This presentation provides an overview of 3GPP packet core and 5G systems. Some enabler features are outlined, such as network slicing. This presentation was prepared for the 20th Annual International Conference on Next Generation Internet and Related Technologies Net-Centric 2017 that was held at George Mason University.

1. 3GPP Packet Core Towards 5G
Communication Systems:
An Overview
Peyman TalebiFard, Senior Technical Staff

2. Net-Centric
20th Annual International Conference
on Next Generation Internet and Related
Technologies
January 16, 2018 – George Mason University

3. Outline
 5G System Architecture
 Network Slicing
 Support for Edge Computing
 Protocols, Interfaces and Notable Changes

4.  5G System Architecture
 Network Slicing
 Support for Edge Computing
 Protocols, Interfaces and Notable Changes

5. Ofinno Technologies, LLC
What is 5G?
 An end-to-end transformation of network architecture.
 Empowering socio-economic transformation.
 Connectivity.
 Higher capacity and Enhanced performance.
 New capabilities and use cases (enhanced Mobile Broadband (eMBB), mission
critical communication, and massive-scale connectivity for Internet of Things (IoT)
devices, such as sensors, wearables, smart vehicles.
5

6. Ofinno Technologies, LLC
4G Evolved Packet Core
6
3GPP TS 23.401 V15.1.0 (2017-09)
SGi
S12
S3
S1-MME
PCRF
Gx
S6a
HSS
Operator's IP
Services
(e.g. IMS, PSS etc.)
Rx
S10
UE
SGSN
LTE-Uu
E-UTRAN
MME
S11
S5Serving
Gateway
PDN
Gateway
S1-U
S4
UTRAN
GERAN
User /Data Plane
Control Plane

7. Ofinno Technologies, LLC
Evolved Packet Core & CUPS
7
3GPP TS 23.401 V15.1.0 (2017-09)
3GPP TS 23.214 V15.0.0 (2017-09)
SGi
S12
S3
S1-MME
PCRF
Gx
S6a
HSS
Operator's IP
Services
(e.g. IMS, PSS etc.)
Rx
S10
UE
SGSN
LTE-Uu
E-UTRAN
MME
S11
S5Serving
Gateway
PDN
Gateway
S1-U
S4
UTRAN
GERAN
SGi
S12
Operator's IP
Services
(e.g. IMS, PSS etc.)
S11
S5/8-C
Serving PDN
S1-U
S4 -C
Sd
TDF-U
GyGz
Gateway-U Gateway-U
S2a-C
S2b-C Gyn Gzn
S4-U
S2a-U
S2b-U
SGi
S6b
Gn/Gp-C
Gn/Gp-U
Gx
S5/8-U
TDF-C
PDN
Gateway-C
Serving
Gateway-C
Sxa Sxb Sxc
Gw
Gwn
CUPS
Control Plane User Plane Separation

8. Ofinno Technologies, LLC
5G System Architecture
8
TS 23.501 System Architecture for the 5G System, Stage 2 (Release 15)
UE (R)AN UPF
AF
AMF SMF
PCF UDM
DNN6
NRFNEF
N3
N2 N4
AUSF
Nausf Namf Nsmf
NpcfNnrfNnef Nudm Naf
NSSF
Nnssf
Control
Plane
User Plane
Service Based
Interaction
Control Plane User
Plane Separation
Simplified

9. Ofinno Technologies, LLC
5G Core Network Functions
 Termination of RAN CP interface
(N2).
 Termination of NAS (N1), NAS
ciphering and integrity protection.
 Registration management.
 Connection management.
 Reachability management.
 Mobility Management.
 Lawful intercept.
 Provide transport for SM messages
between UE and SMF.
 Transparent proxy for routing SM
messages.
 Access Authentication.
 Access Authorization.
 Provide transport for SMS messages
between UE and SMSF.
9
AMF: Access and Mobility Management Function
TS 23.501 System Architecture for the 5G System, Stage 2 (Release 15)

10. Ofinno Technologies, LLC
5G Core Network Functions
 Session Management e.g. Session
establishment, modify and release,
including tunnel maintenance
between UPF and AN node.
 UE IP address allocation &
management.
 Selection and control of UP
function.
 Configures traffic steering at UPF to
route traffic to proper destination.
 Lawful intercept.
 Charging data collection and
support of charging interfaces.
 Termination of SM parts of NAS
messages.
 Downlink Data Notification.
 Initiator of AN specific SM
information, sent via AMF over N2
to AN.
 Roaming functionality
10
SMF: Session Management Function
TS 23.501 System Architecture for the 5G System, Stage 2 (Release 15)

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5G Core Network Functions
 Anchor point for Intra-/Inter-RAT mobility
(when applicable).
 External PDU Session point of
interconnect to Data Network.
 Packet routing & forwarding (e.g. Uplink
classifier, Branching point, multi-homed
PDU session).
 Packet inspection (e.g. Application
detection based on service data flow
template and the optional PFDs received
from the SMF in addition).
 User Plane part of policy rule
enforcement.
 Lawful intercept (UP collection).
 Traffic usage reporting.
 QoS handling for user plane, e.g. UL/DL
rate enforcement.
 Downlink packet buffering and downlink
data notification triggering.
11
UPF: User Plane Function
TS 23.501 System Architecture for the 5G System, Stage 2 (Release 15)

12.  5G System Architecture
 Network Slicing
 Support for Edge Computing
 Protocols, Interfaces and Notable Changes

13. Ofinno Technologies, LLC
Network Slicing
 Provide a basis for
diverse services on the
same network
infrastructure.
 Each slice is composed
of 5G network
functions, some of
which can be shared
with other slices.
13
Reference: www.3GPP.org

14. Ofinno Technologies, LLC
Network Slicing
 Provides support for
vertical services.
 Provides isolation.
 Based on 3GPP, a
Network Slice within a
PLMN includes:
 The Core Network
Control Plane.
 User Plane Network
Functions.
14
Reference: www.3GPP.org

15. Ofinno Technologies, LLC
Network Slicing
15
Reference: www.3GPP.org

16. Ofinno Technologies, LLC
Isolation and Coexistence
16
3GPP TR 23.799 V14.0.0 (2016-12)
Network Slice
Deployment
Scenarios

17. Ofinno Technologies, LLC
Isolation and Coexistence
17
UPF
SMF 1
SMF 2
CN Instance #1
CP
Shared
(R)AN
CN Instance #2
CP
UP Instance #1
CN Instance #1
CP
UP
Shared
(R)AN
CN Instance #2
CP
UP
SMF 1
UPF-1
SMF 2
UPF-2

18.  5G System Architecture
 Network Slicing
 Support for Edge Computing
 Protocols, Interfaces and Notable Changes

19. Ofinno Technologies, LLC
Support for Edge Computing
 Edge computing enables operator and 3rd party services to be hosted close to the
UE's access point of attachment, so as to achieve an efficient service delivery
through the reduced end-to-end latency and load on the transport network.
 The 5G Core Network selects a UPF close to the UE and executes the traffic steering
from the UPF to the local Data Network via an N6 interface. This may be based on
the UE's subscription data, UE location, the information from Application Function
(AF), policy or other related traffic rules.
19
TS 23.501 System Architecture for the 5G System, Stage 2 (Release 15)

20. Ofinno Technologies, LLC
Support for Edge Computing
 To support traffic offloading for Edge Computing the SMF may control the data path
of a PDU (Packet Data Unit) session.
 Each PDU session anchor supporting a PDU session provides a different access to
the same DN. This can be achieved in essentially three ways:
 Usage of an Uplink Classifier functionality for a PDU session
 Usage of an IPv6 multi-homing for a PDU session
 Support for Local Area Data Network (LADN)
20
TS 23.501 System Architecture for the 5G System, Stage 2 (Release 15)

21. Ofinno Technologies, LLC
Uplink Classifier
 To support selective
traffic routing to the DN
or to support SSC mode
3.
 Traffic filters provided by
SMF.
 Insertion and removal
are decided by SMF.
 Generic N4 procedures
and UPF capabilities are
utilized.
21
UE AN
DN
N1 N2 N4 N4
N4
N6
N6
DN
N9
N9
N3 UPF
Uplink Classifier
N11
AMF SMF
Local access to the same DN
UPF
PDU session
anchor 1
UPF
PDU session
anchor 2
TS 23.501 System Architecture for the 5G System, Stage 2 (Release 15)

22. Ofinno Technologies, LLC
IPv6 Multi-homing
 A PDU Session may be
associated with multiple
IPv6 prefixes.
 The multi-homed PDU
Session provides access to
the Data Network via
more than one PDU
Session Anchor.
 The Branching Point
provides forwarding of UL
traffic towards the
different PDU Session
Anchors and merge of DL
traffic to the UE.
22
TS 23.501 System Architecture for the 5G System, Stage 2 (Release 15)
UE AN DN
N1 N2 N4 N4
N4
N6
N6
N9
N9
N3
UPF
PDU session
anchor 1
UPF
Branching Point
N11
AMF SMF
UPF
PDU session
anchor 2
make-before-break
PSA relocation

23. Ofinno Technologies, LLC
Local Area Data Network
 The UE explicitly requests a PDU session to a special APN/DNN.
 LADN Information is provided to the UE by the AMF during registration (e.g., LADN
DNN and LADN service area information).
 AMF tracks the UE and informs the SMF whether the UE is in the LADN service area.
 The UE may request a PDU session establishment for an available LADN when the
UE is located in the LADN service area.
23
TS 23.501 System Architecture for the 5G System, Stage 2 (Release 15)

24.  5G System Architecture
 Network Slicing
 Support for Edge Computing
 Protocols, Interfaces and Notable Changes

25. Ofinno Technologies, LLC
Protocol, Interfaces & Notable Changes
25
Lower Layer
UE
NAS-MM
NAS-
SM
SMS
Other
Lower Layer
NAS-MM
AMF
NAS Transport
NAS-
SM
SMF
SMS
SMSF
Other
Other NF
N11 / -Nsmf
N20 / -Nsmsf
Nother
TS 23.501 System Architecture for the 5G System, Stage 2 (Release 15)
NAS transport for SM, SMS and other services

26. Ofinno Technologies, LLC
Protocol, Interfaces & Notable Changes
26
TS 23.502 Procedures for the 5G System; Stage 2 (Release 15)
UPF
2.N4 Session Establishment Request
SMF
3.N4 Session Establishment Response
1.Trigger to establish PDU
session or relocate UPF
4.Interaction with other
network function
UPF
2.N4 Session Modification Request
SMF
3.N4 Session Modification Response
1.Trigger to modify PDU
session
4.Interaction with other
network function
SMF and UPF interactions over N4

27. Ofinno Technologies, LLC
Protocol, Interfaces & Notable Changes
Service Based Interaction (SBI) among NFs
27
NF_A
(Consumer
)
NF_B
(Producer)
ProducerRequest
Response
NF_A
(Consumer
)
NF_B
(Producer)
ProducerSubscribe
Notify
NF_A
(Consumer)
NF_B
(Producer)
ProducerSubscribe
Notify
NF_C
(Consumer)
Producer
TS 23.502 Procedures for the 5G System; Stage 2 (Release 15)
TS 23.501 System Architecture for the 5G System, Stage 2 (Release 15)

28. Ofinno Technologies, LLC
Protocol, Interfaces & Notable Changes
 The protocol stack for the
service based interfaces is
mainly based on HTTP.
 Details of SBI and protocol stack
are described in 3GPP TS 29.500.
28
Application
HTTP/2
TCP
IP
L2
L1
3GPP TS 29.500

29. References
 3GPP TS 29.500, 5G System; Technical Realization of Service Based
Architecture; Stage 3
 3GPP TS 23.501, System Architecture for the 5G System, Stage 2
(Release 15)
 3GPP TS 23.502, Procedures for the 5G System; Stage 2 (Release
15)
 3GPP TS 23.401 V15.1.0 (2017-09), General Packet Radio Service
(GPRS) enhancements for Evolved Universal Terrestrial Radio
Access Network (E-UTRAN) access.
 3GPP TS 23.214 V15.0.0 (2017-09), Architecture enhancements for
control and user plane separation of EPC nodes.

30. Contact
Peyman TalebiFard, PhD
Senior Technical Staff
Ofinno Tehnologies
Office: (571) 599-2923
www.ofinno.com
www.linkedin.com/in/peyman-talebifard

31. www.ofinno.com
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