2.5 Addressing and identities / 寻址和身份

2.5.1 Overview / 概述

Telephone numbers in the legacy address book must be usable (regardless of whether RCS contacts have been enriched or not) for the identification of contacts of incoming and outgoing SIP requests.
传统通讯录中的电话号码必须可用（无论是否富RCS联系人）用于识别传入和传出SIP请求的联系人。

Also, RCS users, especially in Enterprise segments, may be assigned a non MSISDN based identity. The RCS client would in that case be provisioned with only the appropriate SIP URI parameter as seen in section 2.2.1.1.2 of [PRD-RCC.15], leaving the tel URI parameter empty.
此外，RCS用户，特别是在企业段中，可以被分配非基于MSISDN的身份。在这种情况下，RCS客户端将仅提供适当的SIP URI参数，如[PRD-RCC.15]的2.2.1.1.2节所示，将tel URI参数留空。

Consequently, an RCS enabled terminal’s address book should also be able to store alphanumeric SIP URIs as part of a contact’s details.
因此，启用RCS的终端地址簿还应该能够存储字母数字SIP URI作为联系人的细节的一部分。

NOTE1: The handling of identities described in this section applies also to IP Voice Calls [PRD-IR.92] and [PRD-IR.51]. The functionality described here comes in addition to the functionality described in the related Permanent Reference Documents (PRDs), but not in conflict with them, e.g. the alias handling described in section 2.5.3.4.
注1：本节中描述的身份的处理也适用于IP语音呼叫[PRD-IR.92]和[PRD-IR.51]。这里所描述的功能是作为相关的永久参考文献（PRD）中描述的功能的补充，而非与之冲突，例如第2.5.3.4节中所描述的别名处理。

NOTE2: The identification in Common Profile for Instant Messaging (CPIM) headers is discussed in section 3.3 and 3.4.
注2：在公共配置文件中的即时消息（CPIM）头的标识在第3.3和3.4节中讨论。

2.5.2 Device Incoming SIP Request / 设备接入SIP请求

2.5.2.1 From/P-Asserted-Identity

For device incoming SIP requests, the address(es) of the contact are, depending on the type of request, provided as a URI in the body of a request or contained in the P-Asserted- Identity and/or the From headers. If the P-Asserted-Identity header is present, the From header will be ignored. The only exception to this rule is when a request for Chat or Standalone Messaging includes a Referred-By header (it is initiated by Messaging Server for example in a store and forward use case as described in 3.3.4.1.4), thereby the Referred-By header should be used to retrieve the originating user instead.
对于设备传入SIP请求，根据请求的类型，联系人的地址被提供作为请求的主体中的URI或包含在P-Asserted-Identity和/或From报头中。如果存在P-Asserted-Identity报头，则将忽略From报头。此规则的唯一例外是当对聊天或独立消息的请求包括Referred-By头（它由消息服务器发起，例如在3.3.4.1.4中所述的存储和转发用例中）时，此时应该使用Referred-By头代替来取回发起用户。

The receiving client will try to extract the contact’s phone number out of the following types of URIs:
接收客户端将尝试从以下类型的URI中提取联系人的电话号码：

tel URIs (telephone URIs, for example tel:+1234578901, or tel:2345678901;phone- context=)
tel URI（电话URI，例如tel：+1234578901或tel：2345678901; phone-context = ）
SIP URIs with a “user=phone” parameter, the contact’s phone number will be provided in the user part (for example sip:[email protected];user=phone or sip:1234578901;phone-context=<phonecontextvalue>@operator.com;user=phone)
具有“user=phone”参数的SIP URI，联系人的电话号码将在用户部分中提供（例如sip:[email protected]; user=phone或sip:1234578901;phone-context=<phonecontextvalue>@operator.com;user=phone）

Once the MSISDN is extracted, it will be matched against the phone number of the contacts stored in the address book. If the received URI is a SIP URI but does not contain the “user=phone” parameter, the incoming identity should be checked against the SIP and tel URI address of the contacts in the address book instead.
一旦MSISDN被提取，它将与存储在地址簿中的联系人的电话号码匹配。如果接收到的URI是SIP URI，但不包含“user=phone”参数，则应根据地址簿中联系人的SIP和tel URI地址来检查传入身份。

If more than one P-Asserted-Identity is received in the message, all identities shall be processed until a matched contact is found.
如果在消息中接收到多个P-Asserted-Identity，则应处理所有身份，直到找到匹配的联系人。

2.5.2.2 In-call SIP requests / 呼叫中SIP请求

2.5.2.2.1 Caller: relating the ongoing call with in-call incoming SIP requests / 呼叫者：关联正在进行的呼叫呼入传入SIP请求

The destination identity of the telephony call that the caller dials or gets from his address book and the originator identity of any in-call incoming request may be in various formats. The client of the caller shall, therefore, apply the following matching mechanism to determine whether an incoming request relates to the ongoing call:
呼叫者从他的地址簿拨打或获得的电话呼叫的目的地身份和任何来电呼入请求的发起者身份可以是各种格式。因此，呼叫者的客户端应用以下匹配机制来确定进入的请求是否与正在进行的呼叫有关：

If both the destination identity of the telephony call and the originator identity of the in-call incoming request are phone numbers in international format, the client of the caller shall compare all digits of the provided numbers to determine whether they match.
如果电话呼叫的目的地标识和呼入呼入请求的发起者标识都是国际格式的电话号码，则呼叫者的客户端应比较提供的号码的所有数字以确定它们是否匹配。
If any of the identities is not in international format, the client of the caller shall apply an enhanced matching mechanism between the destination identity from the telephony call and the originator identity of the incoming request, e.g. by comparing the 7 digits starting from the end of the number. It is left to the client implementation to apply an even more enhanced matching algorithm to decrease the probability of false matches.
如果任何身份不是国际格式，则呼叫者的客户端应在来自电话呼叫的目的地身份和来话请求的始发者身份之间应用增强的匹配机制。通过比较从数字的结尾开始的7个数字。留给客户端实现来应用甚至更加增强的匹配算法以降低错误匹配的概率。

The client shall consider the identities to be in international format if
在以下情况下，客户应考虑国际格式的身份

For a CS or multimedia telephony outgoing call, the digits dialled or taken from the address book start with a “+”.
对于CS或多媒体电话拨出呼叫，从地址簿拨出或取出的数字以“+”开头。
Tor an incoming request, the P-Asserted-Identity of the SIP request contains either:
对于传入请求，SIP请求的P-Asserted-Identity包含以下之一：
- a tel URI starting with a “+” without phone-context i.e. a global number, or
  一个以“+”开头而没有电话上下文的tel URI。全局编号或
- a SIP URI with user part starting with a “+”, a user=phone parameter and without a phone-context parameter in the user part.
  具有用户部分以“+”，用户=电话参数开始并且在用户部分中没有电话上下文参数的SIP URI。

Examples:
例子：

The destination identity of the outgoing telephony call: +447123456789 (display string for an international format number).
呼出电话呼叫的目的地标识：+447123456789（显示国际格式编号的字符串）。
The originator identity of the incoming request: +447123456789
呼入请求的发起者身份：+447123456789
=> Matching result: Successful
=> 匹配结果：成功

When the applied enhanced matching algorithm is based on the 7 digits starting from the end of the number:
当应用的增强匹配算法基于从数字的结尾开始的7个数字：
The destination identity of the outgoing telephony call: 07123456789 (non- international format).
呼出电话呼叫的目的地标识：07123456789（非国际格式）。
The originator identity of the incoming request: +447123456789
呼入请求的发起者身份：+447123456789
=> Matching result: Successful
=> 匹配结果：成功

2.5.2.2.2 Callee: relating the ongoing call with in-call incoming SIP requests / 被叫方：关联正在进行的呼叫呼入传入SIP请求

The originator identity of the telephony call and the originator identity of any in-call incoming request may be provided in various formats both in the home networks and when roaming. The client of the callee shall therefore apply the following matching mechanism to determine whether an incoming request relates to the ongoing call:
电话呼叫的始发者身份和任何来电呼入请求的始发者身份可以在家庭网络中和漫游时以各种格式提供。因此，被叫方的客户机应用以下匹配机制来确定进入的请求是否与正在进行的呼叫有关：

If both the originator identity of the telephony call and the originator identity of the in- call incoming request are phone numbers in international format, the client of the callee shall compare all digits of the provided numbers to determine whether they match.
如果电话呼叫的发起者身份和呼入呼入请求的发起者身份都是国际格式的电话号码，则被叫者的客户端应比较所提供的号码的所有数字以确定它们是否匹配。
If any of the originator identities is not in international format, the client of the callee shall apply an enhanced matching mechanism between the originator identity from the telephony call and the originator identity of the incoming request, e.g. by comparing the 7 digits starting from the end of the number. It is left to the client implementation to apply an even more enhanced matching algorithm to decrease the probability of false matches.
如果任何始发者身份不是国际格式，则被叫者的客户端将在来自电话呼叫的始发者身份和来话请求的始发者身份之间应用增强的匹配机制。通过比较从数字的结尾开始的7个数字。留给客户端实现来应用甚至更加增强的匹配算法以降低错误匹配的概率。

The client shall consider the identities to be in international format if
在以下情况下，客户应考虑国际格式的身份

For a CS incoming call, the Type Of Number (TON) of the Calling Party BCD Number is set to “international” as defined in [3GPP TS 24.008].
对于CS呼入呼叫，如[3GPP TS 24.008]中所定义的，主叫方BCD号码的号码类型（TON）被设置为“国际”。
For a multimedia telephony incoming call, the P-Asserted-Identity of the SIP INVITE request contains either:
对于多媒体电话呼入，SIP INVITE请求的P-Asserted-Identity包含：
- tel URI starting with a “+” without phone-context i.e. a global number or
  tel URI以“+”开头，没有电话上下文即全局号码或
- SIP URI with user part starting with a “+”, a user=phone parameter and without a phone-context parameter in the user part.
  SIP URI，用户部分以“+”，用户=电话参数开始，在用户部分中没有电话上下文参数。
For an incoming request, the P-Asserted-Identity of the SIP request contains either:
对于传入请求，SIP请求的P-Asserted-Identity包含以下之一：
- a tel URI starting with a “+” without phone-context i.e. a global number or
  一个以“+”开头而没有电话上下文即全局号码的tel URI或
- a SIP URI with user part starting with a “+”, a user=phone parameter and without a phone-context parameter in the user part.
  具有用户部分以“+”，用户=电话参数开始并且在用户部分中没有电话上下文参数的SIP URI。

Examples:
例子：

The originator identity of the incoming telephony call: +447123456789 (display string for an international format number).
来电电话呼叫的发起人身份：+447123456789（显示国际格式编号的字符串）。
The originator identity of the incoming request: +447123456789
传入请求的发起者身份：+447123456789
=> Matching result: Successful
=> 匹配结果：成功

2.5.3 Device Outgoing SIP Request / 设备发出的SIP请求

2.5.3.1 Identification of the target contact / 识别目标联系人

If the target contact contains a SIP or tel URI the value shall be used by the RCS client when generating the outgoing request even if an MSISDN is also present for the contact. This applies to the SIP Request-URI and the “To” header (as defined in [3GPP TS 24.229]) for 1-to-1 communication, including the URIs used in the recipient list included in outgoing SIP requests for Group Chat.
如果目标联系人包含SIP或tel URI，则在生成外发请求时，RCS客户端将使用该值，即使联系人也存在MSISDN。这适用于用于1对1通信的SIP请求-URI和“To”报头（如[3GPP TS 24.229]中所定义的），包括在用于群聊的输出SIP请求中包括的接收者列表中使用的URI。

If no SIP or tel URI is present the RCS client shall use the telephone number (in local format for example 0234578901 or international format +1234578901) set in the address book or a dial string entered by the user.
如果不存在SIP或tel URI，则RCS客户端将使用在地址簿中设置的电话号码（例如本地格式，例如0234578901或国际格式+1234578901）或用户输入的拨号字符串。

If the target number is an international-format telephone number, the device shall be able to send it as tel URI (for example “tel:+12345678901”) as defined in [RFC3966].
如果目标号码是国际格式的电话号码，则设备将能够将其作为tel URI（例如“tel：+12345678901”）发送，如[RFC 3966]中所定义。

If the target number is a non-international format telephone number, the RCS client shall be able to send it as tel URI with a phone-context value set as defined in [3GPP TS 24.229] for home local numbers (for example tel:0234578901;phone-context=).
如果目标号码是非国际格式的电话号码，则RCS客户端应能够将其作为tel URI发送，具有如[3GPP TS 24.229]中为家庭本地号码定义的电话上下文值集（例如tel：0234578901 ; phone-context = ）。

2.5.3.2 In-call SIP requests / 呼叫中SIP请求

2.5.3.2.1 Caller: addressing SIP requests towards the callee / 调用者：向被调用者寻址SIP请求

The destination identity of the telephony call that the caller dials or gets from the address book may be in various formats. The client of the caller shall, therefore, apply the following principles for addressing the callee when triggers in-call SIP requests:
呼叫者拨打或从地址簿获得的电话呼叫的目的地标识可以是各种格式。因此，当触发呼叫中SIP请求时，呼叫者的客户端应当应用以下原理来寻址被叫者：

If the destination identity of the telephony call is in international format, the client of the caller shall use this information for addressing in-call SIP requests towards the callee.
如果电话呼叫的目的地标识是国际格式，则呼叫者的客户端应使用该信息来寻址到被呼叫者的呼叫中SIP请求。
If the destination identity of the telephony call is not in international format, the client of the caller shall use geo-local numbering of the destination identity of the telephony call for addressing in-call SIP requests towards the callee. If the request fails, the client of the caller shall attempt to correlate the destination identity of the telephony call with his local identity records acquired from incoming SIP requests received in a window prior to the call and/or during the call using an enhanced matching mechanism between the destination identity from the telephony call and the incoming SIP requests, e.g. by comparing the 7 digits starting from the end of the number. It is left to the client implementation to set the time length of the window and apply an even more enhanced matching algorithm to decrease the probability of false matches.
如果电话呼叫的目的地标识不是国际格式，则呼叫者的客户端将使用电话呼叫的目的地标识的地理地方编号来寻址到被呼叫者的呼叫中SIP请求。如果请求失败，则呼叫者的客户端应尝试将电话呼叫的目的地身份与在呼叫之前的窗口中接收到的来自SIP请求的本地身份记录相关联，和/或在呼叫期间使用增强的匹配机制在来自电话呼叫的目的地标识和进入的SIP请求之间，例如，通过比较从数字的结尾开始的7个数字。它留给客户端实现来设置窗口的时间长度，并应用甚至更加增强的匹配算法以降低错误匹配的概率。

a) If there is successful matching, the client of the caller shall use the “matched” destination identity from his local identity records for addressing in-call SIP requests towards the callee.
如果匹配成功，则呼叫者的客户端将使用来自其本地身份记录的“匹配”目的地标识来向被叫方寻址呼叫中SIP请求。
b) If there is no successful matching, the client of the caller shall use the destination identity from the telephony call that the caller dials or gets from his address book for addressing in-call SIP requests towards the callee. The client of the caller shall continue applying the enhanced matching mechanism for any in-call incoming SIP request until it matches the destination identity from the telephony call with the originator identity from an in-call incoming SIP request. Once there is a successful matching it shall from then on use the “matched” originator identity from the SIP request for addressing any future in- call SIP requests towards the callee.
如果没有成功匹配，则呼叫者的客户端将使用来自呼叫者拨打或从其地址簿获得的电话呼叫的目的地身份，用于向被呼叫者寻址呼叫中SIP请求。呼叫者的客户端应继续对任何来电呼入SIP请求应用增强的匹配机制，直到其使来自电话呼叫的目的地身份与来自呼叫的入局SIP请求的发起者身份匹配。一旦成功匹配，它就从那时起使用来自SIP请求的“匹配的”发起者身份，用于向被叫者寻址任何未来的呼叫SIP请求。

The client shall consider the identities to be in international format if
在以下情况下，客户应考虑国际格式的身份

for a CS or multimedia telephony outgoing call, the digits dialled or taken from the address book start with a “+”.
对于CS或多媒体电话输出呼叫，从地址簿拨出或取出的数字以“+”开始。

Examples:
例子：

The destination identity of the outgoing telephony call: +447123456789 (display string for an international format number).
呼出电话呼叫的目的地标识：+447123456789（显示国际格式编号的字符串）。
The client of the caller uses the destination identity from the telephony call for addressing in-call SIP requests towards the callee.
呼叫者的客户端使用来自电话呼叫的目的地标识来寻址到被呼叫者的呼叫中SIP请求。
The enhanced matching mechanism does not apply.
增强的匹配机制不适用。

The destination identity of the outgoing telephony call: 07123456789 (non- international format).
出局电话呼叫的目的地标识：07123456789（非国际格式）。

The client of the caller shall use geo-local numbering of the destination identity of the telephony call for addressing in-call SIP requests towards the callee: tel:07123456789;phone-context=geolocal., where needs to be replaced with the home network domain name as configured by the device (as per section 2.2.3 of [PRD-IR.92]).
呼叫者的客户端将使用电话呼叫的目的地标识的地理地方编号来寻址到被呼叫者的呼叫中SIP请求：tel：07123456789; phone-context = geolocal ，其中需要更换为设备配置的家庭网络域名（按照[PRD-IR.92]第2.2.3节）。
If the in-call SIP request fails, the client shall apply the enhanced matching mechanism.
如果呼叫中的SIP请求失败，客户端应该应用增强的匹配机制。
The originator identity of incoming SIP request: +447123456789.
传入SIP请求的始发者身份：+447123456789。
=> Matching result: Successful
=> 匹配结果：成功

2.5.3.2.2 Callee: addressing SIP requests towards the caller / Callee：向呼叫者寻址SIP请求

The originator identity of the telephony call may be provided in various formats both in the home networks and when roaming. The client of the callee shall therefore apply the following principles for addressing the caller when triggers in-call SIP requests:
电话呼叫的始发者身份可以在家庭网络中和漫游时以各种格式提供。因此，被叫方的客户端应当在触发呼叫中SIP请求时应用以下原则来寻址呼叫者：

If the originator identity of the telephony call is in international format, the client of the callee shall use this information for addressing in-call SIP requests towards the caller.
如果电话呼叫的始发者身份是国际格式，则被叫者的客户端将使用该信息来寻址到呼叫者的呼叫中SIP请求。
If the originator identity of the telephony call is not in international format, the client of the callee shall use geo-local numbering of the originator identity of the telephony call for addressing in-call SIP requests towards the caller. If the request fails, the client of the callee shall attempt to correlate the originator identity of the telephony call with his local identity records acquired from incoming SIP requests received in a window prior to the call and/or during the call using an enhanced matching mechanism between the originator identity from the telephony call and the incoming SIP requests, e.g. by comparing the 7 digits starting from the end of the number. It is left to the client implementation to set the time length of the window and apply an even more enhanced matching algorithm to decrease the probability of false matches.
如果电话呼叫的发起者身份不是国际格式，则被叫者的客户端将使用电话呼叫的发起者身份的地理地方编号来寻址到呼叫者的呼叫中SIP请求。如果请求失败，被叫方的客户端将尝试将电话呼叫的始发者身份与在呼叫之前和/或在呼叫期间在窗口中接收到的来自SIP请求的本地身份记录相关联，使用增强的匹配机制在来自电话呼叫的发起者身份和进入的SIP请求之间，例如，通过比较从数字的结尾开始的7个数字。它留给客户端实现来设置窗口的时间长度，并应用甚至更加增强的匹配算法以降低错误匹配的概率。

a) If there is successful matching, the client of the callee shall use the “matched” originator identity from his local identity records for addressing in-call SIP requests towards the caller.
如果匹配成功，被叫方的客户端将使用来自其本地身份记录的“匹配的”始发者身份来向呼叫者寻址呼叫中的SIP请求。
b) If there is no successful matching, the client of the callee shall use the originator identity from the telephony call for addressing in-call SIP requests towards the caller. The client of the callee shall continue applying the enhanced matching mechanism for any in-call incoming SIP request until it matches the originator identity from the telephony call with the originator identity from an in-call incoming SIP request. Once there is a successful matching it shall from then on use the “matched” originator identity from the SIP request for addressing any future in-call SIP requests towards the caller.
如果没有成功匹配，则被叫方的客户端将使用来自电话呼叫的发起方身份来寻址到呼叫方的呼叫中SIP请求。被叫方的客户端应继续对任何来电呼入SIP请求应用增强的匹配机制，直到其与来自呼叫中的进入SIP请求的发起方身份的来自电话呼叫的发起方身份匹配。一旦成功匹配，它就从那时起使用来自SIP请求的“匹配的”始发者身份，用于向呼叫者寻址任何未来的呼叫中SIP请求。

The client shall consider the identities to be in international format if
在以下情况下，客户应考虑国际格式的身份

for a CS incoming call, the Type Of Number (TON) of the Calling Party BCD Number is set to “international” as defined in [3GPP TS 24.008].
对于CS呼入呼叫，如[3GPP TS 24.008]中所定义的，主叫方BCD号码的号码类型（TON）被设置为“国际”。
for a multimedia telephony incoming call, the P-Asserted-Identity of the SIP INVITE request contains either:
对于多媒体电话呼入，SIP INVITE请求的P-Asserted-Identity包含以下之一：
- a tel URI starting with a “+” without phone-context i.e. a global number or
  一个以“+”开头而没有电话上下文即全球号码的tel URI或
- a SIP URI with user part starting with a “+”, a user=phone parameter and without a phone-context parameter in the user part.
  具有用户部分以“+”，用户=电话参数开始并且在用户部分中没有电话上下文参数的SIP URI。

Examples:
例子：

The originator identity of the incoming telephony call: +447123456789 (display string for an international format number).
呼入电话呼叫的发起者身份：+447123456789（显示国际格式编号的字符串）。
The client of the callee uses the originator identity from the telephony call for addressing in-call SIP requests towards the caller.
被叫方的客户端使用来自电话呼叫的发起方身份来寻址到呼叫方的呼叫中SIP请求。
The enhanced matching mechanism does not apply.
增强的匹配机制不适用。

When the applied enhanced matching algorithm is based on the 7 digits starting from the end of the number:
当应用的增强匹配算法基于从数字的结尾开始的7个数字：
The originator identity of the incoming telephony call: 006447123456789 (non- international format).
呼入电话呼叫的始发者身份：006447123456789（非国际格式）。
The client of the callee shall use geo-local numbering of the originator identity of the telephony call for addressing in-call SIP requests towards the caller: tel: 006447123456789;phone-context=geolocal., where needs to be replaced with the home network domain name as configured by the device (as per section 2.2.3 of [PRD-IR.92]).
被叫方的客户端将使用电话呼叫的发起方身份的地理地方编号来寻址到呼叫方的呼叫中SIP请求：tel：006447123456789; phone-context = geolocal ，其中需要更换为设备配置的家庭网络域名（按照[PRD-IR.92]第2.2.3节）。
If the in-call SIP request fails, the client shall apply the enhanced matching mechanism.
如果呼叫中的SIP请求失败，客户端应该应用增强的匹配机制。
The originator identity of incoming SIP request: +447123456789.
呼入SIP请求的始发者身份：+447123456789。
=> Matching result: Successful
=>匹配结果：成功

2.5.3.3 Self-Identification to the network and the addressed contact / 自我识别到网络和寻址的联系人

When generating an outgoing non-REGISTER request, the RCS client shall populate the From header field and may populate the P-Preferred-Identity header field with a SIP or tel URI which has been received in the P-Associated-URI header field returned in the 200 OK to the SIP REGISTER. If both a SIP URI and a tel URI are available to the RCS client, the tel URI should be used.
当生成传出的非REGISTER请求时，RCS客户端将填充From报头字段，并且可以使用在P-Associated-URI报头字段中接收到的SIP或tel URI来填充P-Preferred-Identity报头字段 200 OK到SIP REGISTER。如果SIP URI和tel URI都可用于RCS客户端，则应使用tel URI。

2.5.3.4 User alias / 用户别名

The user shall be able to specify an alias or a username for RCS services. This information will be sent when establishing a communication service with another user so they are able to receive additional information (i.e. beyond than just a MSISDN), if the originating user is not in the receiver’s address book. This scenario will likely be common with Group Chat sessions.
用户应能够为RCS服务指定别名或用户名。当与另一用户建立通信服务时，将发送该信息，使得如果始发用户不在接收者的地址簿中，则它们能够接收附加信息（即，不仅仅是MSISDN）。此方案可能会与组聊天会话相同。

This alias information will be set in the From header of the SIP request as the display name and in a Group Chat also in the CPIM From header as the formal name.
此别名信息将在SIP请求的From头中作为显示名称设置，并在Group Chat中也在CPIM From头中设置为正式名称。

When receiving a request, the RCS client device shall follow the rules explained in section 2.5.2.1 and extract the MSISDN or SIP URI. To avoid spam and identity manipulation, the receiver shall check the identity of the calling user against the address book. If the user is not in the address book, the alias information must then be used to provide more information about the calling user while clearly displaying in the User Interface (UI) that the identity is unchecked and it could be false. Otherwise the name of the contact in the address book shall be used instead.
当接收到请求时，RCS客户端设备应遵循第2.5.2.1节中解释的规则，并提取MSISDN或SIP URI。为了避免垃圾邮件和身份操纵，接收方应该根据地址簿检查主叫用户的身份。如果用户不在地址簿中，那么必须使用别名信息来提供关于主叫用户的更多信息，同时在用户界面（UI）中清楚地显示身份未被选中并且它可以是假的。否则，将使用通讯录中联系人的名称。

2.5 Addressing and identities / 寻址和身份