Completing the Convergence
Puzzle:
A Survey and A Roadmap
IEEE Wireless Communications‧June 2009
DJAMAL-EDDINE MEDDOUR, USMAN JAVAID, AND NICOLAS BIHANNIC,
ORANGE LABS
TINKU RASHEED, CREATE-NET RESEARCH CENTER
RAOUF BOUTABA, WATERLOO UNIVERSITY
698430005 蔡維倫
Outline
Introduction
 Convergence
 Existing Solutions
 Comparison
 Possible Timeframe
 Conclution

Introduction

This article surveys different technologies
which offer seamless handover and
converged access to mobile voice, video,
and data services
Home Network Convergence
The user can access different types of
services from the same terminal
 A service is available on more than one
handsets
 Diverse communication technologies are
expected within the home network
sphere

Home Network Convergence

Mainly : Home Gateway
◦ Local data exchange
◦ Interconnection to service platforms

SIP(Session Initiation Protocol) and IMS(IP
Multimedia Subsystem)
Access Network Convergence

Transport layer
◦ The reduction in operational
expenditure(OPEX) cost
 Aggregate mobile access nodes into a backhaul
network shared with a fixed access network
 The use of a shared infrastructure for
heterogeneous access solutions

Service control layer
◦ Allows to the same service irrespective of the
access network infrastructure
Core Network Convergence

IMS
◦ Mobile access network
 3GPP (3G Partnership Program)
◦ Fixed broadband access network
 TISPAN (Telecommunications and Internet
Converged Services and Protocols for Advanced
Networks) of ETSI (European Telecommunications
Standards Institute)
 ITU (International Telecommunications Union) of
NGN GSI (Next Generation Networks Global
Standard Initiative)
Core Network Convergence

The IMS is a core network infrastructure
to control user sessions for the following
services:
◦ Conversational services : voice and video
◦ Real-time data-oriented services : instant
messaging and presence
◦ Audio-visual services
Core Network Convergence

Benefits expected by the operator
deploying an IMS infrastructure
◦ To use a common functional infrastructure for
services control
◦ Allows the operator to better control
resources, especially significant in the mobile
domain for packet switching services
◦ Service triggering toward application servers
in accordance with user service profiles
◦ Solution for PSTN (public switched telephone
network) renewal and expectations of
OPEX/CAPEX (capital expenditure)
reductions
Application Server Level
Convergence
To offer differentiated QoS
 Consider it as a standalone convergence
for Web players

◦ Allows the operator to set policy on Qos an
charge for services accordingly
Existing Solution Toward Seamless
Convergence

WLAN (wireless local area network)
◦ High data rates to mobile users
◦ Low network deployment cost

UMTS (Universal Mobile
Telecommunications System)
◦ BSs in UMTS offer larger cells
◦ Provides nearly worldwide coverage
UMA (Unlicensed Mobile Access)
 I-WLAN (Interworking WLAN)
 MIH (media-independent handover)

UMA
Access network level
 Currently endorsed by the 3GPP under
GAN (generic access network)
 Offer call continuity from a GAN-capable
terminal between local area network and
the GSM infrastructure

UMA
Gb interface : 3GPP defined
 PSTN (public switched telephone
network)

UMA

Recent evolution : EGAN (enhanced GAN)
◦ Spec. TR 43.902
◦ Gb  Gn
◦ Allow GANC (GAN controller) to
interconnect directly with GGSN (GPRS
gateway service node)
◦ Interface between GAN terminal and GANC :
IPSec tunnel
 Strong security requirement
 piggyback
I-WLAN
3GPP standard
 Between a WLAN access network and
the 3GPP core network
 Architecture (release 6)

◦ WAG (wireless access gateway)
◦ PDG (packet data gateway)
◦ AAA server
I-WLAN

WAG
◦ Data from UE through fixed Ans are
aggregated at the WAG
◦ Route packets toward the home domain

PDG
◦ A gateway toward external PDNs (packet
data networks)

AAA server
◦ Interacts with PDG to perform service-level
AAA functions
I-WLAN protocols

Remote IP layer
◦ Route packets between UE and PDN

Tunneling layer
◦ Tunneling header
◦ Encapsulate remote IP layer packets
◦ Decrypt the IP packets

Transport IP layer
◦ Transport remote IP layer packets
encapsulated into IPSec tunnel
I-WLAN Evolution

SAE (System Architecture Evolution)
◦ Support seamless mobility between
heterogeneous access networks
◦ Mobility is under study for I-WLAN in release 8
and is based on MIP
◦ DSMIPv6
MIH

Defined : IEEE802.21 working group
◦ Defines a framework to support information
exchange that facilitates mobility decisions
◦ Support transparent service continuity
◦ Considered both wired and wireless
technologies
MIH

MIES、MICS、MIIS
Comparison
Possible Timeframe
Conclusion

Massive interest
◦ WiFi
 High data rates at low cost
 Do not guarantee seamless coverage, especially
with high mobility
◦ Bluetooth
 Supports low data rates (compared with hotspot
technologies)
 Saves in power
◦ GSM/GPRS and UMTS
 Wide area coverage and support high mobility
 High cost