TU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010

kh

ITU/BDT
Arab
Regionall
Workshop
on


“4G
Wireless
Systems”


4G
Wireless
Systems


LTE
Technology


Session
4
:
Network
Architecture


Speakers
M.
Lazhar
BELHOUCHET
M
Hakim
EBDELLIM.
Hakim
EBDELLI
Date
27
.
29
January
2010


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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010

Agenda


.
Introduction
.
Evolved
Packet
System
(EPS)
Architecture
.
Network
Architecture
Evolution
.
LTE/SAE
N
LTE/SAE
Networkk
ElElements
.
LTE//SAE
Network
Interfaces
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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010 ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
Introduction


.
LTE/SAE architecture is driven by the goal to
optimize the system for packet data transfer.
.
No circuit switched components
.
New approach in the inter-connection between
radio access network and core network
.
The
EPS
architecture
is
made
up
of
an
EPC
(Packet
Core
Networkk,
allso
refferredd
as
SAE)
)
andd
an
eUTRAN
Radio
Access
Network
(also
referred
as
LTE)
.
.
The
CN
provides
access
to
external
packet
IP
The
CN
provides
access
to
external
packet
IP
networks
and
performs
a
number
of
CN
related
functions
(e.g.
QoS,
security,
mobility
and
terminal
context
management)
for
idle
(camped)
and
active
terminals


.
The
RAN
performs
all
radio
interface
related
functions
IMS/PDN
EPCeUTRANLTE-UE
EPS

EPS

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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010

Evolved Packet System (EPS) Architecture -Subsystems


E-UTRAN SAE or EPC


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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010 ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
Network
Architecture
Evolution


HSPA Direct tunnel I-HSPA LTE


HSPA R7 HSPA R7 LTE R8HSPA R6
SAE GWGGSN
SGSN
GGSN
SGSN MME/SGSN
GGSN
SGSN SGSN
RNC
SGSN MME/SGSNSGSN
RNC
Node B
(NB)
Node B +
RNC
Functionality
Evolved
Node B
(eNB)
Node B
(NB)
User plane
Control Plane

Control Plane

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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010 ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
Network
Architecture
Evolution
.Cont.


Internet
3GPP Rel 6 / HSPA
Node B RNC SGSN GGSN
User plane

.
.
Original 3G architecture

Original 3G architecture.


Control Plane
.
2 nodes in the RAN.
.
2 nodes in the PS Core Network.
.
Every Node introduces additional delay.
.
Common path for User plane and Control plane data.
.
Air interface based on WCDMA.


Air interface based on WCDMA.
.
RAN interfaces based on ATM.
.
Option for Iu-PS interface to be based on IP.


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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010 ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
Network
Architecture
Evolution
.Cont.


3GPP Rel 7 / Internet HSPA
Internet
SGSN
GGSN
Direct tunnel
Internet
Node B
(RNC Funct.)

User plane

User plane
Control Plane

.
I-HSPA introduces the first true flat architecture to WCDMA.
.
Standardized in 3GPP Release 7 as Direct Tunnel with collapsed RNC.
M fth RNCf i liti d hNdB


.
Most part of the RNC functionalities are moved to the Node B.
.
Direct Tunnels runs now from the GGSN to the Node B.
.
Solution for cost-efficient broadband wireless access.
.
Improves the delay performance (less node in RAN)
.
.
It can be deployable with existing WCDMA base stations.


Transmission savings

.
Transmission savings

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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010 ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
Network
Architecture
Evolution
.Cont.


3GPP Rel 8 / LTE MME
SAE GW
Direct tunnel
Internet
Evolved Node B
User plane

User plane
Control Plane


LTE takes the same Flat architecture from Internet HSPA

LTE takes the same Flat architecture from Internet HSPA.
Air interface based on OFDMA.
All-IP network.
New spectrum allocation (i.e 2600 MHz band)
Possibilityy to reuse spectrum ((i.e. 900 MHZ))

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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
LTE/SAE Network Elements
Evolved UTRAN (E-UTRAN) Evolved Packet Core (EPC)
HSS
S10
S6a
MME: Mobility Management Entity
PCRF:Policy & Charging Rule Function
LTE-UE
MME S11
S1-MME PCRF
S7
Evolved Rx+
Node B
(eNB)
X2
Serving
Gateway
S1-U
PDN
Gateway
PDN
S5/S8 SGi
cell
LTE-Uu
Main references to architecture in 3GPP specs.:
TS23 401 TS23 402 TS36 300
SAE
Gateway
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TS23.401,TS23.402,TS36.300
Network Architecture

ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
LTE U Evolved
LTE-UE
Evolved Node B (eNB)
Inter-cell RRM: HO, load balancing between cells
Radio Bearer Control:setup , modifications and
release Radio eNB Functions
Node B
cell (eNB)
LTE-Uu
of Resources
Connection Mgt. Control: UE State Mgmt. MME-UE
Connection
Radio Admission Control
. It is the only network element defined as part
of EUTRAN.
replaces the old Node eNode B Measurements Collection and evaluation
Dynamic Resource Allocation (Scheduler)
IP Header Compression/ de-compression
. It B / RNC combination
from 3G.
. It terminates the complete radio interface
including physical layer.
Access Layer Security: ciphering and integrity
protection on the radio interface
MME Selection at Attach of the UE
. It provides all radio management functions
. An eNB can handle several cells.
. To enable efficient inter-cell radio
User Data Routing to the SAE GW.
Transmission of Paging Message coming from MME
Transmission of Broadcast Info(System info, MBMS)
management for cells not attached to the
same eNB, there is a inter-eNB interface X2
specified. It will allow to coordinate inter-eNB
handovers without direct involvement of EPC
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during this process.
Network Architecture

ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
MME Functions
Control plane NE in EPC Mobility Management Entity (MME)
Evolved
Node B
(eNB) S1-MME MME
HSS
S6a
Non-Access-Stratum (NAS)
Security (Authentication,
integrity Protection)
State Mobility Handling
Serving
Gateway
S1-U
S11
Idle Tracking Area updates
Subscriber attach/detach
Radio Security Control
Signalling coordination for
. It is a pure signaling entity inside the EPC. SAE Bearer Setup/Release
. SAE uses tracking areas to track the position of idle UEs. The basic
principle is identical to location or routing areas from 2G/3G.
Trigger and distribution of
Paging Messages to eNB
Roaming Control (S6a interface
t . MME handles attaches and detaches to the SAE system, as well as
tracking area updates
. Therefore it possesses an interface towards the HSS (home subscriber
server) which stores the subscription relevant information and the
tl i d i it t d t b to HSS)
Inter-CN Node Signaling
(S10 interface), allows efficient
inter-MME tracking area updates
currently assigned MME in its permanent data base.
. A second functionality of the MME is the signaling coordination to setup
transport bearers (SAE bearers) through the EPC for a UE.
. MMEs can be interconnected via the S10 interface
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and attaches
Network Architecture

ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
Evolved
Node B
MME
Serving SAE Gateway
(eNB) S1-U
S1-MME
S5/S8
S11
S6a
Functions
Serving SAE
Gateway
PDN
Gateway
Local mobility anchor point:
Switching the user plane path to a
new eNB in case of Handover
Serving Gateway . The serving gateway is a network element that manages
the user data path (SAE bearers) within EPC.
. It therefore connects via the S1-U interface towards eNB
d i lik ktdt f h dt it
Mobility anchoring for inter-3GPP
mobility. This is sometimes referred
to as the 3GPP Anchor function
and receives uplink packet data from here and transmits
downlink packet data on it.
. Thus the serving gateway is some kind of distribution and
anchoring function within Idle Mode Packet Buffering and
notification to MME
packet data EPC. Packet Routing/Forwarding
. It relays the packet data within EPC via the S5/S8
interface to or from the PDN gateway.
. A serving gateway is controlled by one or more MMEs via
S11 i t f
between eNB, PDN GW and SGSN
Lawful Interception support
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interface.
Network Architecture

ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
Packet Data Network (PDN) SAE Gateway
MME PCRF
S7 Rx+
S11
S6a
PDN Gateway Functions
Mobility anchor for mobility between
3GPP access systems and non-3GPP
access systems is Serving
Gateway
S5/S8
PDN SAE
Gateway
PDN
SGi
Policy Enforcement (PCEF)
Per User based Packet i e
systems. This sometimes
referred to as the SAE Anchor function
. The PDN gateway provides the connection between
number of external data networks
Filtering (i.e.
deep packet inspection)
Charging & Lawful Interception support
EPC and a networks.
. Thus it is comparable to GGSN in 2G/3G networks.
. A major functionality provided by a PDN gateway is the
QoS coordination between the external PDN and EPC.
IP Address Allocation for UE
Packet Routing/Forwarding between
Serving GW and external Data Network
. Therefore the PDN gateway can be connected via S7
to a PCRF (Policy and Charging Rule Function).
Se g G a d e te a ata et o
Packet screening (firewall functionality)
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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
Policy and Charging Rule Function (PCRF)
MME
S5/S8 SGi
PCRF
S7 Rx+
S11
S6a
PCRF: Policy & Charging
Rule Function
QoS policy negotiation with PDN
Serving
Gateway
PDN SAE
Gateway
PDN
Charging Policy: determines how
packets should be accounted
Q p y g
. The PCRF major functionality is the Quality of Service
(QoS) coordination between the external PDN and EPC.
. Therefore the PCRF is connected via Rx+ interface to the
external Data network (PDN)
. This function can be used to check and modify the QoS
associated with a SAE bearer setup from SAE or to request
the setup of a SAE bearer from the PDN.
.This QoS management resembles the policy and charging
control framework introduced for IMS with UMTS release 6.
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co o a e o oduced o S U S e ease 6
Network Architecture

ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010

Home
Subscriber
Server
(HSS)


HSS

MME
S6a


S6a

.
The HSS is already introduced by UMTS
release
5


release 5.
.
With LTE/SAE the HSS will get additionally
data per subscriber for SAE mobility and service
handling


handling.
.Some changes in the database as well as in
the HSS protocol (DIAMETER) will be necessary
to enable HSS for LTE/SAE.


E/SAE.
.The HSS can be accessed by the MME via
S6a interface.

Permanent and central subscriber
database
HSS Functions
Stores mobility and service data for
every subscriber
Contains the Authentication Center Contains the Authentication Center
(AuC) functionality.
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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010 ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
LTE/SAE
Network
Interfaces


Evolved UTRAN (E-UTRAN) Evolved Packet Core (EPC)

HSS
S6a
MME: Mobility Management Entity
LTE-UE
MME S10
S1-MME PCRF
S7
Evolved
Node B
(eNB)
X2
S i
S1-U
S11
PDN
PDN
SGiS5/S8
(eNB)
cell
LTE U SAE Serving
Gateway
PDN
Gateway
LTE-Uu SAE
Gateway
User plane Control Plane Control Plane + User plane
Rx+
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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010 ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
LTE
Radio
Interface
and
the
X2
Interface


LTE-Uu

ff

(E)-RRC User PDUs User PDUs ..
Air interface of EUTRAN
Based on OFDMA in downlink and SC-FDMA in uplink
FDD and TDD duplex methods
Scalable bandwidth 1 4MHz to currently 20 MHz
(E) RRC
PDCP (ROHC = RFC 3095)
RLC
MAC
TS 36.300
Scalable bandwidth 1.4MHz to currently 20 MHz
Data rates up to 100 Mbps in DL
MIMO (Multiple Input Multiple Output) is a major
component although optional.
L )LTE-L1 (FDD/TDD-OFDMA/SC-FDMA)
eNBLTE-Uu
X2

Inter eNB interface
Handover coordination without involving the EPC

Handover coordination without involving the EPC

X2 X2AP: special signalling protocol


During HO, Source eNB can use the X2 interface to
forward downlink packets still buffered or arriving from
th i t tth ttNB

the serving gateway to the target eNB.

This will avoid loss of a huge amount of packets during
inter-eNB handover.


eNB

TS 36.420
[[currentlly also iin TS 36.300 §20]

l TS 36 300 §20]

User PDUs
X2-UP
(User Plane)
X2-CP
(Control Plane)
GTP-U
UDP
IP
TS 36.424
X2-AP
SCTP
IPTS 36.422
TS 36.423
L1/L2L1/L2TS 36.421 TS 36.421
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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010 ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
S1.MME
&S1.
U
Interfaces


S1-MME

S1 MME

S1-MME

Ctli f b NB dMME

Control interface between eNB and MME
S1flex allows 1 eNB to connect to several MME
MME and UE will exchange non-access stratum


signaling via eNB through this interface. TS 36.413

S1AP:S1 Application Protocol

S1-U

S1-U

eNB

User plane interface between eNB and serving

g
TS 36.411

Which Serving GW a user’s SAE bearer will have to
use is signaled from the MME of this user.


MME
(Control Plane)
NAS Protocols
S1-AP g g g
E.g.: if a UE performs a tracking area update the
TRACKING AREA UPDATE REQUEST message will
be sent from UE to eNB and the eNB will forward the
message via S1-MME to the MME.
SCTP
IP
L1/L2 TS 36.411
TS 36.412
(User Plane)
User PDUs
gateway.
It is a pure user data interface (U=User plane).
S1flex-U also supported: a single eNB can connect to
GTP-U
several Serving GWs.
Serving
GatewayUDP
IP
TS 36.414
L1/L2
TS 36.410
[currently in TS 36.300 §19]


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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010 ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
EUTRAN
&
EPC
connected
with
S1.flex


Several cases

eNB 1 Single S1-MME
Single S1-U

eNB
Single S1-MME
Multiple S1-U..S1Flex-U

eNB 3 Multipple S1MME
..S1Flex

Single S1-U

1
2
3
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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010 ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
S10
&
S6a
Interfaces


S10 Candidate
(Control Plane)

GTP-C
MME UDP
IP
L1/L2
TR 29.801

S10

Interface between different MMEs

Used during inter-MME tracking area updates

The new MME can contact the old MME the user had
been registered before to retrieve data about identity
(IMSI),), security information ((securityy context,,

(y
authentication vectors) and active SAE bearers (PDN
gateways to contact, QoS, etc.)

Obviously S10 is a pure signaling interface, no user
data runs on it.

S6a Candidate
(Control Plane)

HSSDIAMETER
MME HSS
SCTP
IP
L1/L2
DIAMETER
L1/L2
S6a Appl.
TR 29.801

S6a

Interface between the MME and the HSS

The MME uses it to retrieve subscription information
from HSS (handover/tracking area restrictions,
external PDN allowed, QoS, etc.) during attaches and
updates

The HSS can during these procedures also store the
user’s current MME address in its database.

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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010

S11
&
S5/S8
Interfaces



S11

Interface between MME and a Serving GW

A single MME can handle multiple Serving
GW each one with its own S11 interface
UUsedd to coordinate ththe establishhment of SAE f SAE

di bli
bearers within the EPC

SAE bearer setup can be started by the MME
(default SAE bearer) or by the PDN Gateway.

Serving
Gateway


User PDUs
S5/S8

Interface between Serving GW and PDN GW
S5IfS GW l tth

S5: If Serviing GW and PDN GW b d PDN GW belong to the same
network (non-roaming case)
S8:If this is not the case (roaming case)
S8 = S5 + inter-operator security functions
Mainly used to transfer user packet data between PDN GW

Mainly used to transfer user packet data between PDN GW
and Serving GW

Signaling on S5/S8 is used to setup the associated bearer
resources

S5/S8 can be implemented either by reuse of the GTP

PDN
Gateway


Sgi

User PDUs
TS 23.401 / TR 29.801

TS 23.402 / TR 29.801

www.cert.nat.tn 21 NetworkArchitecture
MME
S11 Candidate S11 Candidate
(Control Plane)
UDP
GTP-C
S5/S8 GTP Candidates
(Control and User Plane)
IP
L1/L2
S5/S8 IETF Candidates
(Control and User Plane)
p y
protocol from 2G/3G or by using Mobile IPv6 with some
IETF enhancements.
(Control and User Plane)
GTP-U
UDP
GTP-C
TR 29.801
(Control and User Plane)
MIPv6
Tunneling
Layer
PMIPv6
IPv6
PDNSgiUDP
IP
L1/L2
yLayer
IPv4/IPv6
L1/L2
IPv4
IPv6

PCRF
SGi
(User Plane)
??
IP
L1/L2
PDN
Gateway
IMS/PDNApplication
UDPTCPUDP or TCP
IPv4/IPv6
TR 23.401
Gateway
L1/L2
PCRF
SGi
(User Plane)
??
IP
L1/L2
PDN
Gateway
IMS/PDNApplication
UDPTCPUDP or TCP
IPv4/IPv6
TR 23.401
Gateway
L1/L2
ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
S7 (Control Plane)

S7
&
SGi
Intefaces


??

S7

Interface between PDN GW and PCRF
(Policy and Charging Rule Function)

It allows:
.the PCRF to request the setup of a SAE
bearer with appropriate QoS

.allows the PDN GW to ask for the QoS of

allows the PDN GW to ask for the QoS of
an SAE bearer to setup

.to indicate EPC status changes to the

SGi

PCRF to apply a new policy rule.
Interface used by the PDN GW to send and receive data to

Interface used by the PDN GW to send and receive data to
and from the external data network

It is typically either IPv4 or IPv6 based

Downlink data coming from the external PDN must be
assigned to the right SAE bearer of the right user by analysis

assigned to the right SAE bearer of the right user by analysis
of the incoming packet’s IP addresses, port numbers, etc.

This interface corresponds to the Gi interface in 2G/3Gnetworks

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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010 ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
Rx+
Interface


Rx+
(Control Plane)
S7 ??
PCRF ??
IP
L1/L2
SGi
TR 23.203
PDN
Gateway
PDN
R+

Rx+

Interface between PCRF(Policy & Charging Rules Function) and the external PDN
network/operators IMS
Standardized in 3GPP TS 23 203

Standardized in 3GPP TS 23.203.

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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010 ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
SAE/LTE
Interworking
with
2G/3G
Networks


SGSN
I PS
GERAN
Gr
GGSNGn
PDN
HSS
UTRAN
Iu-PS
MME
S6a
S7NB
LTE-UE
S1-U
S11
S1-MME
PDN
PCRF
S7
Rx+
SGiS5/S8
eNB
cell
Evolved UTRAN (E UTRAN)
PDN
Gateway
PDNcell
LTE-
Uu
Evolved UTRAN (E-UTRAN) Evolved Packet Core (EPC)
Gb Gi
S3S4
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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010 ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
S3
&
S4
Interfaces


(U Pl )S3 (User Plane)
UDP
GTP-C
GTP-U
User PDUs
SGSN
UDP
IP
L1/L2
UDP
IP
L1/L2
MME
TR 29.801 / TS 23.401
TR 29.801 / TS 23.401
MME
S4
S3
(Control Plane)
Serving
Gateway
Gateway


S3/S4

Interfaces between EPC and 2G/3G packet switched core network domain
They would allow inter-system changes between SAE and 2G/3G

ey syste ges /3G
The S3 is a pure signalling interface used to coordinate the inter-system change between MME and SGSN
The S4 is the user plane interface and it is located between SGSN and Serving SAE GW.
This would allow to either forward packet data from EUTRAN via Serving SAE GW to SGSN (and then to

GGSN) f 2G/3GRANt SGSNt S i SAEGWt PDNGW

GGSN) or from 2G/3G RAN to SGSN to Serving SAE GW to PDN GW.

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ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
SAE/LTE
Interworking
with
3G .Alternative


SGSNGERAN
Gb
Gr
GGSNGn
PDN
Gi
HSS
UTRAN
Gr
Direct Tunnels from
Serving GW to RNC
MME
S6a
S12
Serving GW to RNC
(User Plane)
MME
S1 U
S11
S1-MME PCRF
S7
Rx+
SGiS5/S8
eNB
Serving
Gateway
S1-U
PDN
Gateway
PDNSGiS5/S8cell
LTE-Uu
S3S4
Iu-PS
Evolved UTRAN (E-UTRAN)

Evolved Packet Core (EPC)


ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010

S12
Interface


S12S12
(User Plane)
User PDUs
Serving
Gateway

GTP-U
UDP
IP
L1/L2
UTRAN
S12
TR 29.801 / TS 23.401

Interfaces
between
EPC
and
3G
Radio
access
network
ItIt
wouldld
allllow
itinter.system
chhanges
between
SAESAE
and
3G

t
bt
d3G


The
S12
is
the
user
plane
interface
used
for
tunneling
user
data
directly
between
the
Serving
SAE
GW


and
the
UTRAN.


This
would
allow
to
forward
packet
data
from
3G
RAN
to
Serving
SAE
GW
to
PDN
GW


This
would
allow
to
forward
packet
data
from
3G
RAN
to
Serving
SAE
GW
to
PDN
GW.
It
is
based
on
the
Gn
interface
between
the
SGSN
and
the
GGSN
and
so
uses
the
GTP.
protocol.


www.cert.nat.tn 27 NetworkArchitecture

ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010

LTE/SAE
Roaming
Architecture
.Case


PCRF
Rx+
HSS
Home PLMN
PDN
Gateway
IMS/PDN
PCRF
S7
SGi
Visited PLMN
vPLMN
MME
S11
S1-MMEeNB
vPLMN
Serving
Gateway
S1-Ucell
LTE-Uu
hPLMN
S6a

S8

Evolved UTRAN (E-UTRAN) Evolved Packet Core (EPC)

Case 1:


Case 1:
Home Routed Traffic


By connecting Serving GW
in vPLMN to PDN GW in
hPLMN

GTP tunnel and MIPv6
options over the S8
interface

interface

Also called “Remote
Breakout”.

www.cert.nat.tn 28 NetworkArchitecture

ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010

LTE/SAE
Roaming
Architecture
.Case


Case 2: “Local Breakout”

Case 2: Local Breakout

UE can access the PDN network directly from the
vPLMN rather than traffic being routed through the
hPLMN. Breakout should depend on the service:

i e :internet access..local breakout

i.e.:internet access..local breakout
i.e.:access to corporate VPN..remote breakout
S9: PCRF-to-PCRF interface: roaming controlled

by hPLMN policies

S6a

Evolved UTRAN (E-UTRAN) Evolved Packet Core (EPC)

HSS
Home PLMN Home PLMNhPCRF
Visited PLMN
vPLMN
MME
S
S11
S1-MME
eNB vPCRF
S7
Rx+
SGiS51-USSGi
Serving
Gateway
PDN
cell
LTE-Uu
Gateway
IMS/PDN
S5
hPLMN
S9
www.cert.nat.tn 29 NetworkArchitecture

ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010 ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
S9
Interface


(Control Plane)
S9
??
??
IP
??
hPCRF vPCRF
IP
L1/L2
TR 29 801 / TS 23 401???????

TR 29.801 / TS 23.401???????

S9


Interfaces
between
the
hPCRF
and
the
vPCRFused
in
roaming
cases.
It
is
used
enforcement
in
the
VPLMN
of
dynamic
control
polices
from
the
HPLMN.


www.cert.nat.tn 30 NetworkArchitecture

ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010

LTE/SAE
Interworking
with
Non.3GPP
Access


Evolved Packet Core (EPC)

Evolved UTRAN (E-UTRAN)

Evolved UTRAN (E UTRAN)

Common GW for all accesses

. Generic support for any non-3GPP access
(e.g. WLAN, Fixed)
. Session Mobility using Mobile IP
. Policy control supported for non-3GPP
accesses
A th ti ti f 3GPP

. Access authentication for non-3GPP
accesses using Authentication,
Authorization and accounting (AAA)
mechanisms

. Securityy support for non-trusted accesses
pp

HSS
eNB
MME
S6a
S1 U
S1-MME
PCRF
S7
Rx+
cell
LTE-Uu
Serving
Gateway
S1-U S11
PDN
Gateway
PDNSGiS5
SAE
Gt Gateway GatewayGateway
Non-3GPP Access:
WiMAx, WLAN, Fixed,….
S2
www.cert.nat.tn 31 NetworkArchitecture

ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010 ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
Accounting
and
Charging
in
SAE/LTE
Networks


.
It
will
be
an
evolution
of
the
PS
Domain
charging
mechanisms
for
GPRS
and
UMTS


.
It
will
facilitate
seamless
interworking
with
legacy
charging
systems.


.
The
charging
filter
rules
are
provided
by
the
Policy

The
charging
filter
rules
are
provided
by
the
Policy
and
Charging
Rule
Function
(PCRF)
.


.
The
IMS
Charging
Function
provides
information
about
the
user’s
session
(
e
g
call
control


about
the
user
s
session
(e.g.
call
control,
multimedia,
services)
.


.
The
Application
Charging
Function
provides
infformation
abbout
thhe
content
off
thhe
user’’
s
traffffic


(e.g.
URL,
file
or
media
stream
name)
.
www.cert.nat.tn 32 NetworkArchitecture

ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010 ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010
Factors
affecting
the
price
of
a
user
session


.
Usage
time
or
duration.


.
Transferred
data
volume


.
Number
of
events
(units)


.
Destination
of
session


.
Location
and
time
zone
of
session
origination


.
QQualityy
of
Service
((QQoS)
)


.
Radio
Access
Technology
(RAT,
e.g.
LTE


and
3G/2G
in
the
case
of
handover,
nonnon.3GPP
access)3GPP
access)


.
Tariff
Time


.
User
identification


www.cert.nat.tn 33 NetworkArchitecture

ITU/BDT Arab Regional Workshop on “4G Wireless Systems” -Tunisia 2010

Thanks
for
your
Attention


Thanks
for
your
Attention


www.cert.nat.tn 34 NetworkArchitecture