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5.2.1A.3 Application detection with PFD

The detection information for a given application may be provisioned by the CP function to the UP function via PFD management procedure. See subclause 6.2.5.

给定应用的检测信息可由CP功能经由PFD管理过程提供给UP功能。

The PFDE (PFD Enhancement) feature may be optionally supported by the CP function and UP function. When the feature is supported in both the CP function and UP function, the CP function may provision a PFD Contents IE including a property (i.e. either flow description, or URL or Domain Name/Domain Name Protocol) with multiple values.

PFDE（PFD Enhancement）功能可选择性地由CP功能和UP功能支持。当CP功能和UP功能都支持该功能时，CP功能可以提供PFD Contents IE，包括具有多个值的属性（即流描述、URL或Domain Name/Domain Name Protocol）。

NOTE 1: It is assumed, when the PFDE feature is not supported, a PFD Contents can only include a property with one value.

注1：假设不支持PFDE功能时，PFD Contents只能包含一个值的属性。

When the UP function attempts to detect the traffic pertaining to an application by using the application's PFDs (see subclause 7.4.3.1 and 8.2.39), the UP function shall consider:

当UP功能尝试使用应用程序的PFD检测与应用程序有关的流量时，UP功能应考虑：

- the application is detected if the incoming traffic matches one of PFD Contents;

-如果入向流量与PFD Contents之一匹配，则检测应用程序；

- the PFD Contents is matched if the incoming traffic matches at least one value of a property in the same PFD Contents IE.

-如果入向流量与同一PFD Contents IE中的属性的至少一个值匹配，则PFD Contents匹配。

NOTE 2: Interpretation of the Custom PFD Content is implementation specific.

注2：Custom PFD Content的解释是特定于实现的。

5.2.2.2.1 General

If the UP function indicated support of the Quota Action feature in the UP Function Features IE, when the CP function provisions a Volume Quota or Time Quota in a URR, the CP function may also provision the "FAR ID for Quota Action" IE identifying the substitute FAR the UP function shall apply, for the traffic associated identified by the PDR to this URRwhich the URR is associated, when exhausting any of these quotas. This FAR may require the UP function to drop the packets or redirect the traffic towards a redirect destination as specified in subclause 5.4.7.

当耗尽任何这些配额时，识别UP功能的Action IE应适用于与URR相关的PDR所识别的流量。该FAR可能要求UP功能丢弃数据包或将流量重定向至重定向目的地。

NOTE 7: A PDR can be associated with multiple URRs. If one of these URRs requires the UP function to drop the user data packets, e.g. when the Quota has been exhausted, the other URRs associated to the PDR need also to stop their measurements, except for URRs including the Measurement Information with the 'Measurement Before QoS Enforcement' flag set to 1.

注7：PDR可与多个URR关联。如果这些URR中的一个需要UP功能来丢弃用户数据包，例如，当Quota已用完时，与PDR相关联的其他URR也需要停止其测量，但包括“Measurement Before QoS Enforcement”标志设置为1的Measurement Information的URR除外。

5.4.2 Service Detection and Bearer BindingBearer/QoS Flow Binding

Service detection refers to the process that identifies the packets belonging to a service data flow or application. See For EPC, see subclauses 6.2.2.2 and 6.8.1 of 3GPP TS 23.203 [7].. For 5GC, see subclause 6.2.2.2 of 3GPP TS 23.503 [44].

Bearer For EPC, bearer binding is the procedure that associates service data flow(s) to an IP-CAN bearer deemed to transport the service data flow. UL bearer binding verification refers to the process of discarding uplink packets due to no matching service data flow template for the uplink direction. See subclauses 6.1.1.4 and 6.2.2.2 of 3GPP TS 23.203 [7]..

For 5GC, QoS flow binding is the procedure that associates service data flow(s) to a QoS flow deemed to transport the service data flow. UL QoS flow binding verification refers to the process of discarding uplink packets due to no matching QoS flow for the uplink direction. See subclause 6.1.3.2.4 of 3GPP TS 23.503 [44] and subclause 5.7.1.7 of 3GPP TS 23.501 [28].

对于5GC，QoS流绑定是将业务数据流与被视为传输业务数据流的QoS流相关联的过程。UL QoS流绑定验证是指由于上行链路方向没有匹配的QoS流而丢弃上行链路分组的过程。

Service detection is controlled over the Sxa, Sxb Sxb, Sxc and Sxc N4 reference points by configuring Packet Detection Information in PDRs to match the intended service data flows or application.

The For EPC, the mapping of DL traffic to bearers is achieved by configuring and associating FARs to the downlink PDRs, with FARs set to forward the packets to the appropriate downstream bearers (S5/S8 or S1/S12/S4/Iu).

Uplink For 5GC, the mapping of DL traffic to QoS flows is achieved by configuring QERs with QFI(s) for the QoS flow marking and associating FARs to the downlink PDRs, with FARs set to forward the packets to the appropriate downstream GTP-U tunnel (N9 or N3).

对于5GC，通过将QER配置为QoS流标记的QFI，并将FAR与下行链路PDR关联，将FAR设置为将数据包转发到适当的下游GTP-U隧道（N9或N3），实现DL业务到QoS流的映射。

For EPC, uplink bearer binding verification is achieved by configuring Packet Detection Information in uplink PDRs containing the local F-TEID of the uplink bearer, the UE IP address (source IP address to match for the incoming packet), and the SDF filter(s) or the Application ID. As a result, uplink packets received on the uplink bearer but that do not match the SDF filter(s) or Application detection filter associated to the uplink PDRs are discarded.

For 5GC, uplink QoS flow binding verification (see subclause 5.7.1.7 of 3GPP TS 23.501 [28]) is achieved by configuring Packet Detection Information in uplink PDRs containing the local F-TEID of the uplink PDU session, the UE IP address (source IP address to match for the incoming packet), the QFI of the QoS flow and the SDF filter(s) or the Application ID. As a result, uplink packets received on the uplink PDU session but that do not match the SDF filter(s) or Application detection filter and QFI associated to the uplink PDRs are discarded.

对于5GC，上行链路QoS流绑定验证是通过在上行链路PDR中配置包含上行链路PDU会话的本地F-TEID、UE IP地址（与入向数据包匹配的源IP地址）、QoS流的QFI和SDF过滤器的Packet Detection Information来实现的或Application ID。因此，在上行链路PDU会话上接收的上行链路数据包（但与SDF筛选器或Application检测过滤器不匹配）和与上行链路PDR相关联的QFI被丢弃。

NOTE 4: The UPF can be provisioned with a PDR (with low precedence) which contains the CN tunnel info, QFI and filter information that can detect any unwanted/unauthorized traffic with this QFI so that such traffic can be dropped with or without being counted before.

注4：UPF可配备PDR（低优先级），该PDR包含CN隧道信息、QFI和过滤器信息，可使用该QFI检测任何不需要的/未经授权的流量，以便此类流量可在之前计数或不计数的情况下丢弃。

5.4.6 Usage Monitoring

Usage Monitoring Control refers to the process of monitoring the user plane traffic in the PGW-U or U, TDF-U or UPF for the accumulated usage of network resources per:

- individual or group of service data flows;

- individual or group of applications;

- PDU session, possibly excluding an individual SDF or a group of service data flow(s) (for 5GC);

-PDU会话，可能不包括单个SDF或一组业务数据流（用于5GC）；

- IP-CAN session, possibly excluding an individual SDF or a group of service data flow(s) (for EPC), and/or

- TDF session, possibly excluding an individual application or a group of application(s) (for EPC).

See subclauses For EPC, see subclauses 4.4, 6.2.2.3 and 6.6 of 3GPP TS 23.203 [7] and subclauses 4.5.16, 4.5.17, 4b.5.6, 4b.5.7 of 3GPP TS 29.212 [8].

For 5GC, see subclauses 4.3.4 and 6.2.2.3 of 3GPP TS 23.503 [44] and subclauses 4.2.2.10, 4.2.3.11, 4.2.4.10, 4.2.6.2.5, 4.2.6.5.3 of 3GPP TS 29.512 [41].

Usage Monitoring Control is supported over the Sxb Sxb, Sxc and Sxc N4 reference points by activating in the UP function the reporting of usage information towards the CP function, as specified in subclauses 5.3 and 7.8.4 of 3GPP TS 23.214 [2] and in subclause 5.8.2.6.2 of 3GPP TS 23.501 [28]. 

5.4.7 Traffic Redirection

Traffic Redirection refers to the process of redirecting uplink application traffic, in a PGW PGW, TDF or TDFUPF, towards a redirect destination, e.g. redirect some HTTP flows to a service provisioning page. See For EPC, see subclause 6.1.13 of 3GPP TS 23.203 [7] and subclauses 4.5.2.6 and 4b.5.1.4 of 3GPP TS 29.212 [8].. For 5GC, see subclause 6.1.3.12 of 3GPP TS 23.503 [44] and subclause 4.2.6.2.4 of 3GPP TS 29.512 [46].

The redirect destination may be provided by the PCRF PCRF/PCF or be preconfigured in the CP function or in the UP function.

The For EPC, the traffic redirection may be enforced in the CP function or in the UP function. For 5GC, the traffic redirection may be enforced in the UP function only. If the traffic that the UP function can support may be subject to traffic redirection, traffic redirection enforcement in the UP function shall be supported by the UP function. The UP function reports to the CP function whether it supports traffic redirection enforcement in the UP function via the UP Function Features IE (see subclause 8.2.25).

对于EPC，可以在CP功能或UP功能中实施流量重定向。对于5GC，只能在UP功能中实施流量重定向。如果UP功能可以支持的流量可能会进行流量重定向，则UP功能应支持UP功能中的流量重定向实施。UP功能通过UP Function Features IE向CP功能报告其是否支持UP功能中的流量重定向实施。

5.4.10 Charging

The For EPC, the charging requirements for online and offline charging in the PS domain specified in 3GPP TS 32.251 [17] shall be preserved with a split SGW, PGW and TDF architecture.

For 5GC, the charging requirements for online and offline charging in the 5G data connectivity domain are specified in 3GPP TS 32.255 [45].

对于5GC，3GPP TS 32.255[45]中规定了5G数据连接域中在线和离线充电的计费要求。

Charging is supported by the CP function by activating in the UP function the measurement and reporting of the accumulated usage of network resources per:

- for EPC:

- IP-CAN bearer, for an SGW;

- IP-CAN bearer, IP-CAN session and/or individual or group of service data flows, for a PGW;

- TDF session and/or individual or group of applications, for a TDF;

- for 5GC:

- PDU session and/or individual or group of service data flows, for an SMF

- QoS Flow, for an SMF.

5.4.11 (Un)solicited Application Reporting

Editor's Note: (Un)solicited Application Reporting in 5GC is FFS.

 (UnFor EPC, (un)solicited Application Reporting refers to the process of reporting the start or stop of applications by the TDF or PCEF. See 3GPP TS 23.203 [3] and 3GPP TS 29.212 [8].

For 5GC, solicited Application Reporting refers to the process of reporting the start or stop of applications by the SMF to the PCF. See 3GPP TS 23.503 [44] and 3GPP TS 29.512 [41]. Unsolicited application reporting is not applicable for 5GC.

对于5GC，请求申请报告是指SMF向PCF报告申请开始或停止的过程。未经请求的申请报告不适用于5GC。

5.4.13 Transport Level Marking 

For EPC, transport level marking is performed on a per EPS bearer basis in the SGW and PGW. Transport level marking refers to the process of marking traffic with a DSCP value based on the locally configured mapping from the QCI and optionally ARPthe ARP priority level.

对于EPC，在SGW和PGW中按照每个EPS承载人进行传输级别标记。传输级别标记是指根据QCI本地配置的映射和可选的ARP优先级，使用DSCP值标记流量的过程。

For 5GC, transport level marking is performed on a per QoS flow basis. Transport level marking refers to the process of marking traffic at the UPF with a DSCP value based on the mapping from the 5QI 5QI, the Priority Level (if explicitly signalled) and optionally the ARP priority level configured at the SMF.

对于5GC，在每个QoS流的基础上执行传输级别标记。传输级别标记是指根据5QI的映射、Priority Level（如果明确发出信号）和可选的在SMF配置的ARP优先级，使用DSCP值在UPF标记流量的过程。

5.7.3 Lawful Interception in 5GC

Requirements for support of Lawful Interception with SMF and UPF are specified in subclauses 6.2.3 of 3GPP TS 33.127 [47].

3GPP TS 33.127[47]第6.2.3款规定了支持SMF和UPF Lawful Interception的要求。

User plane packets shall be forwarded from the UPF to the MDF3 by encapsulating the user plane packets using GTP-U encapsulation (see 3GPP TS 29.281 [3]).

应通过使用GTP-U封装封装用户平面分组，将用户平面分组从UPF转发到MDF3。

The SMF shall instruct the UPF to duplicate the packets to be intercepted and to forward them to the MDF3 as specified in subclause 5.2.3.

SMF应指示UPF复制要监听的数据包，并按照第5.2.3款的规定将其转发给MDF3。

For forwarding data from the UPF to the MDF3, the SMF shall set the DUPL flag in the Apply Action and set the Duplicating Parameters in the FAR, associated to the PDRs of the traffic to be intercepted, with the Destination Interface "LI Function" and set to perform GTP-U encapsulation and to forward the packets to a GTP-u F-TEID uniquely assigned in the MDF3 for the traffic to be intercepted. The MDF3 shall then identify the intercepted traffic by the F-TEID in the header of the encapsulating GTP-U packet. The SUPI, PEI and/or GPSI may be provided in the user ID to the UPF.

为了将数据从UPF转发到MDF3，SMF应在Apply Action中设置DUPL标志，并在FAR中设置Duplicating Parameters，该参数与要监听的流量的PDR相关，Destination Interface为“LI Function”以及设置为执行GTP-U封装，并将分组转发到在MDF3中为要监听的流量唯一分配的GTP-U F-TEID。然后，MDF3应在封装GTP-U数据包的报头中识别F-TEID监听的流量。SUPI、PEI和/或GPSI可以在用户ID中提供给UPF。

5.8.1 General

An PFCP Association shall be set up between the CP function and the UP function prior to establishing PFCP sessions on that UP function. Only one PFCP association shall be setup between a given pair of CP and UP functions, even if the CP and/or UP function exposes multiple IP addresses.

在建立关于UP功能的PFCP会话之前，应在CP功能和UP功能之间建立PFCP Association。即使CP和/或UP功能公开多个IP地址，在给定的CP和UP功能对之间也只能建立一个PFCP偶联。

The CP function and the UP function shall support the PFCP Association Setup procedure initiated by the CP function (see subclause 6.2.6.2). The CP function and the UP function may additionally support the PFCP Association Setup procedure initiated by the UP function (see subclause 6.2.6.3).

A CP function may have PFCP Associations set up with multiple UP functions. A UP function may have PFCP Associations set up with multiple CP functions.

A CP function or a UP function shall be identified by a unique Node ID. A Node ID may be set to an FQDN or an IP address (see subclause 8.2.38).

CP功能或UP功能应由唯一的Node ID标识。Node ID可设置为FQDN或IP地址。

Prior to establishing an PFCP Association, the function responsible for establishing the PFCP Association (e.g. CP function) shall look up a peer function (e.g. UP function), e.g using DNS procedures (see 3GPP TS 29.303 [25]), NRF procedures (see 3GPP TS 29.510 [43]) or local configuration. If the peer function is found to support multiple IP addresses (in the look up information), one of these addresses (any one) shall be used as destination IP address to send the PFCP Association Setup Request. Once the PFCP Association is established, any of the IP addresses of the peer function (found during the look-up) may then be used to send subsequent PFCP node related messages and PFCP session establishment requests for that PFCP Association.  

在建立PFCP Association之前，负责建立PFCP偶联的功能（例如CP功能）应查找对等功能（例如UP功能），例如使用DNS程序、NRF程序或本地配置。如果发现对等功能支持多个IP地址（在查找信息中），则其中一个地址（任意一个）应用作发送PFCP Association Setup Request的目标IP地址。一旦建立PFCP Association，对等功能的任何IP地址（在查找期间找到）随后可用于发送该PFCP Association的后续PFCP节点相关消息和PFCP会话建立请求。

NOTE 1: The look up information (e.g. in DNS, NRF or local configuration of the function responsible for establishing the PFCP association) needs to be configured consistently with the addressing information of the peer function. If a FQDN is configured to identify a function in DNS or NRF, then the Node ID of that function included in PFCP messages need to be set to the same FQDN. For instance, if the CP function is responsible for establishing the PFCP association, a UP function that exposes multiple IP addresses (for PFCP node related messages and PFCP session establishment requests) needs to be configured in the look up information as one (single) UP function that is associated to multiple IP addresses.

注1：查找信息（例如，在负责建立PFCP偶联的功能的DNS、NRF或本地配置中）需要与对等功能的寻址信息一致地配置。如果FQDN配置为标识DNS或NRF中的功能，则PFCP消息中包含的该功能的Node ID需要设置为相同的FQDN。例如，如果CP功能负责建立PFCP偶联，则需要在查找信息中将公开多个IP地址（用于PFCP节点相关消息和PFCP会话建立请求）的UP功能配置为与多个IP地址关联的一个（单个）UP功能。

NOTE 2: PFCP session related messages for sessions that are already established are sent to the IP address received in the F-SEID allocated by the peer function. This IP address need not be configured in the look up information. See subclause 4.3.2 and 4.3.3.

注2：已建立会话的PFCP会话相关消息发送至对等功能分配的F-SEID中接收的IP地址。不需要在查找信息中配置此IP地址。

5.11 User plane inactivity detection and reporting

Subclause 5.4.4.1 of 3GPP TS 23.401 [14] requires the PGW to initiate the release of an inactive emergency PDN connection.

Subclause 4.3.7 and 4.3.2.2.2 of 3GPP TS 23.502 [29] requires the SMF to be able to initiate the deactivation of the UP connection of an existing PDU session without user plane activity for a given inactivity period, except for the H-SMF for the home routed roaming scenario or except for an always-on PDU session as described in subclause 5.6.8 of 3GPP TS 23.501 [28].

3GPP TS 23.502[29]的子条款4.3.7和4.3.2.2.2要求SMF能够在给定的非活动期内，在没有用户平面活动的情况下启动现有PDU会话的上行连接的停用，除了归属路由漫游场景的H-SMF或3GPP TS 23.501[28]子条款5.6.8中描述的始终在线PDU会话之外。

5.13.1 General

The SMF may also request a UPF, acting as a PDU session anchor, to:

- redirect ARP Address Resolution Protocol (ARP) (see IETF RFC 826 [32]) or IPv6 Neighbour Solicitation traffic (see IETF RFC 4861 [33]) to the SMF as specified in subclause 5.13.2, or to respond to perform ARP proxying or IPv6 Neighbour Advertisement proxying Solicitation based on the local cache information as specified in subclause 5.13.3;

-将Address Resolution Protocol（ARP）或IPv6 Neighbour Solicitaion流量重定向至SMF，或根据第5.13.3款规定的本地缓存信息响应ARP或IPv6邻居请求；

- report the MAC (Ethernet) addresses used as source address of frames sent UL by the UE, as specified in subclause 5.13.5.

For a PFCP session set up for an Ethernet PDU session, the UPF shall:

- detect Ethernet traffic, based on Ethernet Packet Filter(s) provisioned in PDR(s) by the SMF, and process the Ethernet traffic as instructed in the FAR, QER(s) and URR(s) associated to the PDR(s);

- forward ARP Address Resolution Protocol (see IETF RFC 826 [32]) or IPv6 Neighbour Solicitation messages (see IETF RFC 4861 [33]) to the SMF, as specified in subclause 5.13.2, if so required by the SMF.

-如SMF要求，按照第5.13.2款的规定，将Address Resolution Protocol或IPv6 Neighbour Solicitation消息转发至SMF。

- perform ARP proxying respond to Address Resolution Protocol (see IETF RFC 826 [32]) or IPv6 Neighbour Advertisement proxyingSolicitation (see IETF RFC 4861 [33]) based on the local cache information, as specified in subclause 5.13.3, if so required by the SMF;

-如果SMF有要求，根据第5.13.3款规定的本地缓存信息，响应地址解析协议（见IETF RFC 826[32]）或IPv6邻居请求（见IETF RFC 4861[33]）；

5.13.2 ARP Address Resolution Protocol or IPv6 Neighbour Advertisement Proxying in Solicitation Response by SMF

If the SMF requests the UPF to forward all ARP Address Resolution Protocol (ARP) (see IETF RFC 826 [32]) or IPv6 Neighbour Solicitation (see IETF RFC 4861 [33]) traffic to the SMF to do respond to the ARP or IPv6 Neighbour Advertisement proxying Solicitation based on the local cache information for Ethernet PDU sessions, the SMF shall provision a PDR in the UPF with:

如果SMF请求UPF将所有Address Resolution Protocol（ARP）或IPv6 Neighbour Solicitaion流量转发给SMF，以基于Ethernet PDU会话的本地缓存信息响应ARP或IPv6 Neighbour Solicitaion，SMF应在UPF中提供PDR，包括：

- an Ethernet Packet Filter containing EtherType 2054 (hexadecimal 0x0806) and associate the PDR with a FAR, for forwarding ARP traffic to the SMF; and/or

- a PDI containing an application ID such that the identified application ID matches against EtherType 34525 (hexadecimal 0x86DD), IPv6 Next Header type as 58 and ICMP Field Type as 135 and associate the PDR with a FAR, for forwarding IPv6 Neighbour Solicitation traffic to the SMF.

In this case, the user plane packets shall be forwarded between the CP and UP functions by encapsulating the user plane packets using GTP-U encapsulation (see subclause 5.3.1).

The SMF shall perform ARP proxying as specified in IETF RFC 1027 [32] respond to ARP  and/or IPv6 Neighbour Advertisement Proxying Solicitation as specified in IETF RFC 4861 [33] 3GPP TS 23.501 [28], subclause 5.6.10.2 in this case.

在这种情况下，SMF应响应ARP和/或IPv6 Neighbor Solicitaion。

5.13.3 ARP Address Resolution Protocol or IPv6 Neighbour Advertisement Proxying in Solicitation Response by UPF

If the SMF requests the UPF to do ARP respond to Address Resolution Protocol (ARP) (see IETF RFC 826 [32]) or IPv6 Neighbour Advertisement proxying Solicitation (see IETF RFC 4861 [33]) based on the local cache information for an Ethernet PDU session, the SMF shall provision a PDR in the UPF with:

如果SMF基于Ethernet PDU会话的本地缓存信息请求UPF响应Address Resolution Protocol（ARP）或IPv6 Neighbour Solicitaion，SMF应在UPF中提供PDR，包括：

- an Ethernet Packet Filter containing EtherType 2054 (hexadecimal 0x0806) and associate the PDR with a FAR that has the ARP bit in Proxying IE of the Forwarding Parameters IE set to 1; or

- a PDI containing an application ID such that the identified application ID matches against EtherType 34525 (hexadecimal 0x86DD), IPv6 Next Header type as 58 and ICMP Field Type as 135 and associate the PDR with a FAR that has the INS bit in Proxying IE of the Forwarding Parameters IE set to 1.

The UPF shall perform respond to ARP proxying as specified in IETF RFC 1027 [32] and/or IPv6 Neighbour Advertisement Proxying Solicitation as specified in IETF RFC 4861 [33] 3GPP TS 23.501 [28], subclause 5.6.10.2 in this case.