2.9 RCS and Access Technologies / RCS和接入技术

2.9.1 RCS and Cellular/EPC-integrated Wi-Fi Access / RCS和蜂窝/ EPC集成Wi-Fi接入

2.9.1.1 Access used by RCS in relation to VoLTE/VoWiFi / RCS使用的与VoLTE/VoWiFi相关的访问

A device providing both RCS and VoLTE/ViLTE or VoWiFi shall support the procedures described in [PRD-NG.102]. These procedures are dependent on the RCS VOLTE SINGLE REGISTRATION configuration parameter defined in section A.1.7.
提供RCS和VoLTE/ViLTE或VoWiFi的设备应支持[PRD-NG.102]中描述的过程。 这些过程取决于A.1.7节中定义的RCS VOLTE SINGLE REGISTRATION配置参数。

2.9.1.2 LTE Radio Capabilities / LTE无线电能力

Radio bearers, UE Discontinuous Reception (DRX) and Discontinuous Transmission (DTX) modes of operation, Radio Link Control (RLC) configurations, and Guaranteed Bitrate (GBR) and Non-Guaranteed Bitrate (NBGR) services and GBR Monitoring Function are all as specified in [PRD-IR.92] for devices enabled for VoLTE. None of this is applicable to other devices and access networks other than LTE.
无线电承载，UE不连续接收（DRX）和不连续传输（DTX）操作模式，无线电链路控制（RLC）配置以及保证比特率（GBR）和非保证比特率（NBGR）服务和GBR监视功能 对于启用VoLTE的设备，请参见[PRD-IR.92]。 这些都不适用于除LTE之外的其他设备和接入网络。

2.9.1.3 Bearer aspects / 承载方面

For all IMS traffic the following applies for an RCS device configured for VoLTE/VoWiFi:
对于所有IMS流量，以下适用于配置为VoLTE/VoWiFi的RCS设备：

• For LTE bearer management see section 4.3 of [PRD-IR.92] respectively.
  对于LTE承载管理，分别参见[PRD-IR.92]第4.3节。

For all RCS IMS traffic the following applies:
对于所有RCS IMS流量，适用以下内容：

• For a device enabled for VoLTE: LTE QCI (QoS class identifier) 8 and 9 shall be supported so that either may be used for MSRP traffic.
  对于启用VoLTE的设备：应支持LTE QCI（QoS类别标识符）8和9，以便可以用于MSRP业务。
• For a device using the IMS APN for RCS (see section 2.9.1.4): LTE QCI (QoS class identifier) 8 and 9 shall be supported so that either may be used for MSRP traffic.
  对于使用用于RCS的IMS APN的设备（参见第2.9.1.4节）：应支持LTE QCI（QoS类别标识符）8和9，以便可以用于MSRP业务。
• For other devices: no requirements.
  对于其他设备：无要求。

2.9.1.4 APN and roaming considerations / APN和漫游考虑

General technical guidelines on how roaming is handled for the RCS services shall follow [PRD-IR.65].
关于如何为RCS服务处理漫游的一般技术准则应遵循[PRD-IR.65]。

Guidance given for RCS and access technologies as documented in section 2.9 are applicable also in the roaming scenarios. Specific roaming considerations for the different RCS device types (as specified in section 2.2):
针对RCS和第2.9节中所述的访问技术提供的指导也适用于漫游场景。 不同RCS设备类型的特定漫游注意事项（如2.2节所述）如下：

• All services on a primary device enabled for VoLTE, shall follow the general rules as per [PRD-IR.88], APN usage as per [PRD-NG.102].
  启用VoLTE的主设备上的所有服务应遵循[PRD-IR.88]中的一般规则，[PRD-NG.102]中的APN使用。
• All services on a primary device enabled for VoWiFi shall follow the general rules as per [PRD-IR.61], APN usage as per [PRD-NG.102].
  启用VoWiFi的主设备上的所有服务应遵循[PRD-IR.61]的一般规则，按照[PRD-NG.102]的APN使用。
• Other devices: no specific requirements.
  其他设备：无具体要求。

The APN to be used to access the RCS services[20] depends on the capacity of the device and the network to support an IMS APN as per [PRD-IR.88], on the device configuration and on the client type (see section 2.2):
用于访问RCS服务[20]的APN取决于设备和网络按照[PRD-IR.88]支持IMS APN的能力，设备配置和客户端类型（参见 2.2节）如下：

• When the device is configured for VoLTE or VoWiFi, an embedded client shall use the APN indicated in [PRD-NG.102].
  当设备配置为VoLTE或VoWiFi时，嵌入式客户端应使用[PRD-NG.102]中指示的APN。

• For an embedded client on other devices, the behaviour shall depend on the setting of the RCS VOLTE SINGLE REGISTRATION (see section A.1.6) and NO MSRP SUPPORT configuration parameters (see section A.1.12):
  对于其他设备上的嵌入式客户端，行为将取决于RCS VOLTE SINGLE注册（请参见第A.1.6节）和NO MSRP SUPPORT配置参数（请参见第A.1.12节）的设置：
  

  NOTE: The RCS VOLTE SINGLE REGISTRATION configuration parameter is used in this case even if there is no VoLTE registration from the device because the required behaviour is similar.
  注：即使设备中没有VoLTE注册，也会使用RCS VOLTE SINGLE REGISTRATION配置参数，因为所需的行为类似。

  • The IMS APN shall be used to access the RCS services when the device is configured through the RCS VOLTE SINGLE REGISTRATION configuration parameter defined in section A.1.6 to use a single registration approach.
    当通过第A.1.6节中定义的RCS VOLTE SINGLE REGISTRATION配置参数配置设备以使用单一注册方法时，应使用IMS APN来访问RCS服务。
  • The Home Operator Services (HOS) APN shall be used to access the RCS services when the device is configured through the RCS VOLTE SINGLE REGISTRATION configuration parameter defined in section A.1.6 to use a dual registration approach.
    当设备通过第A.1.6节中定义的RCS VOLTE SINGLE REGISTRATION配置参数配置为使用双重注册方法时，家庭操作员服务（HOS）APN将用于访问RCS服务。

  • When roaming on a network that is listed in the NO MSRP SUPPORT configuration parameter (see section A.1.11), the client shall ignore the value of the RCS VOLTE SINGLE REGISTRATION configuration parameter when selecting the APN to use. The client shall use the HOS APN if obtained through client configuration; otherwise, the client shall use the Internet APN[21].
    当在NO MSRP SUPPORT配置参数（请参阅A.1.11）中列出的网络上漫游时，在选择要使用的APN时，客户端将忽略RCS VOLTE SINGLE REGISTRATION配置参数的值。 如果通过客户端配置获得，客户端将使用HOS APN; 否则，客户应使用Internet APN [21]。
    

    NOTE1: In the longer term, the visited network should indicate to the UE whether MSRP support is available. Until this is standardized, the NO MSRP SUPPORT configuration parameter is used.
    注1：从长远来看，被访网络应该向UE指示MSRP支持是否可用。 在标准化之前，将使用NON MSRP SUPPORT配置参数。

    NOTE2: When roaming on a network where the device cannot access a local IMS APN (e.g. no VoLTE roaming agreement is in place), a client configured to use the IMS APN will, by using the IMS APN, automatically access RCS through the home network’s IMS APN with the telephony service using the Circuit Switched network. If no IMS roaming agreement is in place, the visited network would degrade any requested QOS based on local configuration, as per normal procedures in the MME for any APN as specified in [PRD-IR.88]. The operator could optionally have a QoS data roaming agreement to ensure that QCI=5 for the IMS APN is allowed in the visited network and that either QCI=8 or QCI=9 for MSRP will be allowed on the IMS APN. If the appropriate QCI bearer cannot be set up for MSRP when on LTE access, MSRP traffic will be on the default QCI=5 bearer unless prevented by the terminal or network.
    注2：当在设备无法访问本地IMS APN（例如，没有VoLTE漫游协议已到位）的网络上漫游时，配置为使用IMS APN的客户端将通过使用IMS APN，通过家庭网络的 IMS APN与使用电路交换网络的电话服务。 如果没有IMS漫游协议到位，则如在[PRD-IR.88]中规定的任何APN的MME中的正常程序，被访问网络将基于本地配置降级任何所请求的QOS。 运营商可以可选地具有QoS数据漫游协定，以确保在访问网络中允许IMS APN的QCI = 5，并且在IMS APN上将允许用于MSRP的QCI = 8或QCI = 9。 如果在LTE接入时不能为MSRP建立适当的QCI承载，则MSRP业务将处于默认的QCI = 5承载，除非被终端或网络阻止。

  To support traffic from non-RCS applications (e.g. generic internet access) in this case the device and network shall support other APNs to be active simultaneously.
  为了支持来自非RCS应用（例如通用互联网接入）的流量，在这种情况下，设备和网络应该支持其他APN同时处于活动状态。
  For an embedded client, the APN to use for HTTP, XCAP and IMAP shall be the HOS APN as defined in [PRD-IR.88]. The HOS APN can be configured to be or by default be, the device’s generic data access APN (i.e. the internet APN21). The network should use the HOS APN when providing the RCS client with its configuration, in order to prevent unwanted data charging for client provisioning traffic.
  对于嵌入式客户端，用于HTTP，XCAP和IMAP的APN应为[PRD-IR.88]中定义的HOS APN。 HOS APN可以被配置为或者默认为设备的通用数据访问APN（即，因特网APN21）。 当为RCS客户端提供其配置时，网络应使用HOS APN，以防止对客户端设置流量进行不必要的数据计费。
  It is out of scope of this specification how the HOS APN is configured on the device.
  关于如何在设备上配置HOST SPN，超出本规范的范围。

• Downloadable clients shall use the internet APN.
  可下载的客户端应使用互联网APN。

[20] This section only covers the APN behaviour for RCS services. These settings shall not be taken into account for the usage of other APNs by non-RCS services.
[20] 本节仅介绍RCS服务的APN行为。 非RCS服务对其他APP的使用不应考虑这些设置。

[21] By internet APN, we understand the default APN configured by the Service Provider to provide Internet connectivity on the device
[21] 通过互联网APN，我们了解服务提供商配置的默认APN，以在设备上提供Internet连接

2.9.1.5 Data Off / 数据关闭

Users can switch cellular data usage off locally on their device. To allow the operator to offer IR 92 / IR 94 and RCS services to their customers even in these use cases, the data off switch shall have an operator configurable impact on the device connectivity. The service provider should ensure a good service experience if IP service usage is allowed although the data switch was set to off by the end user. The parameters to do so are introduced in section A.1.15 and are applicable for primary devices when RCS is not using the internet APN (see section 2.9.1.4).
用户可以在其设备上本地关闭蜂窝数据使用。 为了允许运营商即使在这些用例中向他们的客户提供IR 92 / IR 94和RCS服务，数据关闭交换机应该具有运营商对设备连接性的可配置影响。 如果允许IP服务使用，尽管最终用户将数据交换机设置为关闭，但服务提供商应确保良好的服务体验。 这样做的参数在A.1.15节中介绍，并且当RCS不使用因特网APN（见第2.9.1.4节）时适用于主设备。

When the cellular data switch is switched off and as a consequence a service is disabled according to the configuration in section A.1.15, the client shall not include the corresponding tags and service identifiers in the registration and capability exchange.
当蜂窝数据交换机关闭并且因此根据A.1.15节中的配置禁用服务时，客户端不应在注册和能力交换中包括相应的标签和服务标识符。

When according to the configuration defined in section A.1.15 all RCS services being relevant for capability discovery are disabled when the cellular data switch is switched off (i.e. all of RCS MESSAGING DATA OFF, FILE TRANSFER DATA OFF, CONTENT SHARE DATA OFF, PRE AND POST CALL DATA OFF and EXTENSIONS DATA OFF are set to 0 or are set to 2 and the device is connected to a cellular network other than the HPLMN or the parameters are not relevant because the corresponding service is not available on cellular networks), a client shall also disable the capability exchange when needing to use cellular networks to provide those services and cellular data is switched off. In those circumstances, a client shall neither send capability exchange requests nor respond to such requests (allowing them to time-out in the network).
当根据A.1.15节中定义的配置，当蜂窝数据交换机关闭时（即所有RCS消息数据关闭，文件传输数据关闭，内容共享数据关闭，预先和 呼叫数据关闭和扩展数据关闭设置为0或设置为2，并且设备连接到除了HPLMN之外的蜂窝网络或者参数不相关，因为相应的服务在蜂窝网络上不可用），客户端 当需要使用蜂窝网络来提供这些服务并且蜂窝数据被关闭时，也将禁用能力交换。 在这些情况下，客户端既不发送能力交换请求也不响应这些请求（允许它们在网络中超时）。

When according to the configuration defined in section A.1.15, all IMS services are disabled when the cellular data switch is switched off (i.e. all of RCS MESSAGING DATA OFF, FILE TRANSFER DATA OFF, SMSOIP DATA OFF, CONTENT SHARE DATA OFF, PRE AND POST CALL DATA OFF, VOLTE DATA OFF, IP VIDEO CALL DATA OFF and EXTENSIONS DATA OFF are set to 0 or are set to 2 and the device is connected to a cellular network other than the HPLMN) or are not relevant because the corresponding service is not available on cellular networks and provided the client does not offer any other IMS services beyond the scope of VoLTE and RCS, a client shall not register in the IMS when needing to use cellular networks to provide those services and cellular data is switched off. In this case, if the device is in LTE coverage, the device shall either connect to 2G/3G network access only or in LTE keep a data connection over which no data is sent if no other data connection is required/available for the Circuit Switched Fall Back and SMS over SGs to happen.
当根据A.1.15节中定义的配置，当蜂窝数据交换机关闭时（即所有RCS MESSAGING DATA OFF, FILE TRANSFER DATA OFF, SMSOIP DATA OFF, CONTENT SHARE DATA OFF, PRE AND POST CALL DATA OFF, VOLTE DATA OFF, IP VIDEO CALL DATA OFF 和 EXTENSIONS DATA OFF设置为0或设置为2，并且设备连接到除HPLMN之外的蜂窝网络）或不相关，因为相应的服务是在蜂窝网络上不可用，并且只要客户端不提供超出VoLTE和RCS范围的任何其他IMS服务，当需要使用蜂窝网络来提供那些服务并且蜂窝数据被关闭时，客户端不应当在IMS中注册。在这种情况下，如果设备在LTE覆盖范围内，则设备将仅连接到2G / 3G网络接入，或者在LTE中保持没有数据发送的数据连接，如果没有其他数据连接需要/可用于电路交换回退和短信通过SG发生。

For services using non IMS protocols having no data connection at the time of disabling, no additional actions are required by the client. If disabled by Data off configuration the service will not be available at the time of invocation.
对于使用在禁用时没有数据连接的非IMS协议的服务，客户端不需要其他操作。 如果通过数据关闭配置禁用，则在调用时服务将不可用。

For services using non IMS protocols and having a data connection active at the time of disabling, the ongoing session or transaction shall be terminated.
对于使用非IMS协议并且在禁用时具有活动的数据连接的服务，正在进行的会话或事务将被终止。

2.9.1.6 Summary of conditions and parameters that control the access network used / 控制接入网络使用的条件和参数的摘要

The combination of the switches, configuration parameters and coverage conditions introduced to control the connection through which the service is delivered leads to the behaviour described in Table 26:
引入的用于控制递送服务的连接的交换机，配置参数和覆盖条件的组合导致表26中描述的行为：

Table 26: APN configuration proposal for data traffic and roaming / 表26：数据流量和漫游的APN配置建议

[22] See Error! Reference source not found.
[22] 请参阅错误！ 找不到参考源。

[23] Dual registration is used when the RCS VoLTE SINGLE REGISTRATION configuration parameter is configured to 0, when RCS VoLTE SINGLE REGISTRATION configuration parameter is configured to 2 and the device is roaming and when roaming on a visited network that is listed in the NO MSRP SUPPORT configuration parameter. Otherwise single registration is used.
[23] 当RCS VoLTE SINGLE REGISTRATION配置参数配置为0时，当RCS VoLTE SINGLE REGISTRATION配置参数配置为2且设备正在漫游时以及在NO MSRP SUPPORT配置参数中列出的访问网络上漫游时，将使用双重注册 。 否则使用单次注册。

[24] i.e. at least one of RCS MESSAGING DATA OFF, FILE TRANSFER DATA OFF, CONTENT SHARE DATA OFF, PRE AND POST CALL DATA OFF, EXTENSIONS DATA OFF as defined in A.1.15 is set to 1 or it is set to 2 and the device is attached to the HPLMN or IP VIDEO CALL DATA OFF defined in A.1.15 is set to 1 or it is set to 2 and the device is attached to the HPLMN on a device that is not enabled for VoLTE.
[24] 即，如A.1.15中定义的RCS消息数据关闭，文件传输数据关闭，内容共享数据关闭，PRE和POST呼叫数据关闭，扩展数据关闭中的至少一个被设置为1或设置为2， 连接到HPLMN或IP A.1.15中定义的IP视频呼叫数据关闭设置为1或设置为2，并且设备连接到未启用VoLTE的设备上的HPLMN。

[25] i.e. for traffic related to Standalone Messaging, 1-to-1 Chat, Group Chat, File Transfer, Video Share and Image Share, RCS IP Voice Call, RCS IP Video Call and Extension to Extension traffic as defined in section 3.2, 3.3, 3.4, 3.5, 3.6, 3.8, 3.9 and 3.12 respectively. VoLTE, ViLTE, SMSover IP and MMS always use the cellular network.
[25] 即，如第3.2，3.3，3.4，3.5，3.6，3.8，3.9和3.12节分别定义的，对于独立消息，1对1聊天，群聊，文件传输，视频共享和图像共享，RCS IP语音呼叫，RCS IP视频呼叫和分机到分机流量相关的流量 ，VoLTE，ViLTE，SMSover IP和MMS总是使用蜂窝网络。

[26] Case assuming VoLTE remains switched on when data is off. If not, available cellular coverage is assumed to be CS.
[26] 假定VoLTE在数据关闭时保持打开状态。 如果不是，则假定可用的蜂窝覆盖是CS。

2.9.2 Other access networks / 其他接入网络

2.9.2.1 Overview / 概述

In addition to the cellular PS access networks described in sections 2.9.1.4 and 2.9.1, the RCS framework and services can be used over any IP access over which the Service Provider’s IMS core and application servers can be reached, provided that it offers sufficient bandwidth and an acceptable latency. Section 2.7 provides a guideline for which services can be used when connected through different types of access networks including broadband access.
除了2.9.1.4节和2.9.1节中描述的蜂窝PS接入网络之外，RCS框架和服务可以在可以到达服务提供商的IMS核心和应用服务器的任何IP接入上使用，只要它提供足够的 带宽和可接受的延迟。 第2.7节提供了在通过包括宽带接入的不同类型的接入网络连接时可以使用哪些服务的准则。

These other networks can be both trusted and untrusted networks. “Trusted” means that HPLMN considers the access network trusted independently of the specific mechanism for authentication and encryption of end-user traffic that the access network implements. The access network is integrated into the Service Provider core infrastructure in such a way that the whole path from a mobile to services is considered secure by the HPLMN and under the control of respective Service Providers. Fixed access networks including ADSL (Asymmetric Digital Subscriber Line), cable modem access, FTTH (Fibre To The Home) and WLAN networks could therefore be considered as a “Trusted” network by the HPLMN if they are entirely Service Provider controlled. The same holds for clients using a cellular PS connection as broadband access.
这些其他网络可以是可信和不可信网络。 “可信”意味着HPLMN独立于接入网络实现的用于终端用户流量的认证和加密的特定机制而认为接入网络是可信的。 接入网络以这样的方式被集成到服务提供商核心基础设施中，使得从移动设备到服务的整个路径被HPLMN认为是安全的并且在相应的服务提供商的控制下。 因此，如果它们完全是服务提供商控制的，则包括ADSL（非对称数字用户线路），电缆调制解调器接入，FTTH（光纤到户）和WLAN网络的固定接入网络可以被HPLMN认为是“可信”网络。 这同样适用于使用蜂窝PS连接作为宽带接入的客户端。

Untrusted broadband networks, however, are at least partly controlled by some 3rd party and may, therefore, require more elaborate security measures to guarantee privacy and authenticity of the signalling and media traffic. As in this case, the network does not provide the support for functionality such as encryption natively, it needs to be added to it before that particular network can be used to access the IMS core system. If the HPLMN considers direct access from a broadband network such as public Wi-Fi hotspots to the IMS core system untrusted, then in order to avoid security risks such as Denial of Service attacks towards Service Provider core components there is a requirement for additional secure access mechanisms to be deployed.
然而，不可信的宽带网络至少部分地由某些第三方控制，因此可能需要更复杂的安全措施以保证信令和媒体业务的隐私和真实性。 在这种情况下，网络不提供对诸如本地加密的功能的支持，所以在该特定网络可以用于接入IMS核心系统之前，需要将其添加到网络。 如果HPLMN认为从诸如公共Wi-Fi热点的宽带网络到不可信的IMS核心系统的直接访问，则为了避免诸如对服务提供者核心组件的拒绝服务攻击的安全风险，需要附加的安全访问 机制。

Many such secure access mechanisms are possible and can either be xSIM based or use other types of credentials. For commercial deployments, the choice will be dependent on the type of client and on the environment. For example, the same type of client could only use PS Mobile Broadband Access, access over the internet or only over a fixed ADSL line / FTTH access which may require using different mechanisms for each case. Therefore given that this choice will end up being specific to each deployment, it is not considered in scope of RCS to specify an exhaustive list of supported access mechanisms.
许多这样的安全访问机制是可能的，并且可以是基于xSIM或使用其他类型的凭证。 对于商业部署，选择将取决于客户端的类型和环境。 例如，相同类型的客户端只能使用PS移动宽带接入，通过互联网或仅通过固定的ADSL线路/ FTTH接入，这可能需要对每种情况使用不同的机制。 因此，考虑到这种选择将最终针对每个部署，在RCS的范围内不考虑指定支持的接入机制的详尽列表。

As described in section 2.8 both trusted and untrusted networks need to be able to provide access and authentication over NAT. This must be taken into account for example when xSIM based access, IPSec or other fixed access authentication mechanisms are used.
如第2.8节所述，可信和不可信网络需要能够通过NAT提供访问和认证。 例如，当使用基于xSIM的访问，IPSec或其他固定访问认证机制时，必须考虑这一点。

This support for access over non-cellular networks can be used in two ways:
这种对通过非蜂窝网络接入的支持可以以两种方式使用：

1. As an offloading capability for the cellular network This will be controlled by the device itself:
   作为蜂窝网络的卸载能力这将由设备本身控制：
   • When a device is enabled for VoLTE/VoWiFi (see section 2.9.1.1), it is expected that the device either remains on LTE access for as long as it is available or switches to EPC-integrated Wi-Fi (see Table 26).
     当设备启用VoLTE / VoWiFi（参见第2.9.1.1节）时，预期设备在可用时保持LTE接入或切换到EPC集成Wi-Fi（参见表26）。
   • When the voice service is provided via CS access, it is up to the device when and whether to move to non-cellular (e.g. non EPC-integrated Wi-Fi) access. If a device moves to a non-cellular network, it is expected that the device first de- registers in IMS from the cellular network, and then registers in IMS in the non- cellular network, or vice versa when moving in the other direction.
     当经由CS接入提供语音服务时，由设备决定是否移动到非蜂窝（例如，非EPC集成Wi-Fi）接入。 如果设备移动到非蜂窝网络，则预期该设备首先在IMS中从蜂窝网络解除注册，然后在非蜂窝网络中在IMS中注册，或者反之亦然，当在另一方向上移动时。
2. As a means of access for dedicated broadband clients using the identity of the mobile device
   作为使用移动设备的身份的专用宽带客户端的接入手段
   This can be either as a standalone client when there is no mobile device using that same identity or as secondary client to a mobile device sharing the same identity (see chapter 2.5). In the latter case the user will have multiple devices sharing the same identity. Chapter 2.11 provides further details on how this can be realised.
   当没有移动设备使用相同的身份时，这可以作为独立的客户端，或者作为具有相同身份的移动设备的辅助客户端（见第2.5章）。 在后一种情况下，用户将具有共享相同身份的多个设备。 第2.11章提供了如何实现这一点的进一步细节。
   These differences are further detailed in section 2.9.2.2.
   这些差异在第2.9.2.2节中进一步详细说明。

2.9.2.2 Dedicated RCS clients on Broadband Access / 宽带接入上的专用RCS客户端

Next to clients using mobile access, RCS also supports dedicated clients using broadband access. Such a client can operate in two significantly different modes:
除了使用移动接入的客户端，RCS还支持使用宽带接入的专用客户端。 这样的客户端可以以两种显着不同的模式操作：

1. As a secondary client, adding performance (such as larger keyboard, a screen with higher resolution and so on) to the primary mobile client with RCS functionality. Such a secondary client is designed with user experience aspects, storage accessibility and so on, but is not designed to act as a primary telephony device. In this case the primary client retains aspects a user would associate with their device, for example regulatory functions, quality of service and full access to the telephony functions.
   作为辅助客户端，向具有RCS功能的主要移动客户端添加性能（例如较大的键盘，具有较高分辨率的屏幕等）。 这样的辅助客户端被设计为具有用户体验方面，存储可访问性等，但是不被设计为充当主电话设备。 在这种情况下，主客户端保留用户将与他们的设备相关联的方面，例如监管功能，服务质量和对电话功能的完全访问。
   
   Figure 18: RCS Broadband Access client used as a secondary client / 图18：用作辅助客户端的RCS宽带接入客户端
   

   NOTE: Other combinations of multiple devices, such as support of multiple mobile clients, are out of scope for RCS. However, this does not restrict a Service Provider to deploy proprietary solutions to achieve this.
   注意：多个设备的其他组合（例如多个移动客户端的支持）不在RCS的范围内。 然而，这并不限制服务提供商部署专有解决方案来实现这一点。

2. As a primary client, replacing the user’s mobile client. A primary client has to meet all regulatory requirements (emergency calling, lawful intercept, etc.) and perform to meet the traditionally expected telephony functionality and demonstrate the reliability, performance and quality of service of a primary device. The precondition for its use is that basic telephony services are already available in the Broadband Access network. For these services, the local regulations are already fulfilled.
   作为主要客户端，替换用户的移动客户端。 主要客户端必须满足所有监管要求（紧急呼叫，合法拦截等），并执行以满足传统预期的电话功能，并展示主设备的可靠性，性能和服务质量。 其使用的前提是宽带接入网络中已经存在基本电话服务。 对于这些服务，地方法规已经实现。
   
   Figure 19: RCS Broadband Access client used as a primary client / 图19：用作主客户端的RCS宽带接入客户端