7 Parameters

23.2143GPPArchitecture enhancements for control and user plane separation of EPC nodesRelease 17TS

7.1 Parameters for Sx session management

These parameters are used to control the functionality of the UP function related to an individual PDN connection, IP-CAN session, TDF session or TDF in unsolicited reporting mode as well as to inform about events occurring at the UP function. As the functionality of the respective UP functions differs, most parameters are specific to one or two of the reference points Sxa (between SGW-C and SGW-U), Sxb (PGW-C and PGW-U) and Sxc (TDF-C and TDF-U).

The Sx session management procedures however will use the relevant parameters in the same way for all Sx reference points: the Sx session establishment procedure as well as the Sx session modification procedure provide the control parameters to the UP function, the Sx session termination procedure removes all control parameters related to an Sx session and the Sx session level reporting procedure informs the CP function about events related to the Sx session that are detected by the UP function.

The parameters over Sx provided from CP function to UP function are grouped into session related parameters and four different rules, one "detection" rule and three different "enforcement" rules:

– Packet Detection Rule (PDR), with information describing what packets should receive a certain treatment (e.g. forwarding and other types of enforcement).

– Forwarding Action Rule (FAR), contains information on whether forwarding, dropping or buffering is to be applied to a packet.

– Usage Reporting Rule (URR), contains information that defines a certain measurement and how it shall be reported.

– QoS Enforcement Rule (QER), contains information related to QoS enforcement of traffic.

The UP function provides parameters over Sx to the CP function sending a Usage Report.

7.2 Session context

The session context comprises the session related parameters and all PDRs, URRs, QERs and FARs with the same Session ID.

The following table describes the session related parameters provided over Sx.

Table 7.2-1: Session related parameters

Attribute

Description

Comment

Applicability

SGW

PDN GW

TDF

Session ID

Uniquely identifies a session.

This session corresponds to a PDN connection for SGW, a PDN connection and an IP-CAN session for PGW, TDF session for TDF or a TDF in unsolicited reporting mode.

X

X

X

7.3 Packet Detection Rule

The following table describes the Packet Detection Rule (PDR) containing information required to classify a packet arriving at the UP function. There is at least one PDR per direction, e.g. UL direction or DL direction.

Table 7.3-1: Attributes within Packet Detection Rule

Attribute

Description

Comment

Applicability

SGW

PDN GW

TDF

Session ID

Identifies the session associated to this PDR

X

X

X

Rule ID

Unique identifier to identify this information.

X

X

X

Precedence

Determines the order, in which the detection information of all rules is applied

X

X

Packet detection information

Source interface

Contains the values "access side", "core side", "CP function" or "SGi-LAN".

Identifies whether the rule applies to incoming packets from the access side (i.e. up-link), the core side (i.e. down-link), the CP function (the packet from CP function) or the SGi-LAN side (the packet has experienced SGi-LAN Service Functions).

X

X

X

UE IP address

One IPv4 address and/or one IPv6 prefix with prefix length

Combination of UE IP address (together with Network instance, if necessary), F-TEID, SDF filters, application ID for traffic detection:

SGW UL: Local F-TEID

SGW DL: Local F-TEID

PGW UL: Local F-TEID + UE IP address + SDF/applicat.ID

PGW DL: UE IP address + SDF/application ID

TDF UL (solicited mode): UE IP address + SDF/application ID

TDF DL (solicited mode): UE IP address + SDF/application ID

TDF UL/DL (unsolicited mode): application ID

X

X

Network instance

Identifies the Network instance associated with the incoming packet. (NOTE 1).

X

X

X

Local F-TEID

X

X

List of SDF Filter(s)

X

X

Application ID

X

X

Outer header removal

Instructs the UP function to remove one or more outer header(s) (e.g. IP+UDP+GTP) from the incoming packet.

Any extension header shall be stored for this packet.

X

X

Forwarding Action Rule ID

The Forwarding Action Rule ID identifies a forwarding action that has to be applied.

X

X

X

List of Usage Reporting Rule ID(s)

Every Usage Reporting Rule ID identifies a measurement action that has to be applied.

X

X

X

List of QoS Enforcement Rule ID(s)

Every QoS Enforcement Rule ID identifies a QoS enforcement action that has to be applied.

X

X

X

NOTE 1: The Network instance is needed e.g. in the following cases:

– PGW/TDF-U supports multiple APN with overlapping IP addresses;

– PGW-U is connected to SGWs in different IP domains;

– SGW-U is connected to PGWs in different IP domains;

– SGW-U is connected to eNodeBs in different IP domains.

7.4 Usage Reporting Rule

The following table describes the Usage Reporting Rule (URR) that defines how a packet shall be accounted as well as when and how to report the measurements.

Table 7.4-1: Attributes within Usage Reporting Rule

Attribute

Description

Comment

Applicability

SGW

PDN GW

TDF

Session ID

Identifies the session associated to this URR

X

X

X

Rule ID

Unique identifier to identify this information.

X

X

X

Reporting triggers

One or multiple of the events can be activated for the generation and reporting of the usage report.

Applicable events include:

Start/stop of traffic detection with/without application instance identifier and deduced SDF filter reporting; Deletion of last PDR for a URR; Periodic measurement threshold reached; Volume/Time/Event measurement threshold reached; Immediate report requested; Measurement of incoming UL traffic; Measurement of discarded DL traffic.

X

X

X

Periodic measurement threshold

Defines the point in time for sending a periodic report for this URR key (e.g. timeofday)

This allows generation of periodic usage report for e.g. offline charging.

It can also be used for realizing the Monitoring time of the usage monitoring feature.

It can also be used for realizing the Quota-Idle-Timeout, i.e. to enable the CP function to check whether any traffic has passed during this time.

X

X

X

Volume measurement threshold

Value in terms of uplink and/or downlink and/or total byte-count when the measurement report is to be generated.

X

X

X

Time measurement threshold

Value in terms of the time duration (e.g. in seconds) when the measurement report is to be generated.

X

X

X

Event measurement threshold

Number of events (identified according to a locally configured policy) after which the measurement report is to be generated.

X

X

Inactivity detection time

Defines the period of time after which the time measurement shall stop, if no packets are received.

Timer corresponding to this duration is restarted at the end of each transmitted packet.

X

X

Event based reporting

Points to a locally configured policy which is identifies event(s) trigger for generating usage report.

X

X

Linked URR ID

Points to one or more other URR ID.

This enables the generation of a combined Usage Report for this and other URRs by triggering their reporting. See clause 5.2.2.4, TS 29.244 [12].

X

X

Measurement method

Indicates the method for measuring the network resources usage, i.e. the data volume, duration, combined volume/duration, or event.

X

X

X

Measurement information

Indicates specific conditions to be applied for measurements.

It is used to request:

– measurement before QoS enforcement, and/or

– to pause or set to active a measurement as for the Pause of charging, and/or

– to request reduced reporting for application start/stop events.

X

X

X

7.5 Forwarding Action Rule

The following table describes the Forwarding Action Rule (FAR) that defines how a packet shall be forwarded, including packet encapsulation/decapsulation and forwarding destination.

Table 7.5-1: Attributes within Forwarding Action Rule

Attribute

Description

Comment

Applicability

SGW

PDN GW

TDF

Session ID

Identifies the session associated to this FAR

X

X

X

Rule ID

Unique identifier to identify this information.

X

X

X

Network instance

Identifies the Network instance associated with the outgoing packet. (NOTE 1).

X

X

X

Destination interface

Contains the values "access side", "core side", "CP function", or "SGi-LAN".

Identifies the interface for outgoing packets towards the access side (i.e. down-link), the core side (i.e. up-link), the CP function side (i.e. towards CP function) or the SGi-LAN side (i.e. towards SGi-LAN).

X

X

X

Outer header creation

Instructs the UP function to add an outer header (IP+UDP+GTP) to the outgoing packet

Contains the F-TEIDu of peer entity (e.g. eNB, SGW, PGW, CP function).

Any extension header stored for this packet shall be added.

X

X

Send end marker packet(s)

Instructs the UP function to construct end marker packet(s) and send them out as described in clause 5.8.1.

This parameter should be sent together with the "out header creation" parameter of the new F-TEID-u.

X

X

Transport level marking

Transport level packet marking in the uplink and downlink, e.g. setting the DiffServ Code Point.

X

X

Forwarding policy

Reference to a preconfigured traffic forwarding treatment for FMSS or http redirection (NOTE 2)

Contains TSP ID or Redirect Destination and values for the forwarding behaviour (always, after measurement report (for termination action "redirect"))

X

X

Container for header enrichment

Contains information to be used by the UP function for header enrichment

Only relevant for the uplink direction

X

X

Buffer Control Information

Instructs the UP function on how to perform buffering

See clause 5.2.4 in TS 29.244 [12].

X

Delay Downlink Packet Notification Information

D parameter

See clause 5.9.3

X

Extended buffering Information

DL Data Buffer Expiration Time

See clause 5.9.3

X

DL Suggested Packet Count

See clause 5.9.3

NOTE 1: Needed e.g. in case:

– PGW/TDF-U supports multiple APN with overlapping IP addresses;

– PGW-U is connected to SGWs in different IP domains;

– SGW-U is connected to PGWs in different IP domains;

– SGW UP-U is connected to eNodeBs in different IP domains.

NOTE 2: The TSP ID action is enforced before the Outer header creation actions.

7.6 QoS Enforcement Rule

The following table describes the QoS Enforcement Rule (QER) that defines how a packet shall be treated in terms of bit rate limitation and packet marking for QoS purposes. All Packet Detection Rules that refer to the same QER share the same QoS resources, e.g. MBR.

Table 7.6-1: Attributes within QoS Enforcement Rule

Attribute

Description

Comment

Applicability

SGW

PDN GW

TDF

Session ID

Identifies the session associated to this QER

X

X

X

Rule ID

Unique identifier to identify this information.

X

X

X

QoS Enforcement Rule correlation ID

An identity allowing the UP function to correlate multiple Sessions for the same UE and APN.

Is used to correlate QoS Enforcement Rules for APN-AMBR enforcement

X

Gate status UL/DL

Instructs the UP function to let the flow pass or to block the flow

Values are: open, close, close after measurement report (for termination action "discard")

X

X

Maximum bitrate

The uplink/downlink maximum bitrate to be enforced for the packets.

This field may e.g. contain any one of:

– APN-AMBR (for a QER that is referenced by all relevant Packet Detection Rules of all PDN Connections to an APN)

– TDF session MBR (for a QER that is referenced by all Packet Detection Rules of a TDF Session)
– bearer MBR (for a QER that is referenced by all Packet Detection Rules of a bearer)

– SDF MBR (for a QER that is referenced by the uplink/downlink Packet Detection Rule of a SDF)

X

X

Guaranteed bitrate

The uplink/downlink guaranteed bitrate authorized for the packets.

This field contains:

– bearer GBR (for a QER that is referenced by all Packet Detection Rules of a bearer)

X

X

Down-link flow level marking

Flow level packet marking in the downlink.

For PGW, this is for controlling the SCI marking in the GTP extension header (for service indication towards GERAN as described in TS 23.060 [5]).

For TDF, this is for controlling the DSCP marking for application indication.

X

X

Packet rate

Number of packets per time interval to be enforced.

This field contains any one of:

– downlink packet rate for Serving PLMN Rate Control (the QER is referenced by all PDRs of the UE belonging to PDN connections using CIoT EPS Optimizations as described in TS 23.401 [2])

– uplink/downlink packet rate for APN Rate Control (the QER is referenced by all PDRs of the UE belonging to PDN connections to the same APN using CIoT EPS Optimizations as described in TS 23.401 [2]).

X

7.7 Usage Report generated by UP function

The UP function sends the usage report to inform the CP function about the measurement of an active URR or about the detection of application traffic of an active Packet Detection Rule. For each URR, the usage report may be generated repeatedly, i.e. as long as any one of the valid event triggers applies. A final usage report is sent for a URR when it is no longer active, i.e. either the URR is removed or all the references to this URR in any of the Packet Detection Rules belonging to the Sx session.

Following attributes can be included in the usage report:

Table 7.7-1: Attributes within Usage Report

Attribute

Description

Comment

Applicability

SGW

PDN GW

TDF

Session ID

Uniquely identifies a session.

This corresponds to a PDN connection for SGW and PGW or a TDF session for TDF

X

X

X

Rule ID

Uniquely identifies the Packet Detection Rule or Usage Reporting Rule within a session which triggered the report

Packet Detection Rule is only indicated when Reporting trigger is Detection of 1st DL packet on bearer (SGW) or Start/stop of traffic detection (PGW/TDF).

Usage Reporting Rule is indicated for all other Reporting triggers.

X

X

X

Reporting trigger

Identifies the trigger for the usage report.

Applicable values are:

Detection of 1st DL packet on bearer (only for SGW); Start/stop of traffic detection with/without application instance identifier and deduced SDF filter reporting (only for PGW and TDF); Deletion of last PDR for a URR; Periodic measurement threshold reached; Volume/Time/Event measurement threshold reached; Immediate report requested; Measurement of incoming UL traffic (only for PGW); Measurement of discarded DL traffic (only for SGW).

X

X

X

Start time

Provides the timestamp, in terms of absolute time, when the collection of the information provided within Usage-Information is started.

Not sent when Reporting trigger is Start/stop of traffic detection

X

X

X

End time

Provides the timestamp, in terms of absolute time, when the information provided within Usage-Information is generated.

Not sent when Reporting trigger is Start/stop of traffic detection

X

X

X

Measurement information

Defines the measured volume/time/events for this URR.

Contains DSCP of received packet when Reporting trigger is Detection of 1st DL packet on bearer (as described in TS 23.401 [2])

Contains application instance identifier and deduced SDF filter when Reporting trigger is Start/stop of traffic detection with application instance identifier and deduced SDF filter reporting (including deduced UE IP address for TDF in unsolicited mode)

Not sent when Reporting trigger is Start/stop of traffic detection without application instance identifier and deduced SDF filter reporting

X

X

X

7.8 Functional description

7.8.1 General

This clause describes how the CP function provides information over Sx to realize forwarding, reporting etc on different aggregation levels.

7.8.2 PDN connection and TDF session level context

The PDN connection or TDF session level context is realized over Sx by generating a Usage Reporting Rule and a QoS Enforcement Rule.

To apply PDN Connection or TDF session level reporting and MBR enforcement, the CP function provides over Sx:

– A URR that describes the reporting requirement for the PDN Connection or TDF session.

– A QER that describes the QoS enforcement actions that apply, i.e. a QER with APN-AMBR value (in case of PGW) or a QER with TDF session MBR (in case of TDF).

For session level reporting, the CP function includes references to the URR (i.e. URR Rule ID) in each Packet Detection Rule activated for the PDN Connection or TDF session. In case of PDN Connection or TDF session level usage monitoring where some SDF(s) are excluded, the CP function only includes a reference to the URR in those Packet Detection Rules that shall be included in the report.

For APN-AMBR policing, the CP function includes references (Rule ID) to the QER containing the APN-AMBR value in each Packet Detection Rule for non GBR traffic activated for the PDN Connection. The CP function shall apply the same QER for all Packet Detection Rules for non GBR traffic associated with any of the active PDN Connections of the same APN.

For TDF session MBR policing, the CP function includes references (Rule ID) to the QER containing the TDF session MBR value in each Packet Detection Rule activated for the TDF session.

7.8.3 Bearer related context

The bearer context is realized over Sx by generating one or two Forwarding Action Rules, a Usage Reporting Rule and a QoS Enforcement Rule that correspond to the bearer. In particular, the CP function may provide to the UP function for each active bearer:

– A Usage Reporting Rule that describes the reporting requirement for the bearer, including reporting events, measurement type etc for the bearer reports.

– A QoS Enforcement Rule that describe the QoS enforcement actions that apply to the bearer, including the bearer MBR.

– Forwarding Action Rules describe the forwarding behaviour for the bearer. One Forwarding Action Rule is required for the downlink direction (in case of PGW or SGW) and one for the uplink direction (in case of SGW).

NOTE: The CP function maintains the association between the EPS Bearer ID and the rules on Sx corresponding to bearer level enforcement and reports. There is no need to provide a Bearer ID to the UP function.

The CP function associates, based on the bearer binding decisions, every Packet Detection Rule that is activated for a bearer with the URR, QER and FARs applicable for the this bearer by including references (Rule IDs) in the PDR:

– For bearer level reporting, the CP function includes a reference (Rule ID) to the URR for the bearer.

– For bearer level policing, the CP function includes a reference (Rule ID) to the QER for the bearer.

– For forwarding of packets over a bearer (GTP-U encapsulation), the CP function includes a reference (Rule ID) to the FAR the bearer. This is done per direction (UL and DL).

7.8.4 Measurement key related context

The CP function provides a Usage Reporting Rule for each usage report that needs to be provided by the UP function. The CP function maintains a mapping between the Charging Key and/or Monitoring Key applicable for a SDF and the Measurement Key of the URR provided over Sx. For example, the CP function may provide one URR for each Charging Key and one URR for each Monitoring Key or may decide to provide a single URR for a Charging Key and a Monitoring Key in case there is complete overlap in the measurement requirements. Other mappings are also possible as determined by the CP function and is not limited by the standard as long as the reporting requirements from the CP function towards the OFCS/OCS and PCRF are fulfilled.

To associate traffic covered by a Packet Detection Rule with one or more measurement keys on Sx, the CP function includes in the Packet Detection Rule a reference to each URR (Rule ID) that is applicable for the traffic covered by the PDR.

7.9 Parameters for Sx management

7.9.1 Parameters for PFD management

The PGW-C/TDF-C can manage PFD sets in the applicable PGW-U/TDF-U independent of the Sx session. The management (provision or remove) of multiple PFD sets belonging to different Application IDs can be done with the same PFD management request message.

Table 7.9-1: Attributes within PFD management request message

Attribute

Description

Comment

Applicability

SGW

PDN GW

TDF

PFD(s)

Extension to the application detection filter

The provisioning of PFD(s) for an Application ID results in the removal of all PFD(s) stored in the PGW-U/TDF-U for this Application ID and the usage of all newly provided PFD(s) for this Application ID

X

X

Application ID

Application identifier which the PFD(s) is associated with

The provisioning of an Application ID without PFD(s) results in the removal of all stored PFD(s) corresponding to this Application ID

X

X

Annex A (informative):
Change history

Change history

Date

Meeting

TDoc

CR

Rev

Cat

Subject/Comment

New version

2016-09

SP-73

SP-160665

MCC Editorial update for presentation to TSG SA#73 for information and approval

1.0.0

2016-09

SP-73

MCC Editorial update for publication after TSG SA#73 approval

14.0.0

2016-12

SP-74

SP-160815

0002

2

F

Corrections to User Plane selection function

14.1.0

2016-12

SP-74

SP-160815

0003

5

F

Corrections to buffering in the user plane

14.1.0

2016-12

SP-74

SP-160815

0004

8

F

Sx parameter corrections

14.1.0

2016-12

SP-74

SP-160815

0005

4

B

SDCI support

14.1.0

2016-12

SP-74

SP-160815

0006

3

F

Update to PCC/ADC related functions

14.1.0

2016-12

SP-74

SP-160815

0007

2

F

Update to UP Selection Section

14.1.0

2016-12

SP-74

SP-160815

0008

2

F

Text updates for TS 23.401 call flows

14.1.0

2016-12

SP-74

SP-160815

0009

2

F

Text updates for TS 23.402 call flows

14.1.0

2016-12

SP-74

SP-160815

0010

2

B

Buffering and F-TEIDu Allocation

14.1.0

2016-12

SP-74

SP-160815

0012

3

F

Support of PGW Pause of Charging

14.1.0

2016-12

SP-74

SP-160815

0013

3

F

Sx Session Level Reporting Procedure update

14.1.0

2016-12

SP-74

SP-160815

0014

3

F

TDF-U selection in case of unsolicited reporting

14.1.0

2016-12

SP-74

SP-160815

0017

4

F

Corrections of Sx parameters

14.1.0

2016-12

SP-74

SP-160815

0019

F

Parameter alignment and corrections for traffic detection clause 

14.1.0

2016-12

SP-74

SP-160815

0020

2

F

Parameter alignment and corrections for forwarding section

14.1.0

2016-12

SP-74

SP-160815

0021

2

F

Alignment of function split clause 

14.1.0

2016-12

SP-74

SP-160815

0022

3

F

Clarification on the SGW-C partitions for a given UE

14.1.0

2017-03

SP-75

SP-170046

0026

2

F

Correction to enforcement of dynamic PCC/ADC rule

14.2.0

2017-03

SP-75

SP-170046

0027

2

F

Corrections to Sx parameters

14.2.0

2017-03

SP-75

SP-170046

0028

4

F

Session management procedure for TDF in unsolicited mode

14.2.0

2017-03

SP-75

SP-170052

0029

1

C

TS 23.214 support for transport level packet marking

14.2.0

2017-03

SP-75

SP-170046

0032

1

F

Updates Procedures in TS 23.060.

14.2.0

2017-06

SP-76

SP-170366

0033

1

F

Clean up and stage 3 alignment

14.3.0

2017-06

SP-76

SP-170366

0034

2

F

Corrections and clean up for 23.401 related message flows

14.3.0

2017-06

SP-76

SP-170366

0035

1

F

Addition of Sx node level procedures

14.3.0

2017-06

SP-76

SP-170366

0036

F

Clarification on pre-defined PCC rules

14.3.0

2017-06

SP-76

SP-170366

0038

F

Corrections and clean up for 23.203 related message flows

14.3.0

2017-06

SP-76

SP-170366

0039

1

F

Corrections and clean up for 23.060 related message flows

14.3.0

2017-06

SP-76

SP-170366

0040

F

Corrections and clean up for 23.402 related message flows

14.3.0

2017-09

SP-77

SP-170717

0041

2

F

Sx PDN Instance

14.4.0

2017-09

SP-77

SP-170717

0042

2

F

Update on activation of predefined PCC/ADC rules

14.4.0

2017-09

SP-77

SP-170717

0043

F

Description on Sx-u tunnel

14.4.0

2017-09

SP-77

SP-170717

0044

1

F

Corrections on PFD management

14.4.0

2017-09

SP-77

SP-170717

0045

F

Correlation of Sx Session and UE Context

14.4.0

2017-09

SP-77

SP-170717

0046

2

F

Update of the Procedures Specified in TS 23.401.

14.4.0

2017-09

SP-77

SP-170717

0048

3

F

Clarification of Procedures Specified in TS 23.060.

14.4.0

2017-09

SP-77

SP-170728

0047

2

B

Enable SGW-C & PGW-C selection of UPF to take UE’s NR capabilities into account

15.0.0

2017-12

SP-78

SP-170913

0050

1

A

Interface between MME and SGW-U for IoT data transmission

15.1.0

2017-12

SP-78

SP-170913

0052

2

A

Removal of PMIP-based procedures specified

15.1.0

2017-12

SP-78

SP-170920

0055

1

F

Correcting the condition for selection of SGW-U for NR as secondary RAT

15.1.0

2017-12

SP-78

SP-170940

0057

2

A

Update of the Procedures Specified in TS 23.060.

15.1.0

2018-03

SP-79

SP-180086

0060

1

A

Update of the Procedures Specified in TS 23.060.

15.2.0

2018-03

SP-79

SP-180086

0062

A

Update to Procedures Specified in TS 23.401

15.2.0

2018-03

SP-79

SP-180086

0064

1

A

Correction of SDF Filter Description in PDR Table

15.2.0

2018-06

SP-80

SP-180472

0066

1

A

Update of Sx parameter tables

15.3.0

2018-09

SP-81

SP-180711

0068

2

A

Application detection report when the PFDs are removed

15.4.0

2018-12

SP-82

SP-181081

0070

1

A

Addition of reference to SA WG5 OAM specification

15.5.0

2019-06

SP-84

SP-190406

0071

1

F

Corrections for the activation of usage reporting in the UP function

16.0.0

2019-06

SP-84

SP-190406

0072

F

Clarifications for 23.401 procedures

16.0.0

2020-07

SP-88E

SP-200429

0073

F

Clarification on the F-TEIDu allocation and release

16.1.0

2020-07

SP-88E

SP-200429

0074

1

F

Clarification of TEID allocation by gateway user plane

16.1.0

2020-09

SP-89E

SP-200686

0075

1

F

Corrections to CUPS Session/Bearer deactivation procedures

16.2.0

2021-06

SP-92E

SP-210346

0076

1

B

Support for L2TP on SGi

17.0.0