LTE Architecture

KANNAN MJTO(3G)

EPC

LTE System Architecture-EPS

E-UTRAN

eNode B

eNode B

P-GW

E UTRA

S-GW

HSSMME

Evolved Packet Core (EPC)

LTE System Architecture-EPS

Internet & Operator services

EPC

E-UTRAN

Evolved Packet Core (EPC)

2G/3G UTRAN

E- UTRAN

Operator Services

S-GWP-GW

HSS

Trusted IP NWs

Non-Trusted IP

NWs

ePDG

MME

EPC –Home Subscriber Server

Master subscriber database Stores user related information like, subscription

parameters, user identification, service profile, user location etc

Generates security related information It can be treated as an “upgraded HLR” with GSM, GPRS,

LTE and IMS information

EPC –Mobility Management Entity

Main control node Handles the control plane signaling Idle mode UE tracking Bearer activation / de-activation Choice of SGW and PGW for a UE Mobility anchoring Interacting with HSS to authenticate user Provides temporary identities for UEs Paging procedure Coordinating LI

EPC –Serving GateWay

A data plane element

An interface for the data packet network at the E-UTRAN.

The SGW maintains the data paths between the eNodeBs and the PDN Gateways

Routes user data packets between E-UTRAN and P-GW

When UEs move across areas served by different eNodeBs, the SGW serves as a mobility anchor ensuring that the data path is maintained

EPC –Packet Data Network GateWay

A data plane element

provides connectivity for the UE to external packet data networks

The UE may have connectivity with more than one PGW for accessing multiple PDNs

Charging

QoS control

IP address allocation

EPC – evolved PDG (ePDG)

Gateway used for Interworking with non trusted non

3GPP IP access systems

Provides some additional security mechanisms

Evolved UTRAN Architecture

E-UTRAN E-PC

X2

X2

X2

MME

S-GW

S1 -MME

S1- U

eNode B

The lone NE in the E-UTRAN Functionality of RNC moved to Node B, which reduces the number

of nodes and there by complexity and latency of the network It does the RRM functionality Controls the scheduling Transmission of paging & Broadcast information Selection of MME during registration Measurement configuration Routing of user data to the S-GW

eNode B Interfaces

S1 MME Connects eNodeBs with MME It is control / signaling plane interface

S1 U Connects eNodeBs with S-GW It is user plane interface It transports actual user data /packets

eNode B Interfaces

X2 Connects eNodeBs with neighboring e-NodeBs

e Node Bs communicate directly with each other for cell

reselection, intra LTE handover procedures, inter cell interference

coordination etc through this X2 interface.

This is some what similar to Iur interface of UMTS UTRAN

Advantages

Reduce Capax and Opex

Reduce Investment Risk

Quick responses to market opportunities

Improve users’ experience

Convergence Equipment Level

Site Level Operation Level

LTE in the coming future

SingleRANGSM / UMTS / HSPA / LTEGSM Expansion

One RAN, Simplify your NetworkOne RAN, Simplify your Network

Legacy GSM NetworkUMTS/HSPA Introduced

Disadvantages High CAPEX

- Buy systems separately

- Deploy systems separately

High OPEX- Operate systems separately- Maintain systems separately

Performance Down- Bad intersystem coordination- High intersystem interference

Reliability Down - Fault point & risk increasing

- Hard for trouble shooting

Core Network

Backhaul

www.3gpp.orgwww.radio-electronics.comwww.lteuniversity.comwww.cert.nat.tn

REFERENCES

Thank You

kannanmohanan@gmail.com