Content for TS 23.214 Word version: 18.0.0

1… 4.3… 5… 5.6… 5.10… 6… 6.3… 6.3.1.2 6.3.1.3… 6.3.1.6… 6.3.2… 6.3.3… 6.3.3.4… 6.3.3.7… 6.3.4… 6.3.4.2… 6.3.4.2.2 6.3.4.3 6.4… 7…

4.3 High level functions 4.3.1 General 4.3.2 Functional split of SGW, PGW and TDF 4.3.3 User Plane Function selection 4.3.4 SGW-C Partitioning 4.4 Network elements 4.4.1 General 4.4.2 SGW control plane function 4.4.3 SGW user plane function 4.4.4 PGW control plane function 4.4.5 PGW user plane function 4.4.6 TDF control plane function 4.4.7 TDF user plane function
...

4.3 High level functions p. 10

4.3.1 General p. 10

This clause documents the existing functionality of SGW, PGW and TDF as described in TS 23.401, TS 23.402 and TS 23.203.

Table 4.3.1-1: Existing functionality of SGW, PGW and TDF

Main functionality	Sub-functionality	SGW	PGW	TDF
A. Session management (default & dedicated bearer establishment, bearer modification, bearer deactivation)	1. Resource management for bearer resources	X	X
	2. IP address and TEID assignment for GTP-U	X	X
	3. Packet forwarding	X	X
	4. Transport level packet marking	X	X
B. UE IP address management	1. IP address allocation from local pool		X
	2. DHCPv4 / DHCPv6 client		X
	3. DHCPv4 / DHCPv6 server		X
	4. Router advertisement, router solicitation, neighbour advertisement, neighbour solicitation (as in RFC 4861)		X
C. Support for UE mobility	1. Forwarding of "end marker" (as long as user plane to source eNB exists)	X
	2. Sending of "end marker" after switching the path to target node	X	X
	3. Forwarding of buffered packet	X
	4. Change of target GTP-U endpoint within 3GPP accesses	X	X
	5. Change of target GTP-U endpoint between 3GPP and non-3GPP access		X
D. S1-Release / Buffering / Downlink Data Notification	1. ECM-IDLE mode DL packet buffering; Triggering of Downlink Data Notification message generation per bearer (multiple, if DL packet received on higher ARP than previous DDN); Inclusion of DSCP of packet in DDN message for Paging Policy Differentiation	X
	2. Delay Downlink Data Notification Request (if terminating side replies to uplink data after UE service request before SGW gets updated)	X
	3. Extended buffering of downlink data when the UE is in a power saving state and not reachable (high latency communication); dropping of downlink data (if MME has requested SGW to throttle downlink low priority traffic and if the downlink data packet is received on such a bearer (see clause 4.3.7.4.1a of TS 23.401).	X
	4. PGW pause of charging procedure based on operator policy/configuration the SGW (failed paging, abnormal radio link release, number/fraction of packets/bytes dropped at SGW)	X	X
E. Bearer/APN policing	1. UL/DL APN-AMBR enforcement		X	X
	2. UL/DL bearer MBR enforcement (for GBR bearer)		X
	3. UL/DL bearer MBR enforcement (for nonGBR bearer on Gn/Gp interface)		X
F. PCC related functions	1. Service detection (DPI, IP-5-tuple)		X	X
	2. Bearer binding (bearer QoS & TFT)		X
	3. UL bearer binding verification and mapping of DL traffic to bearers		X
	4. UL and DL service level gating		X	X
	5. UL and DL service level MBR enforcement		X	X
	6. UL and DL service level charging (online & offline, per charging key)		X	X
	7. Usage monitoring		X	X
	8. Event reporting (including application detection)		X	X
	9. Request for forwarding of event reporting			X
	10. Redirection		X	X
	11. FMSS handling		X	X
	12. PCC support for NBIFOM		X
	13. DL DSCP marking for application indication			X
	14. Predefined PCC/ADC rules activation and deactivation		X	X
	15. PCC support for SDCI		X	X
G. NBIFOM	Non-PCC aspects of NBIFOM	X	X
H. Inter-operator accounting (counting of volume and time)	1. Accounting per UE and bearer	X	X
H. Inter-operator accounting (counting of volume and time)	2. Interfacing OFCS through reference points specified in TS 32.240	X	X	X
I. Load/overload control functions	Exchange of load/overload control information and actions during peer node overload	X	X
J. Lawful interception	Interfacing LI functions through reference points specified in TS 33.107 and performing LI functionality	X	X
K. Packet screening function			X
L. Restoration and recovery		X	X	X
M. RADIUS / Diameter on SGi			X
N. OAM interfaces		X	X	X
O. GTP bearer and path management	Generation of echo request, handling of echo response, echo request timeout and Error Indication message	X	X

4.3.2 Functional split of SGW, PGW and TDF p. 13

4.3.2.1 Functional split of SGW p. 13

The following Table describes the functionality of the SGW-C and the SGW-U.

All functionality performed by the SGW-U is controlled from the SGW-C and thus even if it is marked below as a SGW-U functionality only, there will be corresponding control functionality in the SGW-C.

For interfaces not listed in the Table below, Figure 4.2.1-1 describes whether they are terminated in SGW-C or SGW-U.

Table 4.3.2-1: Functional split of SGW

Main functionality	Sub-functionality	SGW-C	SGW-U	Comments
A. Session management (default & dedicated bearer establishment, bearer modification, bearer deactivation	1. Resource management for bearer resources	X	X	See clause 5.10
	2. IP address and TEID assignment for GTP-U	X	X	See clause 5.4
	3. Packet forwarding		X
	4. Transport level packet marking		X
C. Support for UE mobility	1. Forwarding of "end marker" (as long as user plane to source eNB exists)		X
	2. Sending of "end marker" after switching the path to target node	X	X	See clause 5.8
	3. Forwarding of buffered packet	X	X	See clause 5.9
	4. Change of target GTP-U endpoint within 3GPP accesses	X
	5. Change of target GTP-U endpoint between 3GPP and non-3GPP access			N/A
D. S1-Release / Buffering / Downlink Data Notification	1. ECM-IDLE mode DL packet buffering; Triggering of Downlink Data Notification message generation per bearer (multiple, if DL packet received on higher ARP than previous DDN); Inclusion of DSCP of packet in DDN message for Paging Policy Differentiation	X	X	See clause 5.9
	2. Delay Downlink Data Notification Request (if terminating side replies to uplink data after UE service request before SGW gets updated)	X
	3. Extended buffering of downlink data when the UE is in a power saving state and not reachable (high latency communication); dropping of downlink data (if MME has requested SGW to throttle downlink low priority traffic and if the downlink data packet is received on such a bearer (see clause 4.3.7.4.1a of TS 23.401).	X	X	See clause 5.9
	4. PGW pause of charging procedure based on operator policy/configuration the SGW (failed paging, abnormal radio link release, number/fraction of packets/bytes dropped at SGW)	X		See clause 5.3.4
G. NBIFOM	Non-PCC aspects of NBIFOM	X
H. Inter-operator accounting (counting of volume and time)	1. Accounting per UE and bearer		X	See clause 5.3
H. Inter-operator accounting (counting of volume and time)	2. Interfacing OFCS through reference points specified in TS 32.240	X		See clause 5.3
I. Load/overload control functions	Exchange of load/overload control information and actions during peer node overload			As defined in CT WG4 TS 29.244
J. Lawful interception	Interfacing LI functions through reference points specified in TS 33.107 and performing LI functionality	X	X	As defined in SA WG3-LI TS 33.107
L. Restoration and recovery				As defined in CT WG4 TS 29.244
N. OAM interfaces				As defined in SA WG5 TS 28.708
O. GTP bearer and path management	Generation of echo request, handling of echo response, echo request timeout and Error Indication message			As defined in CT WG4 TS 29.244

4.3.2.2 Functional split of PGW p. 15

The following Table describes the functionality of the PGW-C and the PGW-U.

All functionality performed by the PGW-U is controlled from the PGW-C and thus even if it is marked below as a PGW-U functionality only there will be corresponding control functionality in the PGW-C.

For interfaces not listed in the Table below, Figure 4.2.1-1 describes whether they are terminated in the PGW-C or the PGW-U.

Table 4.3.2-2: Functional split of PGW

Main functionality	Sub-functionality	PGW-C	PGW-U	Comments
A. Session management (default & dedicated bearer establishment, bearer modification, bearer deactivation)	1. Resource management for bearer resources	X	X	See clause 5.10
	2. IP address and TEID assignment for GTP-U	X	X	See clause 5.4
	3. Packet forwarding		X
	4. Transport level packet marking		X
B. UE IP address management	1. IP address allocation from local pool	X		See clause 5.5
	2. DHCPv4 / DHCPv6 client	X		See clause 5.5
	3. DHCPv4 / DHCPv6 server	X		See clause 5.5
	4. Router advertisement, router solicitation, neighbour advertisement, neighbour solicitation (as in RFC 4861)	X		See clause 5.5
C. Support for UE mobility	1. Forwarding of "end marker" (as long as user plane to source eNB exists)			N/A
	2. Sending of "end marker" after switching the path to target node	X	X	See clause 5.8
	3. Forwarding of buffered packet			N/A
	4. Change of target GTP-U endpoint within 3GPP accesses	X
	5. Change of target GTP-U endpoint between 3GPP and non-3GPP access	X
D. S1-Release / Buffering / Downlink Data Notification	1. ECM-IDLE mode DL packet buffering; Triggering of Downlink Data Notification message generation per bearer (multiple, if DL packet received on higher ARP than previous DDN); Inclusion of DSCP of packet in DDN message for Paging Policy Differentiation			N/A
	2. Delay Downlink Data Notification Request (if terminating side replies to uplink data after UE service request before SGW gets updated)			N/A
	3. Extended buffering of downlink data when the UE is in a power saving state and not reachable (high latency communication); dropping of downlink data (if MME has requested SGW to throttle downlink low priority traffic and if the downlink data packet is received on such a bearer (see 4.3.7.4.1a).			N/A
	4. PGW pause of charging procedure based on operator policy/configuration the SGW (failed paging, abnormal radio link release, number/fraction of packets/bytes dropped at SGW)	X		See clause 5.3.4
E. Bearer/APN policing	1. UL/DL APN-AMBR enforcement		X
	2. UL/DL bearer MBR enforcement (for GBR bearer)		X
	3. UL/DL bearer MBR enforcement (for nonGBR bearer on Gn/Gp interface)		X
F. PCC related functions	1. Service detection (DPI, IP-5-tuple)		X
	2. Bearer binding (bearer QoS & TFT)	X
	3. UL bearer binding verification and mapping of DL traffic to bearers		X	See clause 5.2
	4. UL and DL service level gating		X
	5. UL and DL service level MBR enforcement		X
	6. UL and DL service level charging (online & offline, per charging key)	X	X	See clause 5.3
	7. Usage monitoring	X	X	See clause 5.3
	8. Event reporting (including application detection)	X	X	Note: User-plane related events such as application detection reporting supported in UP function, while control-plane related events such as RAT change etc. supported only in CP function.
	9. Request for forwarding of event reporting			N/A
	10. Redirection	X	X	See clause 5.11.3
	11. FMSS handling		X
	12. PCC support for NBIFOM	X
	13. DL DSCP marking for application indication			N/A
	14. Predefined PCC/ADC rules activation and deactivation	X	X	See clause 5.11.1
	15. PCC support for SDCI	X	X	See clause 5.11.4
G. NBIFOM	Non-PCC aspects of NBIFOM	X
H. Inter-operator accounting (counting of volume and time)	1. Accounting per UE and bearer		X	See clause 5.3
H. Inter-operator accounting (counting of volume and time)	2. Interfacing OFCS through reference points specified in TS 32.240	X		See clause 5.3
I. Load/overload control functions	Exchange of load/overload control information and actions during peer node overload			As defined in CT WG4 TS 29.244
J. Lawful interception	Interfacing LI functions through reference points specified in TS 33.107 and performing LI functionality	X	X	As defined in SA WG3-LI TS 33.107
K. Packet screening function			X
L. Restoration and recovery				As defined in CT WG4 TS 29.244
M. RADIUS / Diameter on SGi		X	X	See clause 5.5
N. OAM interfaces				As defined in SA WG5 TS 28.708
O. GTP bearer and path management	Generation of echo request, handling of echo response, echo request timeout and Error Indication message			As defined in CT WG4 TS 29.244

4.3.2.3 Functional split of TDF p. 18

The following Table describes the functionality of the TDF-C and the TDF-U.

All functionality performed by the TDF-U is controlled from the TDF-C and thus even if it is marked below as a TDF-U functionality only there will be corresponding control functionality in the TDF-C.

For interfaces not listed in the Table below, Figure 4.2.1-1 describes whether they are terminated in the TDF-C or TDF-U.

Table 4.3.2-3: Functional split of TDF

Main functionality	Sub-functionality	TDF-C	TDF-U	Comments
E. Bearer/APN policing	1. UL/DL APN-AMBR enforcement		X	Not identical to APN-AMBR enforcement as it a) covers every flow in TDF session and b) does not cover other TDF sessions of the UE to the same APN
	2. UL/DL bearer MBR enforcement (for GBR bearer)			N/A
	3. UL/DL bearer MBR enforcement (for nonGBR bearer on Gn/Gp interface)			N/A
F. PCC related functions	1. Service detection (DPI, IP-5-tuple)		X
	2. Bearer binding (bearer QoS & TFT)			N/A
	3. UL bearer binding verification and mapping of DL traffic to bearers			N/A
	4. UL and DL service level gating		X
	5. UL and DL service level MBR enforcement		X
	6. UL and DL service level charging (online & offline, per charging key)	X	X	See clause 5.3
	7. Usage monitoring	X	X	See clause 5.3
	8. Event reporting (including application detection)	X	X	Note: User-plane related events such as application detection reporting supported in UP function, while control-plane related events such as RAT change etc. supported only in CP function.
	9. Request for forwarding of event reporting	X
	10. Redirection	X	X	See clause 5.11.3
	11. FMSS handling		X
	12. PCC support for NBIFOM			N/A
	13. DL DSCP marking for application indication		X
	14. Predefined PCC/ADC rules activation and deactivation	X	X	See clause 5.11.1
	15. PCC support for SDCI	X	X	See clause 5.11.4
H. Inter-operator accounting (counting of volume and time)	1. Accounting per UE and bearer			N/A
H. Inter-operator accounting (counting of volume and time)	2. Interfacing OFCS through reference points specified in TS 32.240	X		See clause 5.3
I. Load/overload control functions	Exchange of load/overload control information and actions during peer node overload			As defined in CT WG4 TS 29.244
L. Restoration and recovery				As defined in CT WG4 TS 29.244
N. OAM interfaces				Not defined by SA WG5

4.3.3 User Plane Function selection p. 20

The CP function of a functional entity performs selection of its respective UP function considering parameters such as UE's location information, capability of the UP function and features required for an UE. Additionally, the selection of UP function shall consider UP function deployment scenarios such as centrally located UP function and distributed UP functions located close to or at the RAN site. The selection of UP function shall also allow deployment of UP functions with different capabilities, e.g. UP functions supporting no or a subset of optional functionalities.

For standalone CP functions:

SGW's CP function shall select SGW's UP function;
PGW's CP function shall select PGW's UP function;
TDF's CP function shall select TDF's UP function.

Combined SGW/PGW's CP function should select either combined SGW/PGW UP function or standalone SGW UP and PGW UP functions.

For details, refer to clause 5.12.

4.3.4 SGW-C Partitioning p. 20

If the SGW-U service area is smaller than the SGW-C service area, the SGW-C can be partitioned into multiple SGW-C partitions. Each of the SGW-C partition is aligned with the corresponding SGW-U service area. The MME treats the SGW-C partition as legacy SGW.

4.4 Network elements p. 21

4.4.1 General p. 21

SGW-C and SGW-U jointly provide functionality equivalent to the functionality provided by SGW as defined by the TS 23.401.

PGW-C and PGW-U jointly provide functionality equivalent to the functionality provided by PGW as defined by the TS 23.401 and TS 23.402, and the PCEF as defined by the TS 23.203.

TDF-C and TDF-U jointly provide functionality equivalent to the functionality provided by TDF as defined by the TS 23.203.

The clause 4.3.2 defines how the functional control and user plane split is done and which functionality SGW-C, SGW-U, PGW-C, PGW-U, TDF-C, TDF-U correspondingly support.

4.4.2 SGW control plane function p. 21

The SGW control plane function (SGW-C) provides the functionality of the SGW as defined by TS 23.401 except for the functions that are performed by the SGW-U as described in Table 4.3.2-1.

In addition, the SGW-C is responsible for selecting the SGW-U (as described in clause 4.3.3) and for controlling the SGW-U with respect to the functions described in Table 4.3.2-1.

4.4.3 SGW user plane function p. 21

The SGW user plane function (SGW-U) provides the functionality described in this TS. The functions that are performed by the SGW-U are listed in Table 4.3.2-1 together with a reference to a detailed functional description in clause 5 for some of them. The control parameters relevant for the SGW-U are described in clause 7.

4.4.4 PGW control plane function p. 21

The PGW control plane function (PGW-C) provides the functionality of the PGW as defined by TS 23.401 and TS 23.402, and the PCEF as defined by the TS 23.203 except for the functions that are performed by the PGW-U as described in Table 4.3.2-2.

In addition, the PGW-C is responsible for selecting the PGW-U (as described in clause 4.3.3) and for controlling the PGW-U with respect to the functions described in Table 4.3.2-2.

4.4.5 PGW user plane function p. 21

The PGW user plane function (PGW-U) provides the functionality described in this TS. The functions that are performed by the PGW-U are listed in Table 4.3.2-2 together with a reference to a detailed functional description in clause 5 for some of them. The control parameters relevant for the PGW-U are described in clause 7.

4.4.6 TDF control plane function p. 22

The TDF control plane function (TDF-C) provides the functionality of the TDF as defined by TS 23.203 except for the functions that are performed by the TDF-U as described in Table 4.3.2-3.

In addition, the TDF-C is responsible for selecting the TDF-U (as described in clause 4.3.3) and for controlling the TDF-U with respect to the functions described in Table 4.3.2-3.

4.4.7 TDF user plane function p. 22

The TDF user plane function (TDF-U) provides the functionality described in this TS. The functions that are performed by the TDF-U are listed in Table 4.3.2-3 together with a reference to a detailed functional description in clause 5 for some of them. The control parameters relevant for the TDF-U are described in clause 7.