Network Working Group M. Foster
Request for Comments: 3482 T. McGarry
Category: Informational J. Yu
NeuStar, Inc.
February 2003
Network Working Group M. Foster
Request for Comments: 3482 T. McGarry
Category: Informational J. Yu
NeuStar, Inc.
February 2003
Number Portability in the Global Switched Telephone Network (GSTN): An Overview
全球交换电话网（GSTN）中的号码可携性：概述
Status of this Memo
本备忘录的状况
This memo provides information for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited.
本备忘录为互联网社区提供信息。它没有规定任何类型的互联网标准。本备忘录的分发不受限制。
Copyright Notice
版权公告
Copyright (C) The Internet Society (2003). All Rights Reserved.
版权所有（C）互联网协会（2003年）。版权所有。
Abstract
摘要
This document provides an overview of E.164 telephone number portability (NP) in the Global Switched Telephone Network (GSTN). NP is a regulatory imperative seeking to liberalize local telephony service competition, by enabling end-users to retain telephone numbers while changing service providers. NP changes the fundamental nature of a dialed E.164 number from a hierarchical physical routing address to a virtual address, thereby requiring the transparent translation of the later to the former. In addition, there are various regulatory constraints that establish relevant parameters for NP implementation, most of which are not network technology specific. Consequently, the implementation of NP behavior consistent with applicable regulatory constraints, as well as the need for interoperation with the existing GSTN NP implementations, are relevant topics for numerous areas of IP telephony works-in-progress with the IETF.
本文件概述了全球交换电话网（GSTN）中的E.164电话号码可移植性（NP）。NP是一项法规要求，旨在通过允许最终用户在更换服务提供商的同时保留电话号码，实现本地电话服务竞争的自由化。NP将拨打的E.164号码的基本性质从分层物理路由地址更改为虚拟地址，因此需要将后者透明地转换为前者。此外，还存在各种监管约束，这些约束为NP实施确定了相关参数，其中大多数并非特定于网络技术。因此，与适用的监管约束一致的NP行为的实施，以及与现有GSTN NP实施互操作的需要，是IETF正在进行的IP电话工作的许多领域的相关主题。
Table of Contents
目录
1. Introduction ................................................. 2
2. Abbreviations and Acronyms ................................... 4
3. Types of Number Portability .................................. 6
4. Service Provider Number Portability Schemes .................. 7
4.1 All Call Query (ACQ) ................................... 8
4.2 Query on Release (QoR) ................................. 9
4.3 Call Dropback .......................................... 10
4.4 Onward Routing (OR) .................................... 11
4.5 Comparisons of the Four Schemes ........................ 11
5. Database Queries in the NP Environment ....................... 13
5.1 U.S. and Canada ........................................ 13
5.2 Europe ................................................. 14
6. Call Routing in the NP Environment ........................... 15
6.1 U.S. and Canada ........................................ 16
6.2 Europe ................................................. 17
7. NP Implementations for Geographic E.164 Numbers .............. 19
8. Number Conservation Method Enabled By NP ..................... 22
8.1 Block Pooling .......................................... 22
8.2 ITN Pooling ............................................ 23
9. Potential Implications ....................................... 23
10. Security Considerations ...................................... 27
11. IANA Considerations .......................................... 27
12. Normative References ......................................... 27
13. Informative References ....................................... 28
14. Acknowledgement .............................................. 29
15. Authors' Addresses ........................................... 29
16. Full Copyright Statement ..................................... 30
1. Introduction ................................................. 2
2. Abbreviations and Acronyms ................................... 4
3. Types of Number Portability .................................. 6
4. Service Provider Number Portability Schemes .................. 7
4.1 All Call Query (ACQ) ................................... 8
4.2 Query on Release (QoR) ................................. 9
4.3 Call Dropback .......................................... 10
4.4 Onward Routing (OR) .................................... 11
4.5 Comparisons of the Four Schemes ........................ 11
5. Database Queries in the NP Environment ....................... 13
5.1 U.S. and Canada ........................................ 13
5.2 Europe ................................................. 14
6. Call Routing in the NP Environment ........................... 15
6.1 U.S. and Canada ........................................ 16
6.2 Europe ................................................. 17
7. NP Implementations for Geographic E.164 Numbers .............. 19
8. Number Conservation Method Enabled By NP ..................... 22
8.1 Block Pooling .......................................... 22
8.2 ITN Pooling ............................................ 23
9. Potential Implications ....................................... 23
10. Security Considerations ...................................... 27
11. IANA Considerations .......................................... 27
12. Normative References ......................................... 27
13. Informative References ....................................... 28
14. Acknowledgement .............................................. 29
15. Authors' Addresses ........................................... 29
16. Full Copyright Statement ..................................... 30
This document provides an overview of E.164 telephone number [E164] portability in the Global Switched Telephone Network (GSTN). There are considered to be three types of number portability (NP): service provider number portability (SPNP), location portability (not to be confused with terminal mobility), and service portability.
本文档概述了全球交换电话网络（GSTN）中E.164电话号码[E164]的可移植性。有三种类型的号码可移植性（NP）：服务提供商号码可移植性（SPNP）、位置可移植性（不要与终端移动性混淆）和服务可移植性。
SPNP, the focus of the present document, is a regulatory imperative in many countries seeking to liberalize telephony service competition, especially local service. Historically, local telephony service (as compared to long distance or international service) has been regulated as a utility-like form of service. While a number of countries had begun liberalization (e.g., privatization, de-regulation, or re-regulation) some years ago, the advent of NP is relatively recent (since ~1995).
SPNP是本文件的重点，在许多寻求开放电话服务竞争，特别是本地服务的国家，是一项法规要求。从历史上看，本地电话服务（与长途或国际服务相比）一直被视为一种类似于公用事业的服务形式。虽然一些国家在几年前就开始了自由化（例如私有化、去监管或重新监管），但NP的出现相对较晚（自1995年）。
E.164 numbers can be non-geographic and geographic numbers. Non-geographic numbers do not reveal the location information of those numbers. Geographic E.164 numbers were intentionally designed as hierarchical routing addresses which could systematically be digit-analyzed to ascertain the country, serving network provider, serving end-office switch, and specific line of the called party. As such, without NP a subscriber wishing to change service providers would incur a number change as a consequence of being served off of a different end-office switch operated by the new service provider. The impact in cost and convenience to the subscriber of changing numbers is seen as a barrier to competition. Hence NP has become associated with GSTN infrastructure enhancements associated with a competitive environment driven by regulatory directives.
E.164数字可以是非地理数字和地理数字。非地理数字不会显示这些数字的位置信息。地理E.164号码有意设计为分层路由地址，可对其进行系统的数字分析，以确定国家、服务网络提供商、服务终端局交换机和被叫方的特定线路。因此，在没有NP的情况下，希望更换服务提供商的订户将由于被新服务提供商操作的不同终端局交换机服务而导致号码变化。改变号码对用户的成本和便利性的影响被视为竞争的障碍。因此，NP已与GSTN基础设施增强联系在一起，这与监管指令驱动的竞争环境有关。
Forms of SPNP have been deployed or are being deployed widely in the GSTN in various parts of the world, including the U.S., Canada, Western Europe, Australia, and the Pacific Rim (e.g., Hong Kong). Other regions, such as South America (e.g., Brazil), are actively considering it.
在全球各地，包括美国、加拿大、西欧、澳大利亚和环太平洋地区（如香港），GSTN已部署或正在广泛部署各种形式的SPNP。其他区域，如南美洲（如巴西），正在积极考虑这一问题。
Implementation of NP within a national telephony infrastructure entails potentially significant changes to numbering administration, network element signaling, call routing and processing, billing, service management, and other functions.
在国家电话基础设施内实施NP可能会对编号管理、网元信令、呼叫路由和处理、计费、服务管理和其他功能产生重大变化。
NP changes the fundamental nature of a dialed E.164 number from a hierarchical physical routing address to a virtual address. NP implementations attempt to encapsulate the impact to the GSTN and make NP transparent to subscribers by incorporating a translation function to map a dialed, potentially ported E.164 address, into a network routing address (either a number prefix or another E.164 address) which can be hierarchically routed.
NP将拨号E.164号码的基本性质从分层物理路由地址更改为虚拟地址。NP实现试图封装对GSTN的影响，并通过合并转换功能将拨号的、可能移植的E.164地址映射到可以分层路由的网络路由地址（数字前缀或另一个E.164地址），使NP对订阅者透明。
This is roughly analogous to the use of network address translation on IP is that enables IP address portability by containing the address change to the edge of the network and retain the use of Classless Inter-Domain Routing (CIDR) blocks in the core which can be route aggregated by the network service provider to the rest of the internet.
这大致类似于在IP上使用网络地址转换，即通过包含到网络边缘的地址更改来实现IP地址可移植性，并在核心中保留使用无类域间路由（CIDR）块，该块可由网络服务提供商路由聚合到internet的其余部分。
NP bifurcates the historical role of a subscriber's E.164 address into two or more data elements (a dialed or virtual address, and a network routing address) that must be made available to network elements through an NP translation database, carried by forward call signaling, and recorded on call detail records. Not only is call processing and routing affected, but also Signaling System Number 7 (SS7)/Common Channel Signaling System Number 7 (C7) messaging. A number of Transaction Capabilities Application Part (TCAP)-based SS7
NP将用户的E.164地址的历史角色分为两个或多个数据元素（拨号或虚拟地址，以及网络路由地址），这些数据元素必须通过NP翻译数据库提供给网络元素，由前向呼叫信令承载，并记录呼叫详细记录。不仅影响呼叫处理和路由，还影响信令系统7号（SS7）/公共信道信令系统7号（C7）消息传递。基于应用程序部分（TCAP）的大量事务处理功能SS7
messaging sets utilize an E.164 address as an application-level network element address in the global title address (GTA) field of the Signaling Connection Control Part (SCCP) message header. Consequently, SS7/C7 signaling transfer points (STPs) and gateways need to be able to perform n-digit global title translation (GTT) to translate a dialed E.164 address into its network address counterpart via the NP database.
消息传递集利用E.164地址作为信令连接控制部分（SCCP）消息头的全局标题地址（GTA）字段中的应用级网元地址。因此，SS7/C7信令传输点（STP）和网关需要能够执行n位全局标题转换（GTT），以便通过NP数据库将拨号的E.164地址转换为其对应的网络地址。
In addition, there are various national regulatory constraints that establish relevant parameters for NP implementation, most of which are not network technology specific. Consequently, implementations of NP behavior in IP telephony, consistent with applicable regulatory constraints, as well as the need for interoperation with the existing GSTN NP implementations, are relevant topics for numerous areas of IP telephony works-in-progress with the IETF.
此外，存在各种国家监管约束，这些约束为NP实施确定了相关参数，其中大多数并非特定于网络技术。因此，IP电话中NP行为的实现，符合适用的监管约束，以及与现有GSTN NP实现互操作的需要，是IETF正在进行的IP电话工作的许多领域的相关主题。
This document describes three types of number portability and the four schemes that have been standardized to support SPNP for geographic E.164 numbers specifically. Following that, specific information regarding the call routing and database query implementations are described for several regions (North American and Europe) and industries (wireless vs. wireline). The Number Portability Database (NPDB) interfaces and the call routing schemes that are used in North America and Europe are described to show the variety of standards that may be implemented worldwide. A glance at the NP implementations worldwide is provided. Number pooling is briefly discussed to show how NP is being enhanced in the U.S. to conserve North American area codes. The conclusion briefly touches the potential impacts of NP on IP and Telecommunications Interoperability.
本文件描述了三种类型的号码可移植性和四种已标准化的方案，以支持地理E.164号码的SPNP。随后，描述了几个地区（北美和欧洲）和行业（无线与有线）关于呼叫路由和数据库查询实现的具体信息。描述了北美和欧洲使用的号码可移植性数据库（NPDB）接口和呼叫路由方案，以显示可能在全球实施的各种标准。本文简要介绍了全球范围内的NP实现。简要讨论了号码池，以说明美国如何增强NP以保护北美区号。结论简要涉及了NP对IP和电信互操作性的潜在影响。
ACQ All Call Query AIN Advanced Intelligent Network AMPS Advanced Mobile Phone System ANSI American National Standards Institute API Application Programming Interface C7 Common Channel Signaling System Number 7 CDMA Code Division Multiple Access CdPA Called Party Address CdPN Called Party Number CH Code Holder CIC Carrier Identification Code CIDR Classless Inter-Domain Routing CMIP Common Management Information Protocol CO Central Office CS1 Capability Set 1
ACQ All Call Query AIN高级智能网AMPS高级移动电话系统ANSI美国国家标准协会API应用编程接口C7公共信道信令系统7号CDMA码分多址CdPA被叫方地址CdPN被叫方号码CH码持有者CIC载波识别码CIDR无类别域间路由CMIP公共管理信息协议CO中央局CS1能力集1
CS2 Capability Set 2 DN Directory Number DNS Domain Name System ENUM Telephone Number Mapping ETSI European Tecommunications Standards Institute FCI Forward Call Indicator GAP Generic Address Parameter GMSC Gateway Mobile Services Switching Center or Gateway Mobile Switching Center GNP Geographic Number Portability GSM Global System for Mobile Communications GSTN Global Switched Telephone Network GTT Global Title Translation GW Gateways HLR Home Location Register IAM Initial Address Message IETF Internet Engineering Task Force ILNP Interim LNP IN Intelligent Network INAP Intelligent Network Application Part INP Interim NP IP Internet Protocol IS-41 Interim Standards Number 41 ISDN Integrated Services Digital Network ISUP ISDN User Part ITN Individual Telephony Number ITU International Telecommunication Union ITU-TS ITU-Telecommunication Sector LDAP Lightweight Directory Access Protocol LEC Local Exchange Carrier LERG Local Exchange Routing Guide LNP Local Number Portability LRN Location Routing Number MAP Mobile Application Part MNP Mobile Number Portability MSRN Mobile Station Roaming Number MTP Message Transfer Part NANP North American Numbering Plan NGNP Non-Geographic Number Portability NOA Nature of Address NP Number Portability NPA Numbering Plan Area NPDB Number Portability Database NRN Network Routing Number OR Onward Routing OSS Operation Support System PCS Personal Communication Services PNTI Ported Number Translation Indicator
CS2能力集2 DN目录号DNS域名系统枚举电话号码映射ETSI欧洲通信标准协会FCI前向呼叫指示器GAP通用地址参数GMSC网关移动服务交换中心或网关移动交换中心GNP地理号码可移植性GSM全球移动系统通信GSTN全球交换电话网GTT全球标题翻译GW网关HLR归属位置寄存器IAM初始地址消息IETF互联网工程任务组ILNP智能网中的临时LNP INAP智能网应用部分INP临时NP IP互联网协议IS-41临时标准编号41 ISDN综合业务数字网ISUP ISDN用户部分ITN个人电话号码ITU国际电信联盟ITU-TS ITU电信部门LDAP轻型目录访问协议LEC本地交换载波LERG本地交换路由指南LNP本地号码可移植性LRN位置路由号码地图移动应用部分MNP移动号码可移植性MSRN移动台漫游号码MTP报文传输部分NANP北美编号计划NGNP非地理号码可移植性NOA地址性质NP号码可移植性NPA编号计划区域NPDB号码可移植性数据库NRN网络路由号码或转发路由OSS操作支持系统PC个人通信服务PNTI端口号码转换指示器
PODP Public Office Dialing Plan PUC Public Utility Commission QoR Query on Release RN Routing Number RTP Return to Pivot SCCP Signaling Connection Control Part SCP Service Control Point SIP Session Initiation Protocol SMR Special Mobile Radio SPNP Service Provider Number Portability SRF Signaling Relaying Function SRI Send Routing Information SS7 Signaling System Number 7 STP Signaling Transfer Point TCAP Transaction Capabilities Application Part TDMA Time Division Multiple Access TN Telephone Number TRIP Telephony Routing Information Protocol URL Universal Resource Locator U.S. United States
PODP公共办公室拨号计划PUC公用事业委员会QoR查询发布RN路由号码RTP返回枢轴SCCP信令连接控制部分SCP服务控制点SIP会话发起协议SMR专用移动无线电SPNP服务提供商号码可移植性SRF信令中继功能SRI发送路由信息SS7信令系统7号STP信令转接点TCAP事务处理能力应用部分TDMA时分多址TN电话号码行车电话路由信息协议URL通用资源定位器美国
As there are several types of E.164 numbers (telephone numbers, or just TN) in the GSTN, there are correspondingly several types of E.164 NP in the GSTN. First there are so-called non-geographic E.164 numbers, commonly used for service-specific applications such as freephone (800 or 0800). Portability of these numbers is called non-geographic number portability (NGNP). NGNP, for example, was deployed in the U.S. in 1986-92.
由于GSTN中有几种类型的E.164号码（电话号码，或仅TN），因此GSTN中相应地有几种类型的E.164 NP。首先是所谓的非地理E.164号码，通常用于特定于服务的应用程序，如freephone（800或0800）。这些号码的可移植性称为非地理号码可移植性（NGNP）。例如，NGNP于1986-1992年部署在美国。
Geographic number portability (GNP), which includes traditional fixed or wireline numbers, as well as mobile numbers which are allocated out of geographic number range prefixes, is called NP or GNP, or in the U.S. local number portability (LNP).
地理号码可移植性（GNP）包括传统的固定或有线号码，以及在地理号码范围前缀之外分配的移动号码，称为NP或GNP，或在美国本地号码可移植性（LNP）中。
Number portability allows the telephony subscribers in the GSTN to keep their phone numbers when they change their service providers or subscribed services, or when they move to a new location.
号码可移植性允许GSTN中的电话用户在更改其服务提供商或订阅的服务或移动到新位置时保留其电话号码。
The ability to change the service provider while keeping the same phone number is called service provider portability (SPNP), also known as "operator portability."
在保持相同电话号码的同时更改服务提供商的能力称为服务提供商可移植性（SPNP），也称为“运营商可移植性”
The ability to change the subscriber's fixed service location while keeping the same phone number is called location portability.
在保持相同电话号码的同时更改用户的固定服务位置的能力称为位置可移植性。
The ability to change the subscribed services (e.g., from the plain
更改订阅服务的能力（例如，从普通
old telephone service to Integrated Services Digital Network (ISDN) services) while keeping the same phone number is called service portability. Another aspect of service portability is to allow the subscribers to enjoy the subscribed services in the same way when they roam outside their home networks, as is supported by the cellular/wireless networks.
旧的电话业务向综合业务数字网（ISDN）业务转变，同时保持相同的电话号码，称为业务可移植性。服务可移植性的另一个方面是允许订户在其家庭网络之外漫游时以相同的方式享受预订的服务，这是由蜂窝/无线网络支持的。
In addition, mobile number portability (MNP) refers to specific NP implementation in mobile networks, either as part of a broader NP implementation in the GSTN or on a stand-alone basis. Where interoperation of LNP and MNP is supported, service portability between fixed and mobile service types is possible.
此外，移动号码可移植性（MNP）指的是移动网络中的特定NP实现，作为GSTN中更广泛的NP实现的一部分，或者是在独立的基础上。在支持LNP和MNP互操作的情况下，固定和移动服务类型之间的服务可移植性是可能的。
At present, SPNP has been the primary form of NP deployed due to its relevance in enabling local service competition.
目前，SPNP已成为部署NP的主要形式，因为它在促进本地服务竞争方面具有相关性。
Also in use in the GSTN are the terms interim NP (INP) or Interim LNP (ILNP) and true NP. Interim NP usually refers to the use of remote call forwarding-like measures to forward calls to ported numbers through the donor network to the new service network. These are considered interim relative to true NP, which seeks to remove the donor network or old service provider from the call or signaling path altogether. Often the distinction between interim and true NP is a national regulatory matter relative to the technical/operational requirements imposed on NP in that country.
GSTN中使用的术语还有过渡NP（INP）或过渡LNP（ILNP）和真实NP。临时NP通常指使用类似远程呼叫转发的措施，通过施主网络将呼叫转发到端口号码到新的服务网络。这些被认为是相对于真正的NP的过渡，后者寻求从呼叫或信令路径中完全移除施主网络或旧的服务提供商。通常，临时和真实NP之间的区别是与该国对NP施加的技术/操作要求相关的国家监管事项。
Implementations of true NP in certain countries (e.g., U.S., Canada, Spain, Belgium, Denmark) may pose specific requirements for IP telephony implementations as a result of regulatory and industry requirements for providing call routing and signaling independent of the donor network or last previous serving network.
在某些国家（如美国、加拿大、西班牙、比利时、丹麦）实施真正的NP可能会对IP电话实施提出具体要求，这是独立于施主网络或上一个服务网络提供呼叫路由和信令的监管和行业要求的结果。
Four schemes can be used to support service provider portability and are briefly described below. But first, some further terms are introduced.
四种方案可用于支持服务提供商的可移植性，下面将简要介绍。但首先，引入了一些进一步的术语。
The donor network is the network that first assigned a telephone number (e.g., TN +1-202-533-1234) to a subscriber, out of a number range administratively (e.g., +1 202-533) assigned to it. The current service provider (new SP), or new serving network, is the network that currently serves the ported number. The old serving network (or old SP) is the network that previously served the ported number before the number was ported to the new serving network. Since a TN can port a number of times, the old SP is not necessarily the same as the donor network, except for the first time the TN ports away, or when the TN ports back into the donor network and away
施主网络是首先将电话号码（例如，TN+1-202-533-1234）分配给用户的网络，超出了管理上分配给它的号码范围（例如，+1 202-533）。当前服务提供商（新SP）或新服务网络是当前为端口号提供服务的网络。旧服务网络（或旧SP）是在将端口号移植到新服务网络之前，先前为该端口号提供服务的网络。由于TN可以多次进行端口连接，因此旧SP不一定与施主网络相同，除了第一次TN端口离开，或者当TN端口返回施主网络并离开时
again. While the new SP and old SP roles are transitory as a TN ports around, the donor network is always the same for any particular TN based on the service provider to whom the subtending number range was administratively assigned. See the discussion below on number pooling, as this enhancement of NP further bifurcates the role of the donor network into two (the number range or code holder network, and the block holder network).
再一次虽然新SP和旧SP角色作为TN端口是暂时的，但基于管理分配给其子终端号码范围的服务提供商，任何特定TN的施主网络始终相同。请参阅下面关于号码池的讨论，因为NP的这一增强将施主网络的角色进一步分为两部分（号码范围或代码持有者网络，以及区块持有者网络）。
To simplify the illustration, all the transit networks are ignored. The originating or donor network is the one that performs the database queries or call redirection, and the dialed directory number (TN) has previously been ported out of the donor network.
为了简化说明，忽略了所有公交网络。发起网络或施主网络是执行数据库查询或呼叫重定向的网络，拨号目录号（TN）以前已从施主网络中移植出来。
It is assumed that the old serving network, the new serving network, and the donor network are different networks so as to show which networks are involved in call handling and routing and database queries in each of the four schemes. Please note that the port of the number (process of moving it from one network to another) happened prior to the call setup and is not included in the call steps. Information carried in the signaling messages to support each of the four schemes is not discussed to simplify the explanation.
假设旧的服务网络、新的服务网络和施主网络是不同的网络，以显示在四种方案中，哪些网络参与呼叫处理、路由和数据库查询。请注意，号码的端口（从一个网络移动到另一个网络的过程）发生在呼叫设置之前，不包括在呼叫步骤中。为了简化解释，不讨论支持四种方案中的每一种方案的信令消息中携带的信息。
Figure 1 shows the call steps for the ACQ scheme. Those call steps are as follows:
图1显示了ACQ方案的调用步骤。这些调用步骤如下所示：
1) The Originating Network receives a call from the caller and sends a query to a centrally administered Number Portability Database (NPDB), a copy of which is usually resident on a network element within its network or through a third party provider.
1) 发起网络接收来自呼叫者的呼叫并向中央管理的号码可移植性数据库（NPDB）发送查询，NPDB的副本通常驻留在其网络内的网元上或通过第三方提供商。
2) The NPDB returns the routing number associated with the dialed directory number. The routing number is discussed later in Section 6.
2) NPDB返回与所拨目录号关联的路由号码。下文第6节将讨论路由编号。
3) The Originating Network uses the routing number to route the call to the new serving network.
3) 发起网络使用路由号码将呼叫路由到新的服务网络。
+-------------+ +-----------+ Number +-----------+
| Centralized | | New Serv. | ported | Old Serv. |
| NPDB | +-------->| Network |<------------| Network |
+-------------+ | +-----------+ +-----------+
^ | |
| | |
1| | 3.|
| | 2. |
| | |
| v |
+----------+ | +----------+ +----------+
| Orig. |------+ | Donor | | Internal |
| Network | | Network | | NPDB |
+----------+ +----------+ +----------+
+-------------+ +-----------+ Number +-----------+
| Centralized | | New Serv. | ported | Old Serv. |
| NPDB | +-------->| Network |<------------| Network |
+-------------+ | +-----------+ +-----------+
^ | |
| | |
1| | 3.|
| | 2. |
| | |
| v |
+----------+ | +----------+ +----------+
| Orig. |------+ | Donor | | Internal |
| Network | | Network | | NPDB |
+----------+ +----------+ +----------+
Figure 1 - All Call Query (ACQ) Scheme.
图1-所有呼叫查询（ACQ）方案。
Figure 2 shows the call steps for the QoR scheme. Those call steps are as follows:
图2显示了QoR方案的调用步骤。这些调用步骤如下所示：
+-------------+ +-----------+ Number +-----------+
| Centralized | | New Serv. | ported | Old Serv. |
| NPDB | | Network |<------------| Network |
+-------------+ +-----------+ +-----------+
^ | ^
| | 4. |
3.| | 5. |
| | +----------------------+
| | |
| v |
+----------+ 2. +----------+ +----------+
| Orig. |<---------------| Donor | | Internal |
| Network |--------------->| Network | | NPDB |
+----------+ 1. +----------+ +----------+
+-------------+ +-----------+ Number +-----------+
| Centralized | | New Serv. | ported | Old Serv. |
| NPDB | | Network |<------------| Network |
+-------------+ +-----------+ +-----------+
^ | ^
| | 4. |
3.| | 5. |
| | +----------------------+
| | |
| v |
+----------+ 2. +----------+ +----------+
| Orig. |<---------------| Donor | | Internal |
| Network |--------------->| Network | | NPDB |
+----------+ 1. +----------+ +----------+
Figure 2 - Query on Release (QoR) Scheme.
图2-发布查询（QoR）方案。
1) The Originating Network receives a call from the caller and routes the call to the donor network.
1) 发起网络接收来自呼叫者的呼叫并将呼叫路由到施主网络。
2) The donor network releases the call and indicates that the dialed directory number has been ported out of that switch.
2) 施主网络将释放呼叫，并指示已从该交换机中导出所拨打的目录号。
3) The Originating Network sends a query to its copy of the centrally administered NPDB.
3) 发起网络向其集中管理的NPDB副本发送查询。
4) The NPDB returns the routing number associated with the dialed directory number.
4) NPDB返回与所拨目录号关联的路由号码。
5) The Originating Network uses the routing number to route the call to the new serving network.
5) 发起网络使用路由号码将呼叫路由到新的服务网络。
Figure 3 shows the call steps for the Dropback scheme. This scheme is also known as "Return to Pivot (RTP)." Those call steps are as follows:
图3显示了Dropback方案的调用步骤。此方案也称为“返回到枢轴（RTP）”。这些调用步骤如下所示：
1) The Originating Network receives a call from the caller and routes the call to the donor network.
1) 发起网络接收来自呼叫者的呼叫并将呼叫路由到施主网络。
2) The donor network detects that the dialed directory number has been ported out of the donor switch and checks with an internal network-specific NPDB.
2) 施主网络检测到拨出的目录号已从施主交换机中导出，并与内部网络特定的NPDB进行检查。
3) The internal NPDB returns the routing number associated with the dialed directory number.
3) 内部NPDB返回与所拨目录号关联的路由号码。
4) The donor network releases the call by providing the routing number.
4) 施主网络通过提供路由号码来释放呼叫。
5) The Originating Network uses the routing number to route the call to the new serving network.
5) 发起网络使用路由号码将呼叫路由到新的服务网络。
+-------------+ +-----------+ Number +-----------+
| Centralized | | New Serv. | porting | Old Serv. |
| NPDB | | Network |<------------| Network |
+-------------+ +-----------+ +-----------+
/\
|
5. |
+------------------------+
|
|
+----------+ 4. +----------+ 3. +----------+
| Orig. |<---------------| Donor |<----------| Internal |
| Network |--------------->| Network |---------->| NPDB |
+----------+ 1. +----------+ 2. +----------+
+-------------+ +-----------+ Number +-----------+
| Centralized | | New Serv. | porting | Old Serv. |
| NPDB | | Network |<------------| Network |
+-------------+ +-----------+ +-----------+
/\
|
5. |
+------------------------+
|
|
+----------+ 4. +----------+ 3. +----------+
| Orig. |<---------------| Donor |<----------| Internal |
| Network |--------------->| Network |---------->| NPDB |
+----------+ 1. +----------+ 2. +----------+
Figure 3 - Dropback Scheme.
图3-回退方案。
Figure 4 shows the call steps for the OR scheme. Those call steps are as follows:
图4显示了OR方案的调用步骤。这些调用步骤如下所示：
1) The Originating Network receives a call from the caller and routes the call to the donor network.
1) 发起网络接收来自呼叫者的呼叫并将呼叫路由到施主网络。
2) The donor network detects that the dialed directory number has been ported out of the donor switch and checks with an internal network-specific NPDB.
2) 施主网络检测到拨出的目录号已从施主交换机中导出，并与内部网络特定的NPDB进行检查。
3) The internal NPDB returns the routing number associated with the dialed directory number.
3) 内部NPDB返回与所拨目录号关联的路由号码。
4) The donor network uses the routing number to route the call to the new serving network.
4) 施主网络使用路由号码将呼叫路由到新的服务网络。
+-------------+ +-----------+ Number +-----------+
| Centralized | | New Serv. | porting | Old Serv. |
| NPDB | | Network |<------------| Network |
+-------------+ +-----------+ +-----------+
/\
|
4.|
|
+----------+ +----------+ 3. +----------+
| Orig. | | Donor |<----------| Internal |
| Network |--------------->| Network |---------->| NPDB |
+----------+ 1. +----------+ 2. +----------+
+-------------+ +-----------+ Number +-----------+
| Centralized | | New Serv. | porting | Old Serv. |
| NPDB | | Network |<------------| Network |
+-------------+ +-----------+ +-----------+
/\
|
4.|
|
+----------+ +----------+ 3. +----------+
| Orig. | | Donor |<----------| Internal |
| Network |--------------->| Network |---------->| NPDB |
+----------+ 1. +----------+ 2. +----------+
Figure 4 - Onward Routing (OR) Scheme.
图4-正向路由（OR）方案。
Only the ACQ scheme does not involve the donor network when routing the call to the new serving network of the dialed ported number. The other three schemes involve call setup to or signaling with the donor network.
只有ACQ方案在将呼叫路由到所拨端口号码的新服务网络时不涉及施主网络。其他三种方案涉及呼叫设置或与施主网络的信令。
Only the OR scheme requires the setup of two physical call segments, one from the Originating Network to the donor network and the other from the donor network to the new serving network. The OR scheme is the least efficient in terms of using the network transmission facilities. The QoR and Dropback schemes set up calls to the donor network first but release the call back to the Originating Network that then initiates a new call to the Current Serving Network. For the QoR and Dropback schemes, circuits are still reserved one by one
只有OR方案需要设置两个物理呼叫段，一个从发起网络到施主网络，另一个从施主网络到新的服务网络。OR方案在使用网络传输设施方面效率最低。QoR和Dropback方案首先设置对施主网络的呼叫，但释放对发起网络的呼叫，然后发起对当前服务网络的新呼叫。对于QoR和Dropback方案，仍然逐个保留电路
between the Originating Network and the donor network when the Originating Network sets up the call towards the donor network. Those circuits are released one by one when the call is released from the donor network back to the Originating Network. The ACQ scheme is the most efficient in terms of using the switching and transmission facilities for the call.
当发起网络建立对施主网络的呼叫时，在发起网络和施主网络之间。当呼叫从施主网络释放回发起网络时，这些电路将逐个释放。ACQ方案在使用呼叫的交换和传输设施方面是最有效的。
Both the ACQ and QoR schemes involve Centralized NPDBs for the Originating Network to retrieve the routing information. Centralized NPDB means that the NPDB contains ported number information from multiple networks. This is in contrast to the internal network-specific NPDB that is used for the Dropback and OR schemes. The internal NPDB only contains information about the numbers that were ported out of the donor network. The internal NPDB can be a stand-alone database that contains information about all or some ported-out numbers from the donor network. It can also reside on the donor switch and only contain information about those numbers ported out of the donor switch. In that case, no query to a stand-alone internal NPDB is required. The donor switch for a particular phone number is the switch to which the number range is assigned from which that phone number was originally assigned.
ACQ和QoR方案都涉及发起网络的集中式NPDB来检索路由信息。集中式NPDB意味着NPDB包含来自多个网络的端口号信息。这与用于回退和/或方案的内部网络特定NPDB形成对比。内部NPDB只包含有关从施主网络移植的号码的信息。内部NPDB可以是一个独立的数据库，其中包含来自施主网络的所有或部分端口号的信息。它还可以驻留在施主交换机上，并且只包含有关从施主交换机移植的那些号码的信息。在这种情况下，不需要查询独立的内部NPDB。特定电话号码的施主开关是指将号码范围分配到的开关，该电话号码最初是从该开关分配的。
For example, number ranges in the North American Numbering Plan (NANP) are usually assigned in the form of central office codes (CO codes) comprising a six-digit prefix formatted as a NPA+NXX. Thus a switch serving +1-202-533 would typically serve +1-202-533-0000 through +1-202-533-9999. In major cities, switches usually host several CO codes. NPA stands for Numbering Plan Area, which is also known as the area code. It is three-digits long and has the format of NXX where N is any digit from 2 to 9 and X is any digit from 0 to 9. NXX, in the NPA+NXX format, is known as the office code that has the same format as the NPA. When a NPA+NXX code is set as "portable" in the Local Exchange Routing Guide (LERG), it becomes a "portable NPA+NXX" code.
例如，北美编号计划（NANP）中的编号范围通常以中央办公室代码（CO代码）的形式分配，包括格式为NPA+NXX的六位前缀。因此，服务于+1-202-533的交换机通常服务于+1-202-533-0000到+1-202-533-9999。在大城市，交换机通常具有多个CO代码。NPA代表编号计划区域，也称为区号。它有三位数长，格式为NXX，其中N是2到9之间的任意数字，X是0到9之间的任意数字。NXX采用NPA+NXX格式，称为与NPA格式相同的办公室代码。当NPA+NXX代码在本地Exchange路由指南（LERG）中设置为“可移植”时，它将成为“可移植NPA+NXX”代码。
Similarly, in other national E.164 numbering plans, number ranges cover a contiguous range of numbers within that range. Once a number within that range has ported away from the donor network, all numbers in that range are considered potentially ported and should be queried in the NPDB.
同样，在其他国家E.164编号计划中，编号范围涵盖该范围内的连续编号范围。一旦该范围内的一个数字从施主网络转移出去，该范围内的所有数字都被视为可能被转移，应该在NPDB中查询。
The ACQ scheme has two versions. One version is for the Originating Network to always query the NPDB when a call is received from the caller regardless of whether the dialed directory number belongs to any number range that is portable or has at least one number ported out. The other version is to check whether the dialed directory number belongs to any number range that is portable or has at least one number ported out. If yes, an NPDB query is sent. If not, no
ACQ方案有两个版本。一种版本是，当从呼叫者接收到呼叫时，始发网络始终查询NPDB，而不管所拨打的目录号是否属于任何可移植的号码范围，或者至少有一个号码已移植出去。另一个版本是检查拨出的目录号是否属于任何可移植的号码范围，或者至少有一个号码已移植出去。如果是，则发送NPDB查询。如果没有，则没有
NPDB query is sent. The former performs better when there are many portable number ranges. The latter performs better when there are not too many portable number ranges at the expense of checking every call to see whether NPDB query is needed. The latter ACQ scheme is similar to the QoR scheme, except that the QoR scheme uses call setup and relies on the donor network to indicate "number ported out" before launching the NPDB query.
发送NPDB查询。当存在多个可移植数字范围时，前者的性能更好。当没有太多的可移植号码范围时，后者的性能更好，代价是检查每个调用以查看是否需要NPDB查询。后一种ACQ方案与QoR方案类似，不同之处在于QoR方案使用呼叫设置，并且在启动NPDB查询之前依赖于施主网络指示“已端口输出的号码”。
As indicated earlier, the ACQ and QoR schemes require that a switch query the NPDB for routing information. Various standards have been defined for the switch-to-NPDB interface. Those interfaces with their protocol stacks are briefly described below. The term "NPDB" is used for a stand-alone database that may support just one or some or all of the interfaces mentioned below. The NPDB query contains the dialed directory number and the NPDB response contains the routing number. There is certainly other information that is sent in the query and response. The primary interest is to get the routing number from the NPDB to the switch for call routing.
如前所述，ACQ和QoR方案要求交换机向NPDB查询路由信息。已为切换到NPDB接口定义了各种标准。下面简要介绍这些接口及其协议栈。术语“NPDB”用于一个独立数据库，该数据库可能只支持下面提到的一个或部分或所有接口。NPDB查询包含已拨的目录号，NPDB响应包含路由号。在查询和响应中肯定会发送其他信息。主要的兴趣是获取从NPDB到交换机的路由号码以进行呼叫路由。
One of the following five NPDB interfaces can be used to query an NPDB:
以下五个NPDB接口之一可用于查询NPDB：
a) Advanced Intelligent Network (AIN) using the American National Standards Institute (ANSI) version of the Intelligent Network Application Part (INAP) [ANSI SS] [ANSI DB]. The INAP is carried on top of the protocol stack that includes the (ANSI) Message Transfer Part (MTP) Levels 1 through 3, ANSI SCCP and ANSI TCAP. This interface can be used by the wireline or wireless switches, is specific to the NP implementation in North America, and is modeled on the Public Office Dialing Plan (PODP) trigger defined in the Advanced Intelligent Network (AIN) 0.1 call model.
a) 高级智能网络（AIN）使用美国国家标准协会（ANSI）版本的智能网络应用部分（INAP）[ANSI SS][ANSI DB]。INAP位于协议栈顶部，协议栈包括（ANSI）消息传输部分（MTP）级别1至3、ANSI SCCP和ANSI TCAP。此接口可由有线或无线交换机使用，特定于北美的NP实施，并根据高级智能网络（AIN）0.1呼叫模型中定义的公共办公室拨号计划（PODP）触发器建模。
b) Intelligent Network (IN), which is similar to the one used for querying the 800 databases. The IN protocol is carried on top of the protocol stack that includes the ANSI MTP Levels 1 through 3, ANSI SCCP, and ANSI TCAP. This interface can be used by the wireline or wireless switches.
b) 智能网络（IN），类似于用于查询800个数据库的网络。IN协议位于协议栈顶部，协议栈包括ANSI MTP级别1到3、ANSI SCCP和ANSI TCAP。此接口可由有线或无线交换机使用。
c) ANSI IS-41 [IS41] [ISNP], which is carried on top of the protocol stack that includes the ANSI MTP Levels 1 through 3, ANSI SCCP, and ANSI TCAP. This interface can be used by the IS-41 based cellular/Personal Communication Services (PCS) wireless switches (e.g., AMPS, TDMA and CDMA). Cellular systems use spectrum at 800 MHz range and PCS systems use spectrum at 1900 MHz range.
c) ANSI IS-41[IS41][ISNP]，它位于协议栈顶部，包括ANSI MTP级别1到3、ANSI SCCP和ANSI TCAP。该接口可由基于IS-41的蜂窝/个人通信服务（PCS）无线交换机（如AMPS、TDMA和CDMA）使用。蜂窝系统在800 MHz范围内使用频谱，而PCS系统在1900 MHz范围内使用频谱。
d) Global System for Mobile Communication Mobile Application Part (GSM MAP) [GSM], which is carried on top of the protocol stack that includes the ANSI MTP Levels 1 through 3, ANSI SCCP, and International Telecommunication Union - Telecommunication Sector (ITU-TS) TCAP. It can be used by the PCS1900 wireless switches that are based on the GSM technologies. GSM is a series of wireless standards defined by the European Telecommunications Standards Institute (ETSI).
d) 全球移动通信系统移动应用部分（GSM MAP）[GSM]，它位于协议栈顶部，协议栈包括ANSI MTP级别1至3、ANSI SCCP和国际电信联盟-电信部门（ITU-TS）TCAP。它可用于基于GSM技术的PCS1900无线交换机。GSM是由欧洲电信标准协会（ETSI）定义的一系列无线标准。
e) ISUP triggerless translation. NP translations are performed transparently to the switching network by the signaling network (e.g., Signaling Transfer Points (STPs) or signaling gateways). ISUP IAM messages are examined to determine if the CdPN field has already been translated, and if not, an NPDB query is performed, and the appropriate parameters in the IAM message modified to reflect the results of the translation. The modified IAM message is forwarded by the signaling node on to the designated DPC in a transparent manner to continue call setup. The NPDB can be integrated with the signaling node or, accessed via an Application Programming Interface (API) locally, or by a query to a remote NPDB using a proprietary protocol or the schemes described above.
e) ISUP无触发翻译。NP转换通过信令网络（例如，信令传输点（STP）或信令网关）对交换网络透明地执行。检查ISUP IAM消息以确定CdPN字段是否已翻译，如果未翻译，则执行NPDB查询，并修改IAM消息中的适当参数以反映翻译结果。修改后的IAM消息由信令节点以透明方式转发到指定的DPC，以继续呼叫设置。NPDB可与信令节点集成，或通过本地应用程序编程接口（API）访问，或通过使用专有协议或上述方案查询远程NPDB。
Wireline switches have the choice of using either (a), (b), or (e). IS-41 based wireless switches have the choice of using (a), (b), (c), or (e). PCS1900 wireless switches have the choice of using (a), (b), (d), or (e). In the United States, service provider portability will be supported by both the wireline and wireless systems, not only within the wireline or wireless domain but also across the wireline/wireless boundary. However, this is not true in Europe where service provider portability is usually supported only within the wireline or wireless domain, not across the wireline/wireless boundary due to explicit use of service-specific number range prefixes. The reason is to avoid caller confusion about the call charge. GSM systems in Europe are assigned distinctive destination network codes, and the caller pays a higher charge when calling a GSM directory number.
有线开关可选择使用（a）、（b）或（e）项。基于IS-41的无线交换机可以选择使用（a）、（b）、（c）或（e）。PCS1900无线交换机可以选择使用（a）、（b）、（d）或（e）。在美国，有线和无线系统都将支持服务提供商的可移植性，不仅在有线或无线域内，而且跨有线/无线边界。然而，在欧洲，情况并非如此，因为服务提供商的可移植性通常仅在有线或无线域内得到支持，而不跨越有线/无线边界，因为明确使用了特定于服务的数字范围前缀。原因是为了避免来电者对通话费用产生混淆。欧洲的GSM系统被分配了独特的目的地网络代码，呼叫方在拨打GSM目录号码时支付更高的费用。
One of the following two interfaces can be used to query an NPDB:
以下两个接口之一可用于查询NPDB：
a) Capability Set 1 (CS1) of the ITU-TS INAP [CS1], which is carried on top of the protocol stack that includes the ITU-TS MTP Levels 1 through 3, ITU-TS SCCP, and ITU-TS TCAP.
a) ITU-TS INAP[CS1]的能力集1（CS1），它位于协议栈顶部，包括ITU-TS MTP级别1至3、ITU-TS SCCP和ITU-TS TCAP。
b) Capability Set 2 (CS2) of the ITU-TS INAP [CS2], which is carried on top of the protocol stack that includes the ITU-TS MTP Levels 1 through 3, ITU-TS SCCP, and ITU-TS TCAP.
b) ITU-TS INAP[CS2]的能力集2（CS2），它位于协议栈的顶部，包括ITU-TS MTP级别1到3、ITU-TS SCCP和ITU-TS TCAP。
Wireline switches have the choice of using either (a) or (b); however, all the implementations in Europe so far are based on CS1. As indicated earlier that number portability in Europe does not go across the wireline/wireless boundary. The wireless switches can also use (a) or (b) to query the NPDBs if those NPDBs contains ported wireless directory numbers. The term "Mobile Number Portability (MNP)" is used for the support of service provider portability by the GSM networks in Europe.
有线开关可选择使用（a）或（b）；然而，到目前为止，欧洲的所有实现都基于CS1。如前所述，欧洲的号码可携性并不跨越有线/无线边界。无线交换机还可以使用（a）或（b）查询NPDB是否包含移植的无线目录号。术语“移动号码便携性（MNP）”用于支持欧洲GSM网络的服务提供商便携性。
In most, if not all, cases in Europe, the calls to the wireless directory numbers are routed to the wireless donor network first. Over there, an internal NPDB is queried to determine whether the dialed wireless directory number has been ported out or not. In this case, the interface to the internal NPDB is not subject to standardization.
在欧洲的大多数情况下（如果不是全部的话），对无线目录号码的呼叫首先被路由到无线捐赠网络。在那里，一个内部NPDB被查询以确定所拨的无线目录号是否已被移植出去。在这种情况下，与内部NPDB的接口不需要标准化。
MNP in Europe can also be supported via the MNP Signaling Relay Function (MNP-SRF). Again, an internal NPDB or a database integrated at the MNP-SRF is used to modify the SCCP Called Party Address parameter in the GSM MAP messages so that they can be re-directed to the wireless serving network. Call routing involving MNP will be explained in Section 6.2.
也可以通过MNP信令中继功能（MNP-SRF）支持欧洲的MNP。同样，在MNP-SRF处集成的内部NPDB或数据库用于修改GSM映射消息中的SCCP被叫方地址参数，以便它们可以被重新定向到无线服务网络。涉及MNP的呼叫路由将在第6.2节中解释。
This section discusses the call routing after the routing information has been retrieved either through an NPDB query or an internal database lookup at the donor switch, or from the Integrated Services Digital Network User Part (ISUP) signaling message (e.g., for the Dropback scheme). For the ACQ, QoR and Dropback schemes, it is the Originating Network that has the routing information and is ready to route the call. For the OR scheme, it is the donor network that has the routing information and is ready to route the call.
本节讨论通过NPDB查询或施主交换机上的内部数据库查找，或从综合业务数字网络用户部分（ISUP）信令消息（例如，对于回退方案）检索路由信息后的呼叫路由。对于ACQ、QoR和Dropback方案，具有路由信息并准备好路由呼叫的发起网络。对于OR方案，具有路由信息并准备好路由呼叫的施主网络。
A number of triggering schemes may be employed that determine where in the call path the NPDB query is performed. In the U.S. a "N-1" policy is used, which essentially says that for local calls, the originating local carriers performs the query. Otherwise, the long distance carrier is expected to follow through with the query. To ensure independence of the actual trigger policy employed in any one carrier, forward call signaling is used to flag that an NPDB query has already been performed and to therefore suppress any subsequent NP triggers that may be encountered in downstream switches, in downstream networks. This allows the earliest able network in the call path to perform the query without introducing additional costs and call setup delays when redundant queries are performed downstream.
可以采用许多触发方案来确定在呼叫路径中执行NPDB查询的位置。在美国，使用了“N-1”策略，这基本上是说，对于本地呼叫，发起本地运营商执行查询。否则，长途运营商将完成查询。为了确保在任何一个载波中使用的实际触发策略的独立性，前向呼叫信令用于标记已经执行了NPDB查询，并因此抑制在下游网络中的下游交换机中可能遇到的任何后续NP触发。这使得在下游执行冗余查询时，呼叫路径中最早的可恢复网络能够执行查询，而不会引入额外成本和呼叫设置延迟。
In the U.S. and Canada, a ten-digit North American Numbering Plan (NANP) number called Location Routing Number (LRN) is assigned to every switch involved in NP. In the NANP, a switch is not reachable unless it has a unique number range (CO code) assigned to it. Consequently, the LRN for a switch is always assigned out of a CO code that is assigned to that switch.
在美国和加拿大，为NP中涉及的每个交换机分配一个称为位置路由号码（LRN）的十位北美编号计划（NANP）号码。在NANP中，除非为交换机分配了唯一的号码范围（CO代码），否则无法访问交换机。因此，交换机的LRN总是从分配给该交换机的CO代码中分配。
The LRN assigned to a switch currently serving a particular ported telephone number is returned as the network routing address in the NPDB response. The service portability scheme that was adopted in the North America is very often referred to as the LRN scheme or method.
分配给当前服务于特定端口电话号码的交换机的LRN在NPDB响应中作为网络路由地址返回。北美采用的服务可移植性方案通常被称为LRN方案或方法。
LRN serves as a network address for terminating calls served off that switch using ported numbers. The LRN is assigned by the switch operator using any of the unique CO codes (NPA+NXX) assigned to that switch. The LRN is considered a non-dialable address, as the same 10-digit number value may be assigned to a line on that switch. A switch may have more than one LRN.
LRN作为一个网络地址，用于使用端口号终止由该交换机提供的呼叫。LRN由交换机操作员使用分配给该交换机的任何唯一CO代码（NPA+NXX）分配。LRN被视为不可拨号地址，因为相同的10位数字值可能被分配给该交换机上的线路。一个交换机可能有多个LRN。
During call routing/processing, a switch performs an NPDB query to obtain the LRN associated with the dialed directory number. NPDB queries are performed for all the dialed directory numbers whose NPA+NXX codes are marked as portable NPA+NXX at that switch. When formulating the ISUP Initial Address Message (IAM) to be sent to the next switch, the switch puts the ten-digit LRN in the ISUP Called Party Number (CdPN) parameter and the originally dialed directory number in the ISUP Generic Address parameter (GAP). A new code in the GAP was defined to indicate that the address information in the GAP is the dialed directory number. A new bit in the ISUP Forward Call Indicator (FCI) parameter, the Ported Number Translation Indicator (PNTI) bit, is set to imply that NPDB query has already been performed. All the switches in the downstream will not perform the NPDB query if the PNTI bit is set.
在呼叫路由/处理过程中，交换机执行NPDB查询以获取与所拨目录号关联的LRN。对其NPA+NXX代码在该交换机上标记为portable NPA+NXX的所有已拨目录号执行NPDB查询。当制定要发送到下一个交换机的ISUP初始地址消息（IAM）时，交换机将十位LRN放入ISUP被叫方号码（CdPN）参数中，并将最初拨打的目录号放入ISUP通用地址参数（GAP）。在GAP中定义了一个新代码，以指示GAP中的地址信息是所拨打的目录号。ISUP前向呼叫指示符（FCI）参数中的一个新位，即端口号码转换指示符（PNTI）位，被设置为表示已经执行了NPDB查询。如果设置了PNTI位，则下游的所有交换机将不会执行NPDB查询。
When the terminating switch receives the IAM and sees the PNTI bit in the FCI parameter set and its own LRN in the CdPN parameter, it retrieves the originally dialed directory number from the GAP and uses the dialed directory number to terminate the call.
当终端交换机接收到IAM并在FCI参数集中看到PNTI位，在CdPN参数中看到它自己的LRN时，它从GAP中检索最初拨打的目录号，并使用拨打的目录号终止呼叫。
A dialed directory number with a portable NPA+NXX does not imply that a directory number has been ported. The NPDBs currently do not store records for non-ported directory numbers. In that case, the NPDB will return the same dialed directory number instead of the LRN. The switch will then set the PNTI bit, but keep the dialed directory number in the CdPN parameter.
使用便携式NPA+NXX拨打的目录号并不意味着已移植目录号。NPDB当前不存储非移植目录号的记录。在这种情况下，NPDB将返回相同的拨号目录号，而不是LRN。然后，交换机将设置PNTI位，但将拨号目录号保留在CdPN参数中。
In the real world environment, the Originating Network is not always the one that performs the NPDB query. For example, it is usually the long distance carriers that query the NPDBs for long distance calls. In that case, the Originating Network operated by the local exchange carrier (LEC) simply routes the call to the long distance carrier that is to handle that call. A wireless network acting as the Originating Network can also route the call to the interconnected local exchange carrier network if it does not want to support the NPDB interface at its mobile switches.
在现实环境中，发起网络并不总是执行NPDB查询的网络。例如，通常是长途运营商向NPDB查询长途呼叫。在这种情况下，由本地交换运营商（LEC）操作的发起网络只是将呼叫路由到要处理该呼叫的长途运营商。如果无线网络不想在其移动交换机上支持NPDB接口，则作为始发网络的无线网络也可以将呼叫路由到互连的本地交换载波网络。
In some European countries, a routing number is prefixed to the dialed directory number. The ISUP CdPN parameter in the IAM will contain the routing prefix and the dialed directory number. For example, United Kingdom uses routing prefixes with the format of 5XXXXX and Italy uses C600XXXXX as the routing prefix. The networks use the information in the ISUP CdPN parameter to route the call to the New/Current Serving Network.
在一些欧洲国家，在拨出的目录号码前加上一个路由号码。IAM中的ISUP CdPN参数将包含路由前缀和拨号目录号。例如，英国使用5XXXXX格式的路由前缀，意大利使用C600XXXXX作为路由前缀。网络使用ISUP CdPN参数中的信息将呼叫路由到新的/当前的服务网络。
The routing prefix can identify the Current Serving Network or the Current Serving Switch of a ported number. For the former case, another query to the "internal" NPDB at the Current Serving Network is required to identify the Current Serving Switch before routing the call to that switch. This shields the Current Serving Switch information for a ported number from the other networks at the expense of an additional NPDB query. Another routing number, that be meaningful within the Current Serving Network, will replace the previously prefixed routing number in the ISUP CdPN parameter. For the latter case, the call is routed to the Current Serving Switch without an additional NPDB query.
路由前缀可以识别端口号的当前服务网络或当前服务交换机。对于前一种情况，在将呼叫路由到该交换机之前，需要对当前服务网络上的“内部”NPDB进行另一次查询，以识别当前服务交换机。这将屏蔽来自其他网络的端口号的当前服务交换机信息，但需要额外的NPDB查询。另一个在当前服务网络中有意义的路由号码将替换ISUP CdPN参数中先前前缀的路由号码。对于后一种情况，呼叫被路由到当前服务交换机，而不需要额外的NPDB查询。
When the terminating switch receives the IAM and sees its own routing prefix in the CdPN parameter, it retrieves the originally dialed directory number after the routing prefix, and uses the dialed directory number to terminate the call.
当终端交换机收到IAM并在CdPN参数中看到自己的路由前缀时，它会在路由前缀之后检索最初拨打的目录号，并使用拨打的目录号终止呼叫。
The call routing example described above shows one of the three methods that can be used to transport the Directory Number (DN) and the Routing Number (RN) in the ISUP IAM message. In addition, some other information may be added/modified as is listed in the ETSI 302 097 document [ETSIISUP], which is based on the ITU-T Recommendation Q.769.1 [ITUISUP]. The three methods and the enhancements in ISUP to support number portability are briefly described below:
上述呼叫路由示例显示了可用于传输ISUP IAM消息中的目录号（DN）和路由号（RN）的三种方法之一。此外，可以添加/修改ETSI 302 097文件[ETSIISUP]中列出的一些其他信息，该文件基于ITU-T建议Q.769.1[ITUISUP]。下面简要介绍ISUP中支持号码可移植性的三种方法和增强功能：
a) Two separate parameters with the CdPN parameter containing the RN and a new Called Directory Number (CdDN) parameter containing the DN. A new value for the Nature of Address (NOA) indicator in the
a) 两个单独的参数，其中CdPN参数包含RN，新的Called Directory Number（CdDN）参数包含DN。中地址性质（NOA）指示符的新值
CdPN parameter is defined to indicate that the RN is in the CdPN parameter. The switches use the CdPN parameter to route the call as is done today.
CdPN参数的定义表明RN在CdPN参数中。交换机使用CdPN参数来路由呼叫，就像今天一样。
b) Two separate parameters with the CdPN parameter containing the DN and a new Network Routing Number (NRN) parameter containing the RN. This method requires that the switches use the NRN parameter to route the call.
b) 两个单独的参数，其中CdPN参数包含DN，新的网络路由号码（NRN）参数包含RN。此方法要求交换机使用NRN参数来路由呼叫。
c) Concatenated parameter with the CdPN parameter containing the RN plus the DN. A new Nature of Address (NOA) indicator in the CdPN parameter is defined to indicate that the RN is concatenated with the DN in the CdPN parameter. Some countries may not use new NOA value because the routing prefix does not overlap with the dialed directory numbers. But if the routing prefix overlaps with the dialed directory numbers, a new NOA value must be assigned. For example, Spain uses "XXXXXX" as the routing prefix to identify the new serving network and uses a new NOA value of 126.
c) 将参数与包含RN和DN的CdPN参数连接起来。在CdPN参数中定义了地址（NOA）指示符的新性质，以指示RN与CdPN参数中的DN连接。某些国家/地区可能不使用新的NOA值，因为路由前缀与所拨打的目录号不重叠。但如果路由前缀与已拨的目录号重叠，则必须分配新的NOA值。例如，西班牙使用“XXXXXX”作为路由前缀来标识新的服务网络，并使用新的NOA值126。
There is also a network option to add a new ISUP parameter called Number Portability Forwarding Information parameter. This parameter has a four-bit Number Portability Status Indicator field that can provide an indication whether number portability query is done for the called directory number and whether the called directory number is ported or not if the number portability query is done.
还有一个网络选项可以添加一个新的ISUP参数，称为号码可移植性转发信息参数。此参数有一个四位数字可移植性状态指示符字段，该字段可以指示是否对被叫目录号进行了数字可移植性查询，以及如果完成了数字可移植性查询，是否对被叫目录号进行了移植。
Please note that all of the NP enhancements for a ported number can only be used in the country that defined them. This is because number portability is supported within a nation. Within each nation, the telecommunications industry or the regulatory bodies can decide which method or methods to use. Number portability related parameters and coding are usually not passed across the national boundaries unless the interconnection agreements allow it. For example, a UK routing prefix can only be used in the UK, and would cause a routing problem if it appears outside the UK.
请注意，端口号的所有NP增强功能只能在定义它们的国家/地区使用。这是因为在一个国家内支持号码可移植性。在每个国家，电信行业或监管机构可以决定使用哪种方法。除非互联协议允许，否则与号码可携性相关的参数和编码通常不会跨越国界。例如，英国路由前缀只能在英国使用，如果它出现在英国境外，则会导致路由问题。
As indicated earlier, an originating wireless network can query the NPDB and concatenate the RN with DN in the CdPN parameter and route the call directly to the Current Serving Network.
如前所述，发起无线网络可以查询NPDB并在CdPN参数中将RN与DN连接起来，并将呼叫直接路由到当前服务网络。
If NPDBs do not contain information about the wireless directory numbers, the call, originated from either a wireline or a wireless network, will be routed to the Wireless donor network. Over there, an internal NPDB is queried to retrieve the RN that then is concatenated with the DN in the CdPN parameter.
如果NPDB不包含有关无线目录号的信息，则来自有线或无线网络的呼叫将被路由到无线施主网络。在那里，查询一个内部NPDB以检索RN，然后该RN与CdPN参数中的DN连接。
There are several ways of realizing MNP. If MNP-SRF is supported, the Gateway Mobile Services Switching Center (GMSC) at the wireless
有几种实现MNP的方法。如果支持MNP-SRF，则网关移动服务交换中心（GMSC）在无线
donor network can send the GSM MAP Send Routing Information (SRI) message to the MNP-SRF when receiving a call from the wireline network. The MNP-SRF interrogates an internal or integrated NPDB for the RN of the MNP-SRF of the wireless Current Serving Network and prefixes the RN to the dialed wireless directory number in the global title address information in the SCCP Called Party Address (CdPA) parameter. This SRI message will be routed to the MNP-SRF of the wireless Current Serving Network, which then responds with an acknowledgement by providing the RN plus the dialed wireless directory number as the Mobile Station Roaming Number (MSRN). The GMSC of the wireless donor network formulates the ISUP IAM with the RN plus the dialed wireless directory number in the CdPN parameter and routes the call to the wireless Current Serving Network. A GMSC of the wireless Current Serving Network receives the call and sends an SRI message to the associated MNP-SRF where the global title address information of the SCCP CdPA parameter contains only the dialed wireless directory number. The MNP-SRF then replaces the global title address information in the SCCP CdPA parameter with the address information associated with a Home Location Register (HLR) that hosts the dialed wireless directory number and forwards the message to that HLR after verifying that the dialed wireless directory number is a ported-in number. The HLR then returns an acknowledgement by providing an MSRN for the GMSC to route the call to the MSC that currently serves the mobile station that is associated with the dialed wireless directory number. Please see [MNP] for details and additional scenarios.
当从有线网络接收呼叫时，施主网络可以向MNP-SRF发送GSM MAP发送路由信息（SRI）消息。MNP-SRF为无线当前服务网络的MNP-SRF的RN询问内部或集成的NPDB，并在SCCP被叫方地址（CdPA）参数中的全局标题地址信息中将RN作为拨号无线目录号的前缀。该SRI消息将被路由到无线当前服务网络的MNP-SRF，然后该MNP-SRF通过提供RN加上已拨无线目录号作为移动站漫游号码（MSRN）来响应确认。无线施主网络的GMSC使用RN加上CdPN参数中的已拨无线目录号来制定ISUP IAM，并将呼叫路由到无线当前服务网络。无线当前服务网络的GMSC接收呼叫并向相关联的MNP-SRF发送SRI消息，其中SCCP CdPA参数的全局标题地址信息仅包含所拨打的无线目录号。然后，MNP-SRF将SCCP CdPA参数中的全局标题地址信息替换为与承载拨号无线目录号的归属位置寄存器（HLR）相关联的地址信息，并在验证拨号无线目录号是否为端口号后将消息转发给该HLR。HLR然后通过为GMSC提供MSRN来返回确认，以将呼叫路由到当前服务于与所拨无线目录号相关联的移动站的MSC。有关详细信息和其他场景，请参见[MNP]。
This section shows the known SPNP implementations worldwide.
本节展示了世界范围内已知的SPNP实现。
+-------------+----------------------------------------------------+
+ Country + SPNP Implementation +
+-------------+----------------------------------------------------+
+ Argentina + Analyzing operative viability now. Will determine +
+ + whether portability should be made obligatory +
+ + after a technical solution has been determined. +
+-------------+----------------------------------------------------+
+ Australia + NP supported by wireline operators since 11/30/99. +
+ + NP among wireless operators in March/April 2000, +
+ + but may be delayed to 1Q01. The access provider +
+ + or long distance provider has the obligation to +
+ + route the call to the correct destination. The +
+ + donor network is obligated to maintain and make +
+ + available a register of numbers ported away from +
+ + its network. Telstra uses onward routing via an +
+ + on-switch solution. +
+-------------+----------------------------------------------------+
+-------------+----------------------------------------------------+
+ Country + SPNP Implementation +
+-------------+----------------------------------------------------+
+ Argentina + Analyzing operative viability now. Will determine +
+ + whether portability should be made obligatory +
+ + after a technical solution has been determined. +
+-------------+----------------------------------------------------+
+ Australia + NP supported by wireline operators since 11/30/99. +
+ + NP among wireless operators in March/April 2000, +
+ + but may be delayed to 1Q01. The access provider +
+ + or long distance provider has the obligation to +
+ + route the call to the correct destination. The +
+ + donor network is obligated to maintain and make +
+ + available a register of numbers ported away from +
+ + its network. Telstra uses onward routing via an +
+ + on-switch solution. +
+-------------+----------------------------------------------------+
+-------------+----------------------------------------------------+
+ Country + SPNP Implementation +
+-------------+----------------------------------------------------+
+ Austria + Uses onward routing at the donor network. Routing +
+ + prefix is "86xx" where "xx" identifies the +
+ + recipient network. +
+-------------+----------------------------------------------------+
+ Belgium + ACQ selected by the industry. Routing prefix is +
+ + "Cxxxx" where "xxxx" identifies the recipient +
+ + switch. Another routing prefix is "C00xx" with "xx"+
+ + identifying the recipient network. Plan to use NOA+
+ + to identify concatenated numbers and abandon the +
+ + hexadecimal routing prefix. +
+-------------+----------------------------------------------------+
+ Brazil + Considering NP for wireless users. +
+-------------+----------------------------------------------------+
+ Chile + There has been discussions lately on NP. +
+-------------+----------------------------------------------------+
+ Colombia + There was an Article 3.1 on NP to support NP prior +
+ + to December 31, 1999 when NP became technically +
+ + possible. Regulator has not yet issued regulations +
+ + concerning this matter. +
+-------------+----------------------------------------------------+
+ Denmark + Uses ACQ. Routing number not passed between +
+ + operators; however, NOA is set to "112" to +
+ + indicate "ported number." QoR can be used based +
+ + on bilateral agreements. +
+-------------+----------------------------------------------------+
+ Finland + Uses ACQ. Routing prefix is "1Dxxy" where "xxy" +
+ + identifies the recipient network and service type. +
+-------------+----------------------------------------------------+
+ France + Uses onward routing. Routing prefix is "Z0xxx" +
+ + where "xxx" identifies the recipient switch. +
+-------------+----------------------------------------------------+
+ Germany + The originating network needs to do necessary +
+ + rerouting. Operators decide their own solution(s).+
+ + Deutsche Telekom uses ACQ. Routing prefix is +
+ + "Dxxx" where "xxx" identifies the recipient +
+ + network. +
+-------------+----------------------------------------------------+
+ Hong Kong + Recipient network informs other networks about +
+ + ported-in numbers. Routing prefix is "14x" where +
+ + "14x" identifies the recipient network, or a +
+ + routing number of "4x" plus 7 or 8 digits is used +
+ + where "4x" identifies the recipient network and +
+ + the rest of digits identify the called party. +
+-------------+----------------------------------------------------+
+-------------+----------------------------------------------------+
+ Country + SPNP Implementation +
+-------------+----------------------------------------------------+
+ Austria + Uses onward routing at the donor network. Routing +
+ + prefix is "86xx" where "xx" identifies the +
+ + recipient network. +
+-------------+----------------------------------------------------+
+ Belgium + ACQ selected by the industry. Routing prefix is +
+ + "Cxxxx" where "xxxx" identifies the recipient +
+ + switch. Another routing prefix is "C00xx" with "xx"+
+ + identifying the recipient network. Plan to use NOA+
+ + to identify concatenated numbers and abandon the +
+ + hexadecimal routing prefix. +
+-------------+----------------------------------------------------+
+ Brazil + Considering NP for wireless users. +
+-------------+----------------------------------------------------+
+ Chile + There has been discussions lately on NP. +
+-------------+----------------------------------------------------+
+ Colombia + There was an Article 3.1 on NP to support NP prior +
+ + to December 31, 1999 when NP became technically +
+ + possible. Regulator has not yet issued regulations +
+ + concerning this matter. +
+-------------+----------------------------------------------------+
+ Denmark + Uses ACQ. Routing number not passed between +
+ + operators; however, NOA is set to "112" to +
+ + indicate "ported number." QoR can be used based +
+ + on bilateral agreements. +
+-------------+----------------------------------------------------+
+ Finland + Uses ACQ. Routing prefix is "1Dxxy" where "xxy" +
+ + identifies the recipient network and service type. +
+-------------+----------------------------------------------------+
+ France + Uses onward routing. Routing prefix is "Z0xxx" +
+ + where "xxx" identifies the recipient switch. +
+-------------+----------------------------------------------------+
+ Germany + The originating network needs to do necessary +
+ + rerouting. Operators decide their own solution(s).+
+ + Deutsche Telekom uses ACQ. Routing prefix is +
+ + "Dxxx" where "xxx" identifies the recipient +
+ + network. +
+-------------+----------------------------------------------------+
+ Hong Kong + Recipient network informs other networks about +
+ + ported-in numbers. Routing prefix is "14x" where +
+ + "14x" identifies the recipient network, or a +
+ + routing number of "4x" plus 7 or 8 digits is used +
+ + where "4x" identifies the recipient network and +
+ + the rest of digits identify the called party. +
+-------------+----------------------------------------------------+
+-------------+----------------------------------------------------+
+ Country + SPNP Implementation +
+-------------+----------------------------------------------------+
+ Ireland + Operators choose their own solution but use onward +
+ + routing now. Routing prefix is "1750" as the intra-+
+ + network routing code (network-specific) and +
+ + "1752xxx" to "1759xxx" for GNP where "xxx" +
+ + identifies the recipient switch. +
+-------------+----------------------------------------------------+
+ Italy + Uses onward routing. Routing prefix is "C600xxxxx" +
+ + where "xxxxx" identifies the recipient switch. +
+ + Telecom Italia uses IN solution and other operators+
+ + use on-switch solution. +
+-------------+----------------------------------------------------+
+ Japan + Uses onward routing. Donor switch uses IN to get +
+ + routing number. +
+-------------+----------------------------------------------------+
+ Mexico + NP is considered in the Telecom law; however, the +
+ + regulator (Cofetel) or the new local entrants have +
+ + started no initiatives on this process. +
+-------------+----------------------------------------------------+
+ Netherlands + Operators decide NP scheme to use. Operators have +
+ + chosen ACQ or QoR. KPN implemented IN solution +
+ + similar to U.S. solution. Routing prefix is not +
+ + passed between operators. +
+-------------+----------------------------------------------------+
+ Norway + OR for short-term and ACQ for long-term. QoR is +
+ + optional. Routing prefix can be "xxx" with NOA=8, +
+ + or "142xx" with NOA=3 where "xxx" or "xx" +
+ + identifies the recipient network. +
+------------ +----------------------------------------------------+
+ Peru + Wireline NP may be supported in 2001. +
+-------------+----------------------------------------------------+
+ Portugal + No NP today. +
+-------------+----------------------------------------------------+
+ Spain + Uses ACQ. Telefonica uses QoR within its network. +
+ + Routing prefix is "xxyyzz" where "xxyyzz" +
+ + identifies the recipient network. NOA is set to +
+ + 126. +
+-------------+----------------------------------------------------+
+ Sweden + Standardized the ACQ but OR for operators without +
+ + IN. Routing prefix is "xxx" with NOA=8 or "394xxx" +
+ + with NOA=3 where "xxx" identifies the recipient +
+ + network. But operators decide NP scheme to use. +
+ + Telia uses onward routing between operators. +
+-------------+----------------------------------------------------+
+-------------+----------------------------------------------------+
+ Country + SPNP Implementation +
+-------------+----------------------------------------------------+
+ Ireland + Operators choose their own solution but use onward +
+ + routing now. Routing prefix is "1750" as the intra-+
+ + network routing code (network-specific) and +
+ + "1752xxx" to "1759xxx" for GNP where "xxx" +
+ + identifies the recipient switch. +
+-------------+----------------------------------------------------+
+ Italy + Uses onward routing. Routing prefix is "C600xxxxx" +
+ + where "xxxxx" identifies the recipient switch. +
+ + Telecom Italia uses IN solution and other operators+
+ + use on-switch solution. +
+-------------+----------------------------------------------------+
+ Japan + Uses onward routing. Donor switch uses IN to get +
+ + routing number. +
+-------------+----------------------------------------------------+
+ Mexico + NP is considered in the Telecom law; however, the +
+ + regulator (Cofetel) or the new local entrants have +
+ + started no initiatives on this process. +
+-------------+----------------------------------------------------+
+ Netherlands + Operators decide NP scheme to use. Operators have +
+ + chosen ACQ or QoR. KPN implemented IN solution +
+ + similar to U.S. solution. Routing prefix is not +
+ + passed between operators. +
+-------------+----------------------------------------------------+
+ Norway + OR for short-term and ACQ for long-term. QoR is +
+ + optional. Routing prefix can be "xxx" with NOA=8, +
+ + or "142xx" with NOA=3 where "xxx" or "xx" +
+ + identifies the recipient network. +
+------------ +----------------------------------------------------+
+ Peru + Wireline NP may be supported in 2001. +
+-------------+----------------------------------------------------+
+ Portugal + No NP today. +
+-------------+----------------------------------------------------+
+ Spain + Uses ACQ. Telefonica uses QoR within its network. +
+ + Routing prefix is "xxyyzz" where "xxyyzz" +
+ + identifies the recipient network. NOA is set to +
+ + 126. +
+-------------+----------------------------------------------------+
+ Sweden + Standardized the ACQ but OR for operators without +
+ + IN. Routing prefix is "xxx" with NOA=8 or "394xxx" +
+ + with NOA=3 where "xxx" identifies the recipient +
+ + network. But operators decide NP scheme to use. +
+ + Telia uses onward routing between operators. +
+-------------+----------------------------------------------------+
+-------------+----------------------------------------------------+
+ Country + SPNP Implementation +
+-------------+----------------------------------------------------+
+ Switzerland + Uses OR now and QoR in 2001. Routing prefix is +
+ + "980xxx" where "xxx" identifies the recipient +
+ + network. +
+-------------+----------------------------------------------------+
+ UK + Uses onward routing. Routing prefix is "5xxxxx" +
+ + where "xxxxx" identifies the recipient switch. NOA +
+ + is 126. BT uses the dropback scheme in some parts +
+ + of its network. +
+-------------+----------------------------------------------------+
+ US + Uses ACQ. "Location Routing Number (LRN)" is used +
+ + in the Called Party Number parameter. Called party+
+ + number is carried in the Generic Address Parameter +
+ + Use a PNTI indicator in the Forward Call Indicator +
+ + parameter to indicate that NPDB dip has been +
+ + performed. +
+-------------+----------------------------------------------------+
+-------------+----------------------------------------------------+
+ Country + SPNP Implementation +
+-------------+----------------------------------------------------+
+ Switzerland + Uses OR now and QoR in 2001. Routing prefix is +
+ + "980xxx" where "xxx" identifies the recipient +
+ + network. +
+-------------+----------------------------------------------------+
+ UK + Uses onward routing. Routing prefix is "5xxxxx" +
+ + where "xxxxx" identifies the recipient switch. NOA +
+ + is 126. BT uses the dropback scheme in some parts +
+ + of its network. +
+-------------+----------------------------------------------------+
+ US + Uses ACQ. "Location Routing Number (LRN)" is used +
+ + in the Called Party Number parameter. Called party+
+ + number is carried in the Generic Address Parameter +
+ + Use a PNTI indicator in the Forward Call Indicator +
+ + parameter to indicate that NPDB dip has been +
+ + performed. +
+-------------+----------------------------------------------------+
In addition to porting numbers NP provides the ability for number administrators to assign numbering resources to operators in smaller increments. Today it is common for numbering resources to be assigned to telephone operators in a large block of consecutive telephone numbers (TNs). For example, in North America each of these blocks contains 10,000 TNs and is of the format NXX+0000 to NXX+9999. Operators are assigned a specific NXX, or block. That operator is referred to as the block holder. In that block there are 10,000 TNs with line numbers ranging from 0000 to 9999.
除了移植数字之外，NP还为数字管理员提供了以较小增量将数字资源分配给操作员的能力。今天，在一大块连续电话号码（TNs）中分配给电话接线员的资源编号是很常见的。例如，在北美，这些块中的每个块都包含10000 TNs，格式为NXX+0000到NXX+9999。操作员被指定一个特定的NXX或块。该运算符称为块保持器。该区块有10000个TN，行号从0000到9999不等。
Instead of assigning an entire block to the operator, NP allows the administrator to assign a sub-block or even an individual telephone number. This is referred to as block pooling and individual telephone number (ITN) pooling, respectively.
NP允许管理员分配子块甚至单个电话号码，而不是将整个块分配给操作员。这分别称为块池和个人电话号码（ITN）池。
Block Pooling refers to the process whereby the number administrator assigns a range of numbers defined by a logical sub-block of the existing block. Using North America as an example, block pooling would allow the administrator to assign sub-blocks of 1,000 TNs to multiple operators. That is, NXX+0000 to NXX+0999 can be assigned to operator A, NXX+1000 to NXX+1999 can be assigned to operator B, NXX-2000 to 2999 can be assigned to operator C, etc. In this example, block pooling divides one block of 10,000 TNs into ten blocks of 1,000 TNs.
块池是指数字管理员分配由现有块的逻辑子块定义的数字范围的过程。以北美为例，区块池将允许管理员将1000 TN的子区块分配给多个运营商。也就是说，NXX+0000到NXX+0999可以分配给操作员A，NXX+1000到NXX+1999可以分配给操作员B，NXX-2000到2999可以分配给操作员C，等等。在本例中，块池将10000 tn的一个块划分为1000 tn的十个块。
Porting the sub-blocks from the block holder enables block pooling. Using the example above, operator A is the block holder, as well as the holder of the first sub-block, NXX+0000 to NXX+0999. The second sub-block, NXX+1000 to NXX+1999, is ported from operator A to operator B. The third sub-block, NXX+2000 to NXX+2999, is ported from operator A to operator C, and so on. NP administrative processes and call processing will enable proper and efficient routing.
从块保持器移植子块可启用块池。使用上面的示例，运算符A是块保持器，也是第一个子块NXX+0000到NXX+0999的保持器。第二个子块NXX+1000到NXX+1999从操作员A移植到操作员B。第三个子块NXX+2000到NXX+2999从操作员A移植到操作员C，依此类推。NP管理流程和呼叫处理将实现正确有效的路由。
From a number administration and NP administration perspective, block pooling introduces a new concept, that of the sub-block holder. Block pooling requires coordination between the number administrator, the NP administrator, the block holder, and the sub-block holder. Block pooling must be implemented in a manner that allows for NP within the sub-blocks. Each TN can have a different serving operator, sub-block holder, and block holder.
从数字管理和NP管理的角度来看，区块池引入了一个新概念，即子区块持有人。区块池需要号码管理员、NP管理员、区块持有人和子区块持有人之间的协调。块池必须以允许子块内NP的方式实现。每个TN可以有不同的服务操作员、子块保持器和块保持器。
ITN pooling refers to the process whereby the number administrator assigns individual telephone numbers to operators. Using the North American example, one block of 10,000 TNs can be divided into 10,000 ITNs. ITN is more commonly deployed in freephone services.
ITN池是指号码管理员将单个电话号码分配给操作员的过程。以北美为例，10000个TNs的一个区块可分为10000个ITN。ITN通常部署在免费电话服务中。
In ITN the block is not assigned to an operator but to a central administrator. The administrator then assigns ITNs to operators. NP administrative processes and call processing will enable proper and efficient routing.
在ITN中，块不是分配给操作员，而是分配给中央管理员。然后，管理员将ITN分配给操作员。NP管理流程和呼叫处理将实现正确有效的路由。
There are three general areas of impact to IP telephony works-in-progress with the IETF:
IETF正在进行的IP电话工程一般有三个方面的影响：
- Interoperation between NP in GSTN and IP telephony - NP implementation or emulation in IP telephony - Interconnection to NP administrative environment
- GSTN中的NP和IP电话之间的互操作.IP电话中的NP实现或仿真.与NP管理环境的互连
A good understanding of how number portability is supported in the GSTN is important when addressing the interworking issues between IP-based networks and the GSTN. This is especially important when the IP-based network needs to route the calls to the GSTN. As shown in Section 5, there are a variety of standards with various protocol stacks for the switch-to-NPDB interface. Furthermore, the national variations of the protocol standards make it very complicated to deal with in a global environment. If an entity in the IP-based network needs to query those existing NPDBs for routing number information to terminate the calls to the destination GSTN, it would be an
在解决基于IP的网络和GSTN之间的互通问题时，充分了解GSTN中如何支持号码可移植性非常重要。当基于IP的网络需要将呼叫路由到GSTN时，这一点尤为重要。如第5节所示，对于切换到NPDB接口，有各种标准和各种协议栈。此外，议定书标准的国家差异使得在全球环境中处理变得非常复杂。如果基于IP的网络中的实体需要查询这些现有NPDB的路由号码信息以终止对目标GSTN的呼叫，那么它将是一个
impractical, if not impossible, job for that entity to support all those interface standards to access the NPDBs in many countries.
对于该实体来说，支持所有这些接口标准以访问许多国家的NPDB是不切实际的，如果不是不可能的话。
Several alternatives may address this particular problem. One alternative is to use certain entities in the IP-based networks for dealing with NP query, similar to the International Switches that are used in the GSTN to interwork different national ISUP variations. This will force signaling information associated with the calls to certain NP-capable networks in the terminating GSTN to be routed to those IP entities that support the NP functions. Those IP entities then query the NPDBs in the terminating country. This will limit the number of NPDB interfaces that certain IP entities need to support. Another alternative can be to define a "common" interface to be supported by all the NPDBs so that all the IP entities use that standardized protocol to query them. The existing NPDBs can support this additional interface, or new NPDBs that contain the same information but support the common IP interface can be deployed. The candidates for such a common interface include ENUM (telephone number mapping) [ENUM], Lightweight Directory Access Protocol (LDAP) and SIP [SIP] (e.g., using the SIP redirection capability). Certainly another possibility is to use an interworking function to convert from one protocol to another.
有几种备选方案可以解决这一特殊问题。一种替代方法是使用基于IP的网络中的某些实体来处理NP查询，类似于GSTN中用于互通不同国家ISUP变体的国际交换机。这将强制将与对终端GSTN中某些支持NP的网络的呼叫相关联的信令信息路由到那些支持NP功能的IP实体。然后，这些IP实体查询终止国家/地区的NPDB。这将限制某些IP实体需要支持的NPDB接口的数量。另一种选择是定义一个由所有NPDB支持的“公共”接口，以便所有IP实体使用该标准化协议来查询它们。现有的NPDB可以支持此附加接口，或者可以部署包含相同信息但支持公共IP接口的新NPDB。此类公共接口的候选接口包括ENUM（电话号码映射）[ENUM]、轻量级目录访问协议（LDAP）和SIP[SIP]（例如，使用SIP重定向能力）。当然，另一种可能性是使用互通功能从一个协议转换到另一个协议。
IP-based networks can handle the domestic calls between two GSTNs. If the originating GSTN has performed NPDB query, SIP will need to transport and make use of some of the ISUP signaling information even if ISUP signaling may be encapsulated in SIP. Also, IP-based networks may perform the NPDB queries, as the N-1 carrier. In that case, SIP also needs to transport the NP related information while the call is being routed to the destination GSTN. There are three pieces of NP related information that SIP needs to transport. They are 1) the called directory number, 2) a routing number, and 3) a NPDB dip indicator. The NPDB dip indicator is needed so that the terminating GSTN will not perform another NPDB dip. The routing number is needed so that it is used to route the call to the destination network or switch in the destination GSTN. The called directory number is needed so that the terminating GSTN switch can terminate the call. When the routing number is present, the NPDB dip indicator may not be present because there are cases where the routing number is added for routing the call even if NP is not involved. One issue is how to transport the NP related information via SIP. The SIP Universal Resource Locator (URL) is one mechanism. Another better choice may be to add an extension to the "tel" URL [TEL] that is also supported by SIP. Please see [TELNP] for the proposed extensions to the "tel" URL to support NP and freephone service. Those extensions to the "tel" URL will be automatically supported by SIP because they can be carried as the optional parameters in the user portion of the "sip" URL.
基于IP的网络可以处理两个GSTN之间的国内呼叫。如果发起的GSTN已经执行了NPDB查询，那么即使ISUP信令可以封装在SIP中，SIP也需要传输和使用一些ISUP信令信息。此外，基于IP的网络可以作为N-1载波执行NPDB查询。在这种情况下，SIP还需要在呼叫路由到目的地GSTN时传输与NP相关的信息。SIP需要传输三条与NP相关的信息。它们是1）被叫目录号，2）路由号，3）NPDB dip指示器。需要NPDB dip指示器，以便终端GSTN不会执行另一个NPDB dip。需要路由号码，以便将呼叫路由到目的地GSTN中的目的地网络或交换机。需要被叫目录号，以便终止GSTN交换机可以终止呼叫。当存在路由号码时，NPDB dip指示器可能不存在，因为在某些情况下，即使不涉及NP，也会添加路由号码以路由呼叫。一个问题是如何通过SIP传输NP相关信息。SIP通用资源定位器（URL）是一种机制。另一个更好的选择可能是向SIP也支持的“tel”URL[tel]添加扩展。有关支持NP和免费电话服务的“电话”URL的拟议扩展，请参见[TELNP]。SIP将自动支持“tel”URL的这些扩展，因为它们可以作为“SIP”URL的用户部分中的可选参数携带。
For a called directory number that belongs to a country that supports NP, and if the IP-based network is expected to perform the NPDB query, the logical step is to perform the NPDB dip first to retrieve the routing number and use that routing number to select the correct IP telephony gateways that can reach the serving switch that serves the called directory number. Therefore, if the "rn" parameter is present in the "tel" URL or sip URL in the SIP INVITE message, it, instead of the called directory number, should be used for making routing decisions assuming that no other higher priority routing-related parameters such as the "cic" (Carrier Identification Code) are present. If "rn" (Routing Number) is not present, then the dialed directory number can be used as the routing number for making routing decisions.
对于属于支持NP的国家/地区的被叫目录号，如果基于IP的网络需要执行NPDB查询，逻辑步骤是首先执行NPDB dip以检索路由号码，并使用该路由号码选择可以到达为被叫目录号码提供服务的服务交换机的正确IP电话网关。因此，如果“rn”参数存在于sip INVITE消息中的“tel”URL或sip URL中，则应使用它而不是被调用的目录号来做出路由决策，假设不存在其他更高优先级的路由相关参数，例如“cic”（载波标识码）。如果“rn”（路由号码）不存在，则所拨的目录号码可以用作路由号码，用于做出路由决策。
Telephony Routing Information Protocol (TRIP) [TRIP] is a policy driven inter-administrative domain protocol for advertising the reachability of telephony destinations between location servers, and for advertising attributes of the routes to those destinations. With the NP in mind, it is very important to know, that if present, it is the routing number, not the called directory number, that should be used to check against the TRIP tables for making the routing decisions.
电话路由信息协议（TRIP）[TRIP]是一种策略驱动的跨管理域协议，用于在位置服务器之间公布电话目的地的可达性，以及公布到这些目的地的路由属性。考虑到NP，非常重要的是要知道，如果存在，应该使用路由号而不是被调用的目录号来检查行程表，以便做出路由决策。
Overlap signaling exists in the GSTN today. For a call routing from the originating GSTN to the IP-based network that involves overlap signaling, NP will impact the call processing within the IP-based networks if they must deal with the overlap signaling. The entities in the IP-based networks that are to retrieve the NP information (e.g., the routing number) must collect a complete called directory number information before retrieving the NP information for a ported number. Otherwise, the information retrieval won't be successful. This is an issue for the IP-based networks if the originating GSTN does not handle the overlap signaling by collecting the complete called directory number.
如今，GSTN中存在重叠信号。对于从始发GSTN到涉及重叠信令的基于IP的网络的呼叫路由，如果NP必须处理重叠信令，则NP将影响基于IP的网络内的呼叫处理。基于IP的网络中要检索NP信息（例如，路由号码）的实体必须在检索端口号码的NP信息之前收集完整的被叫目录号码信息。否则，信息检索将不会成功。如果原始GSTN不通过收集完整的被叫目录号来处理重叠信令，则这是基于IP的网络的一个问题。
The IETF enum working group is defining the use of the Domain Name System (DNS) for identifying available services and/or Internet resources associated with a particular E.164 number. [ENUMPO] outlines the principles for the operation of a telephone number service that resolves telephone numbers into Internet domain name addresses and service-specific directory discovery. [ENUMPO] implements a three-level approach where the first level is the mapping of the telephone number delegation tree to the authority to which the number has been delegated, the second level is the provision of the requested DNS resource records from a service registrar, and the third level is the provision of service specific data from the service provider itself. NP certainly must be considered at the first level because the telephony service providers
IETF enum工作组正在定义域名系统（DNS）的使用，以识别与特定E.164号码相关的可用服务和/或互联网资源。[ENUMPO]概述了电话号码服务的操作原则，该服务将电话号码解析为Internet域名地址和特定于服务的目录发现。[ENUMPO]实施三级方法，其中第一级是将电话号码授权树映射到该号码已被授权的机构，第二级是从服务注册机构提供请求的DNS资源记录，第三个层次是从服务提供商自身提供特定于服务的数据。NP当然必须在第一级考虑，因为电话服务提供商
do not "own" or control the telephone numbers under the NP environment; therefore, they may not be the proper entities to have the authority for a given E.164 number. Not only that, there is a regulatory requirement on NP in some countries that the donor network should not be relied on to reach the delegated authority during the DNS process. The delegated authority for a given E.164 number is likely to be an entity designated by the end user that owns/controls a specific telephone number, or one that is designated by the service registrar.
不要在NP环境下“拥有”或控制电话号码；因此，他们可能不是拥有给定E.164编号权限的适当实体。不仅如此，一些国家对NP有一项监管要求，即在DNS过程中，不应依靠捐赠网络获得授权。给定E.164号码的授权可能是由拥有/控制特定电话号码的最终用户指定的实体，或由服务注册机构指定的实体。
Since the telephony service providers may have the need to use ENUM for their network-related services (e.g., map an E.164 number to a HLR Identifier in the wireless networks), their ENUM records must be collocated with those of the telephony subscribers. If that is the case, NP will impact ENUM when a telephony subscriber who has ENUM service changes the telephony service provider. This is because that the ENUM records from the new telephony service provider must replace those from the old telephony service provider. To avoid the NP impact on ENUM, it is recommended that the telephony service providers use a different domain tree for their network-related service. For example, if e164.arpa is chosen for "end user" ENUM, a domain tree different from e164.arpa should be used for "carrier" ENUM.
由于电话服务提供商可能需要为其网络相关服务使用ENUM（例如，将e.164号码映射到无线网络中的HLR标识符），因此其ENUM记录必须与电话订户的ENUM记录并置。如果是这种情况，当拥有ENUM服务的电话用户更改电话服务提供商时，NP将影响ENUM。这是因为来自新电话服务提供商的枚举记录必须替换来自旧电话服务提供商的枚举记录。为避免NP对ENUM的影响，建议电话服务提供商为其网络相关服务使用不同的域树。例如，如果为“最终用户”枚举选择了e164.arpa，则应为“运营商”枚举使用与e164.arpa不同的域树。
The IP-based networks also may need to support some forms of number portability in the future if E.164 numbers are assigned to the IP-based end users. One method is to assign a GSTN routing number for each IP-based network domain or entity in a NP-capable country. This may increase the number of digits in the routing number to incorporate the IP entities and impact the existing routing in the GSTN. Another method is to associate each IP entity with a particular GSTN gateway. At that particular GSTN gateway, the called directory number is then used to locate the IP-entity that serves that dialed directory number. Yet, another method can be to assign a special routing number so that the call to an end user currently served by an IP entity is routed to the nearest GSTN gateway. The called directory number then is used to locate the IP-entity that serves that dialed directory number. A mechanism can be developed or used for the IP-based network to locate the IP entity that serves a particular dialed directory number. Many other types of networks use E.164 numbers to identify the end users or terminals in those networks. Number portability among GSTN, IP-based network, and those various types of networks may also need to be supported in the future.
如果将E.164号码分配给基于IP的最终用户，则基于IP的网络将来可能还需要支持某些形式的号码可移植性。一种方法是为具有NP能力的国家/地区的每个基于IP的网络域或实体分配GSTN路由号码。这可能会增加路由号码中的位数，以合并IP实体，并影响GSTN中的现有路由。另一种方法是将每个IP实体与特定的GSTN网关相关联。在该特定的GSTN网关上，被叫目录号随后被用来定位为该拨号目录号提供服务的IP实体。然而，另一种方法可以是分配特殊的路由号码，以便将当前由IP实体服务的对最终用户的呼叫路由到最近的GSTN网关。然后，调用的目录号用于定位为该拨号目录号提供服务的IP实体。可以为基于IP的网络开发或使用一种机制来定位服务于特定拨号目录号的IP实体。许多其他类型的网络使用E.164编号来识别这些网络中的最终用户或终端。将来可能还需要支持GSTN、基于IP的网络以及那些不同类型的网络之间的号码可移植性。
In the PSTN, the NPDB queries are generated by the PSTN switches and carried over the SS7 networks to reach the NPDBs and back to the switches. The SS7 networks are operated by telecommunications operators and signaling transport service providers in such a closed environment that make them difficult for the hackers to penetrate. However, when VoIP operators need the NP information and have to launch the NP queries from their softswitches, media gateway controllers or call managers, there would be security concerns if the NP queries and responses are transported over the Internet. If the routing number or routing prefix in the response is altered during the message transport, the call will be routed to the wrong place. It is recommended that the NPDB queries be transported via a secure transport layer or with added security mechanisms to ensure the data integrity.
在PSTN中，NPDB查询由PSTN交换机生成，并通过SS7网络传送到NPDB并返回到交换机。SS7网络由电信运营商和信号传输服务提供商在这样一个封闭的环境中运营，使得黑客难以渗透。然而，当VoIP运营商需要NP信息并且必须从其软交换机、媒体网关控制器或呼叫管理器启动NP查询时，如果NP查询和响应通过Internet传输，则会存在安全问题。如果在消息传输过程中更改了响应中的路由号码或路由前缀，则呼叫将被路由到错误的位置。建议通过安全传输层或添加安全机制传输NPDB查询，以确保数据完整性。
This document introduces no new values for IANA registration.
本文档没有为IANA注册引入新值。
[ANSI OSS] ANSI Technical Requirements No. 1, "Number Portability - Operator Services Switching Systems," April 1999.
[ANSI OSS]第1号ANSI技术要求，“号码可移植性-运营商服务交换系统”，1999年4月。
[ANSI SS] ANSI Technical Requirements No. 2, "Number Portability - Switching Systems," April 1999.
[ANSI SS]第2号ANSI技术要求，“号码可移植性-交换系统”，1999年4月。
[ANSI DB] ANSI Technical Requirements No. 3, "Number Portability Database and Global Title Translation," April 1999.
[ANSI DB]第3号ANSI技术要求，“数字可移植性数据库和全球标题翻译”，1999年4月。
[CS1] ITU-T Q-series Recommendations - Supplement 4, "Number portability Capability set 1 requirements for service provider portability (All call query and onward routing)," May 1998.
[CS1]ITU-T Q系列建议-补充件4，“号码可移植性能力集1对服务提供商可移植性（所有呼叫查询和转发路由）的要求”，1998年5月。
[CS2] ITU-T Q-series Recommendations - Supplement 5, "Number portability -Capability set 2 requirements for service provider portability (Query on release and Dropback)," March 1999.
[CS2]ITU-T Q系列建议-补充件5，“号码可移植性-服务提供商可移植性的能力集2要求（发布和回退查询）”，1999年3月。
[E164] ITU-T Recommendation E.164, "The International Public Telecommunications Numbering Plan," 1997.
[E164]ITU-T建议E.164，“国际公共电信编号计划”，1997年。
[ENUM] Falstrom, P., "E.164 number and DNS", RFC 2916, September 2000.
[ENUM]Falstrom，P.，“E.164数字和DNS”，RFC 29162000年9月。
[ETSIISUP] ETSI EN 302 097 V.1.2.2, Integrated Services Digital Network (ISDN); Signalling System No.7 (SS7); ISDN User Part (ISUP); Enhancement for support of Number Portability (NP) [ITU-T Recommendation Q.769.1 (2000), modified]
[ETSIISUP]ETSI EN 302 097 V.1.2.2，综合业务数字网（ISDN）；七号信令系统（SS7）；ISDN用户部分（ISUP）；增强对号码可移植性（NP）的支持[ITU-T建议Q.769.1（2000），修改]
[GSM] GSM 09.02: "Digital cellular telecommunications system (Phase 2+); Mobile Application Part (MAP) specification".
[GSM]GSM 09.02：“数字蜂窝通信系统（第2+阶段）；移动应用部分（MAP）规范”。
[IS41] TIA/EIA IS-756 Rev. A, "TIA/EIA-41-D Enhancements for Wireless Number Portability Phase II (December 1998), "Number Portability Network Support," April 1998.
[IS41]TIA/EIA IS-756修订版。A、 “TIA/EIA-41-D无线号码可携性增强第二阶段（1998年12月），“号码可携性网络支持”，1998年4月。
[ITUISUP] ITU-T Recommendation Q.769.1, "Signaling System No. 7 - ISDN User Part Enhancements for the Support of Number Portability," December 1999.
[ITUISUP]ITU-T建议Q.769.1，“第7号信令系统-支持号码可移植性的ISDN用户部分增强”，1999年12月。
[MNP] ETSI EN 301 716 (2000-10) European Standard (Telecommunications series) Digital cellular telecommunications system (Phase 2+); Support of Mobile Number Portability (MNP); Technical Realisation; Stage 2; (GSM 03.66 Version 7.2.0 Release 1998).
[MNP]ETSI EN 301 716（2000-10）欧洲标准（电信系列）数字蜂窝通信系统（第2+阶段）；支持移动电话号码可携性（MNP）；技术实现；第二阶段；（GSM 03.66版本7.2.0 1998年发布）。
[RFC] Bradner, S., "The Internet Standards Process -- Revision 3", BCP 9, RFC 2026, October 1996.
[RFC]Bradner，S.，“互联网标准过程——第3版”，BCP 9，RFC 2026，1996年10月。
[ENUMPO] Brown A. and G. Vaudreuil, "ENUM Service Specific Provisioning: Principles of Operations", Work in Progress.
[ENUMPO]Brown A.和G.Vaudreuil，“ENUM服务特定配置：操作原则”，正在进行中。
[SIP] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A., Peterson, J., Sparks, R., Handley, M. and E. Schooler, "SIP: Session Initiation Protocol", RFC 3461, June 2002.
[SIP]Rosenberg，J.，Schulzrinne，H.，Camarillo，G.，Johnston，A.，Peterson，J.，Sparks，R.，Handley，M.和E.Schooler，“SIP：会话启动协议”，RFC 34612002年6月。
[TEL] Schulzrinne, H. and A. Vaha-Sipila, "URIs for Telephone Calls", Work in Progress.
[电话]Schulzrinne，H.和A.Vaha Sipila，“电话呼叫的URI”，正在进行中。
[TELNP] Yu, J., "Extensions to the "tel" URL to support Number Portability and Freephone Service", Work in Progress.
[TELNP]Yu，J.，“支持号码可携性和免费电话服务的“电话”URL扩展”，正在进行中。
[TRIP] Rosenberg, J., Salama, H. and M. Squire, "Telephony Routing Information Protocol (TRIP)", RFC 3219, January 2002.
[TRIP]Rosenberg，J.，Salama，H.和M.Squire，“电话路由信息协议（TRIP）”，RFC 3219，2002年1月。
The authors would like to thank Monika Muench for providing information on ISUP and MNP.
作者感谢Monika Muench提供有关ISUP和MNP的信息。
Mark D. Foster NeuStar, Inc. 46000 Center Oak Plaza Sterling, VA 20166 United States
Mark D.Foster NeuStar，Inc.美国弗吉尼亚州斯特林中心橡木广场46000号，邮编20166
Phone: +1-571-434-5410
Fax: +1-571-434-5401
EMail: mark.foster@neustar.biz
Phone: +1-571-434-5410
Fax: +1-571-434-5401
EMail: mark.foster@neustar.biz
Tom McGarry NeuStar, Inc. 46000 Center Oak Plaza Sterling, VA 20166 United States
Tom McGarry NeuStar，Inc.美国弗吉尼亚州斯特林中心橡木广场46000号，邮编20166
Phone: +1-571-434-5570
Fax: +1-571-434-5401
EMail: tom.mcgarry@neustar.biz
Phone: +1-571-434-5570
Fax: +1-571-434-5401
EMail: tom.mcgarry@neustar.biz
James Yu NeuStar, Inc. 46000 Center Oak Plaza Sterling, VA 20166 United States
James Yu NeuStar，Inc.美国弗吉尼亚州斯特林中心橡木广场46000号，邮编20166
Phone: +1-571-434-5572
Fax: +1-571-434-5401
EMail: james.yu@neustar.biz
Phone: +1-571-434-5572
Fax: +1-571-434-5401
EMail: james.yu@neustar.biz
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Acknowledgement
确认
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