * Number of Operands: 1 * Type of Each Operand: First operand is an E.164 number. * Format of Each Operand: First operand is the E.164 number in the form as specified in step 2 in section 2 in this document. * Algorithm: Opaque * Output: One or more URIs * Error Conditions: o E.164 number not in the numbering plan o E.164 number in the numbering plan, but no URIs exist for that number o Service unavailable
* 名称：E.164到URI*助记符：E2U*操作数：1*每个操作数的类型：第一个操作数是E.164数字。*每个操作数的格式：第一个操作数是E.164数字，格式如本文件第2节第2步所述。*算法：不透明*输出：一个或多个URI*错误条件：o E.164编号不在编号计划中o E.164编号在编号计划中，但该编号不存在URI o服务不可用
* Security Considerations: o Malicious Redirection One of the fundamental dangers related to any service such as this is that a malicious entry in a resolver's database will cause clients to resolve the E.164 into the wrong URI. The possible intent may be to cause the client to retrieve a resource containing fraudulent or damaging material. o Denial of Service By removing the URI to which the E.164 maps, a malicious intruder may remove the client's ability to access the resource.
* 安全注意事项：恶意重定向与任何服务相关的一个基本危险是，解析程序数据库中的恶意条目将导致客户端将E.164解析为错误的URI。可能的意图可能是导致客户检索包含欺诈性或破坏性材料的资源。o拒绝服务通过删除E.164映射到的URI，恶意入侵者可能会删除客户端访问资源的能力。
This operation is used to map a one E.164 number to a list of URIs. The first well-known step in the resolution process is to remove all non-digits apart from the leading '+' from the E.164 number as described in step 1 and 2 in section 2 of this document.
此操作用于将一个E.164编号映射到URI列表。解析过程中的第一个众所周知的步骤是删除E.164编号中除前导“+”之外的所有非数字，如本文件第2节第1步和第2步所述。
$ORIGIN 4.3.2.1.6.7.9.8.6.4.e164.arpa. IN NAPTR 100 10 "u" "sip+E2U" "!^.*$!sip:info@tele2.se!" . IN NAPTR 102 10 "u" "mailto+E2U" "!^.*$!mailto:info@tele2.se!" .
$ORIGIN 4.3.2.1.6.7.9.8.6.4.e164.arpa。在NAPTR 100 10“u”sip+E2U“！^.*$！sip中：info@tele2.se!" . 在NAPTR 102 10“u”mailto+E2U“！^.*$！mailto中：info@tele2.se!" .
This describes that the domain 4.3.2.1.6.7.9.8.6.4.e164.arpa is preferably contacted by SIP, and secondly by SMTP.
这说明域4.3.2.1.6.7.9.8.6.4.e164.arpa最好通过SIP联系，其次通过SMTP联系。
In both cases, the next step in the resolution process is to use the resolution mechanism for each of the protocols, (SIP and SMTP) to know what node to contact for each.
在这两种情况下，解析过程的下一步是使用每个协议（SIP和SMTP）的解析机制来了解每个协议要联系的节点。
$ORIGIN 4.3.2.1.6.7.9.8.6.4.e164.arpa. IN NAPTR 10 10 "u" "sip+E2U" "!^.*$!sip:paf@swip.net!" . IN NAPTR 102 10 "u" "mailto+E2U" "!^.*$!mailto:paf@swip.net!" . IN NAPTR 102 10 "u" "tel+E2U" "!^.*$!tel:+4689761234!" .
$ORIGIN 4.3.2.1.6.7.9.8.6.4.e164.arpa。在NAPTR 10 10“u”sip+E2U“！^.*$！sip中：paf@swip.net!" . 在NAPTR 102 10“u”mailto+E2U“！^.*$！mailto中：paf@swip.net!" . 在NAPTR 102 10“u”中，电话+E2U”！^.*$！电话：+4689761234！”。
Note that the preferred method is to use the SIP protocol, but the result of the rewrite of the NAPTR record is a URI (the "u" flag in the NAPTR record). In the case of the protocol SIP, the URI might be a SIP URI, which is resolved as described in RFC 2543 [6]. In the case of the "tel" URI scheme [7], the procedure is restarted with this new E.164 number. The client is responsible for loop detection.
请注意，首选方法是使用SIP协议，但重写NAPTR记录的结果是URI（NAPTR记录中的“u”标志）。在协议SIP的情况下，URI可能是SIP URI，其解析如RFC 2543[6]中所述。在“tel”URI方案[7]的情况下，使用这个新的E.164号码重新启动该过程。客户端负责循环检测。
The rest of the resolution of the routing is done as described above.
路由解析的其余部分如上所述完成。
$ORIGIN 6.4.e164.arpa. * IN NAPTR 100 10 "u" "ldap+E2U" "!^+46(.*)$!ldap://ldap.se/cn=01!" .
$ORIGIN 6.4.e164.arpa.*在NAPTR 100 10“u”ldap+E2U“！^+46（.*）中！ldap://ldap.se/cn=01!" .
We see in this example that information about all E.164 numbers in the 46 countrycode (for Sweden) exists in an LDAP server, and the search to do is specified by the LDAP URI [8].
在本例中，我们看到关于46 countrycode（瑞典）中所有E.164号的信息都存在于LDAP服务器中，要执行的搜索由LDAP URI指定[8]。
This memo requests that the IANA delegate the E164.ARPA domain following instructions to be provided by the IAB. Names within this zone are to be delegated to parties according to the ITU recommendation E.164. The names allocated should be hierarchic in accordance with ITU Recommendation E.164, and the codes should assigned in accordance with that Recommendation.
本备忘录要求IANA按照IAB提供的指示委托E164.ARPA域。根据ITU建议E.164，该区域内的名称将委托给各方。分配的名称应按照ITU建议E.164的等级划分，代码应按照该建议分配。
Delegations in the zone e164.arpa (not delegations in delegated domains of e164.arpa) should be done after Expert Review, and the IESG will appoint a designated expert.
e164.arpa区域内的授权（不是e164.arpa授权域内的授权）应在专家审查后完成，IESG将任命一名指定专家。
As this system is built on top of DNS, one can not be sure that the information one get back from DNS is more secure than any DNS query. To solve that, the use of DNSSEC [9] for securing and verifying zones is to be recommended.
由于该系统是建立在DNS之上的，因此无法确保从DNS返回的信息比任何DNS查询都更安全。为了解决这个问题，建议使用DNSSEC[9]来保护和验证区域。
The caching in DNS can make the propagation time for a change take the same amount of time as the time to live for the NAPTR records in the zone that is changed. The use of this in an environment where IP-addresses are for hire (for example, when using DHCP [11]) must therefore be done very carefully.
DNS中的缓存可以使更改的传播时间与更改区域中NAPTR记录的生存时间相同。因此，在IP地址出租的环境中（例如，在使用DHCP[11]时），必须非常小心地使用此功能。
There are a number of countries (and other numbering environments) in which there are multiple providers of call routing and number/name-translation services. In these areas, any system that permits users, or putative agents for users, to change routing or supplier information may provide incentives for changes that are actually unauthorized (and, in some cases, for denial of legitimate change requests). Such environments should be designed with adequate mechanisms for identification and authentication of those requesting changes and for authorization of those changes.
许多国家（和其他编号环境）都有多家呼叫路由和号码/姓名翻译服务提供商。在这些领域，任何允许用户或假定的用户代理更改路由或供应商信息的系统都可能会为实际未经授权的更改（以及在某些情况下拒绝合法更改请求）提供激励。此类环境的设计应具有适当的机制，用于识别和验证请求变更的人以及授权这些变更。
Support and ideas have come from people at Ericsson, Bjorn Larsson and the group which implemented this scheme in their lab to see that it worked. Input has also come from ITU-T SG2, Working Party 1/2 (Numbering, Routing, Global Mobility and Service Definition), the ENUM working group in the IETF, John Klensin and Leif Sunnegardh.
爱立信、比约恩·拉尔森以及在实验室实施该计划以确保其有效性的小组的人员都提供了支持和想法。投入也来自ITU-T SG2、工作组1/2（编号、路由、全球移动和服务定义）、IETF中的ENUM工作组、John Klesins和Leif Sunnegardh。
References
工具书类
[1] Mealling, M. and R. Daniel, "The Naming Authority Pointer (NAPTR) DNS Resource Record", RFC 2915, September 2000.
[1] Mealling，M.和R.Daniel，“命名机构指针（NAPTR）DNS资源记录”，RFC 2915，2000年9月。
[2] Mockapetris, P., "Domain names - concepts and facilities", STD 13, RFC 1034, November 1987.
[2] Mockapetris，P.，“域名-概念和设施”，STD 13，RFC 1034，1987年11月。
[3] Mockapetris, P., "Domain names - implementation and specification", STD 13, RFC 1035, November 1987.
[3] Mockapetris，P.，“域名-实现和规范”，STD 13，RFC 10351987年11月。
[4] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
[4] Bradner，S.，“RFC中用于表示需求水平的关键词”，BCP 14，RFC 2119，1997年3月。
[5] Berners-Lee, T., Fielding, R.T. and L. Masinter, "Uniform Resource Identifiers (URI): Generic Syntax", RFC 2396, August 1998.
[5] Berners Lee，T.，Fielding，R.T.和L.Masinter，“统一资源标识符（URI）：通用语法”，RFC 2396，1998年8月。
[6] Handley, M., Schulzrinne, H., Schooler, E. and J. Rosenberg, "SIP: Session Initiation Protocol", RFC 2543, March 1999.
[6] Handley，M.，Schulzrinne，H.，Schooler，E.和J.Rosenberg，“SIP：会话启动协议”，RFC 25431999年3月。
[7] Vaha-Sipila, A., "URLs for Telephone Calls", RFC 2806, April 2000.
[7] Vaha Sipila，A.，“电话呼叫的URL”，RFC 2806，2000年4月。
[8] Howes, T. and M. Smith, "An LDAP URL Format", RFC 1959, June 1996.
[8] Howes，T.和M.Smith，“LDAP URL格式”，RFC19591996年6月。
[9] Eastlake, D., "Domain Name System Security Extensions", RFC 2535, March 1999.
[9] Eastlake，D.，“域名系统安全扩展”，RFC 25351999年3月。
[10] Gulbrandsen, A., Vixie, P. and L. Esibov, "A DNS RR for specifying the location of services (DNS SRV)", RFC 2782, February 2000.
[10] Gulbrandsen，A.，Vixie，P.和L.Esibov，“用于指定服务位置（DNS SRV）的DNS RR”，RFC 2782，2000年2月。
[11] Droms, R., "Dynamic Host Configuration Protocol", RFC 2131, March 1997.
[11] Droms，R.，“动态主机配置协议”，RFC 2131，1997年3月。
Author's Address
作者地址
Patrik Faltstrom Cisco Systems Inc 170 W Tasman Drive SJ-13/2 San Jose CA 95134 USA
Patrik Faltstrom Cisco Systems Inc 170 W塔斯曼大道SJ-13/2美国加利福尼亚州圣何塞95134
EMail: paf@cisco.com
URI: http://www.cisco.com
EMail: paf@cisco.com
URI: http://www.cisco.com
Say that the content of the e164.arpa zone is the following:
假设e164.arpa区域的内容如下：
$ORIGIN e164.arpa. 6.4 IN NS ns.regulator-e164.example.se.
$ORIGIN e164.arpa。6.4在NS NS.regulator-e164.example.se中。
The regulator has in turn given a series of 10000 numbers to the telco with the name Telco-A. The regulator because of that has in his DNS.
监管机构又向电信公司提供了一系列10000个编号，名称为telco-a。因此，监管机构在其DNS中保留了该编号。
$ORIGIN 6.4.e164.arpa. 6.7.9.8 IN NS ns.telco-a.example.se.
$ORIGIN 6.4.e164.arpa。6.7.9.8在NS NS.telco-a.example.se中。
A user named Sven Svensson has from Telco A got the phone number +46-8-9761234. The user gets the service of running DNS from the company Redirection Service. Sven Svensson has asked Telco A to point out Redirection Service as the authoritative source for information about the number +46-8-9761234. Telco A because of this puts in his DNS the following.
一位名叫Sven Svensson的用户从电信A获得了电话号码+46-8-9761234。用户从公司重定向服务获得运行DNS的服务。Sven Svensson已要求电信A指出重定向服务是有关+46-8-9761234号的权威信息来源。电信A因此在其DNS中放入以下内容。
$ORIGIN 6.7.9.8.6.4.e164.arpa. 4.3.2.1 IN NS ns.redirection-service.example.se.
$ORIGIN 6.7.9.8.6.4.e164.arpa。4.3.2.1在NS.redirection-service.example.se中。
Sven Svensson has already plain telephony from Telco A, but also a SIP service from the company Sip Service which provides Sven with the SIP URI "sip:sven@sips.se". The ISP with the name ISP A runs email and webpages for Sven, under the email address sven@ispa.se, and URI http://svensson.ispa.se.
Sven Svensson已经拥有来自电信公司A的普通电话，还拥有来自公司SIP服务的SIP服务，该公司为Sven提供SIP URI“SIP:sven@sips.se". 名为ISP A的ISP在电子邮件地址下为Sven运行电子邮件和网页sven@ispa.se，和URIhttp://svensson.ispa.se.
The DNS for the redirection service because of this contains the following.
因此，重定向服务的DNS包含以下内容。
$ORIGIN 4.3.2.1.6.7.9.8.6.4.e164.arpa. IN NAPTR 10 10 "u" "sip+E2U" "!^.*$!sip:sven@sips.se!" . IN NAPTR 10 10 "u" "mailto+E2U" "!^.*$!mailto:sven@ispa.se!" . IN NAPTR 10 10 "u" "http+E2U" "!^.*$!http://svensson.ispa.se!" . IN NAPTR 10 10 "u" "tel+E2U" "!^.*$!tel:+46-8-9761234!" .
$ORIGIN 4.3.2.1.6.7.9.8.6.4.e164.arpa。在NAPTR 10 10“u”sip+E2U“！^.*$！sip中：sven@sips.se!" . 在NAPTR 10 10“u”mailto+E2U”！^.*$！mailto中：sven@ispa.se!" . 在NAPTR 10 10“u”http+E2U“！^.*$中！http://svensson.ispa.se!" . 在NAPTR 10 10“u”中，电话+E2U”！^.*$！电话：+46-8-9761234！”。
A user, John Smith, want to contact Sven Svensson, he to start with only has the E.164 number of Sven, i.e. +46-8-9761234. He takes the number, and enters the number in his communication client, which happen to know how to handle the SIP protocol. The client removes the dashes, and ends up with the E.164 number +4689761234. That is what is used in the algorithm for NAPTR records, which is as follows.
用户John Smith希望联系Sven Svensson，他首先只有Sven的E.164号码，即+46-8-9761234。他取下这个号码，然后在他的通信客户端中输入这个号码，这个客户端碰巧知道如何处理SIP协议。客户端删除破折号，并以E.164编号+4689761234结束。这就是NAPTR记录算法中使用的内容，如下所示。
The client converts the E.164 number into the domain name 4.3.2.1.6.7.9.8.6.4.e164.arpa., and queries for NAPTR records for this domainname. Using DNS mechanisms which includes following the NS record referrals, the following records are returned:
客户端将E.164号转换为域名4.3.2.1.6.7.9.8.6.4.e164.arpa.，并查询此域名的NAPTR记录。使用包括以下NS记录引用的DNS机制，将返回以下记录：
$ORIGIN 4.3.2.1.6.7.9.8.6.4.e164.arpa. IN NAPTR 10 10 "u" "sip+E2U" "!^.*$!sip:sven@sips.se" . IN NAPTR 10 10 "u" "mailto+E2U" "!^.*$!mailto:sven@ispa.se" . IN NAPTR 10 10 "u" "http+E2U" "!^.*$!http://svensson.ispa.se" . IN NAPTR 10 10 "u" "tel+E2U" "!^.*$!tel:+46-8-9761234" .
$ORIGIN 4.3.2.1.6.7.9.8.6.4.e164.arpa。在NAPTR 10 10“u”sip+E2U“！^.*$！sip中：sven@sips.se" . 在NAPTR 10 10“u”mailto+E2U”！^.*$！mailto中：sven@ispa.se" . 在NAPTR 10 10“u”http+E2U“！^.*$中！http://svensson.ispa.se" . 在NAPTR 10 10“u”中，电话+E2U”！^.*$！电话：+46-8-9761234”。
Because the client knows sip, the first record above is selected, and the regular expression "!^.*$!sip:sven@sips.se" is applied to the original string, "+4689761234". The output is "sip:sven@sips.se" which is used according to SIP resolution.
因为客户端知道sip，所以选择上面的第一条记录，并使用正则表达式“！^.*$！sip:sven@sips.se应用于原始字符串“+4689761234”。输出为“sip:sven@sips.se“根据SIP决议使用。
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