4G convergent architecture

SPECIAL TOPIC SEMINAR ON
SOLUTION TO CHARGING AND BILLING OF
CONVERGENT ARCHITECTURE IN 4G
NETWORK
PREPARED BY:-
VINITA BHANDWAD
READING ME(EXTC) SEM III(13113A0003)
VIT, WADALA
Solution to Charging and Billing in 4G Network VIT

CONTENTS:
 Introduction to Generations.
 Various Generations.
 Limitations and Drawbacks of 3G Network.
 Leap towards 4G.
 4G Technology.
 Features of 4G Technology.
 Challenges in 4G.
 Applications in 4G.
 4G Architecture.
 Advantages and Disadvantages of 4G.
 Billing Issue in 4G.
 Proposed Solution to Billing issue.
 Simulation Results.
 Literature Survey.
 References.
 Conclusion. Solution to Charging and Billing in 4G Network VIT

Introduction to Generations
 G stands basically for Generation.
 As we are progressing towards the Telecommunication and wireless
industry we are moving towards the future generations.
 G basically defines about the data speeds used for Internet etc.

Various Generations.
 1G
 2G
 2.5G
 3G
 4G
 Future Generation 5G

Cont….
 1G refers to the first generation of wireless telephone technology, mobile
telecommunications which was first introduced in 1980s and completed in
early 1990s.
 It's Speed was upto 2.4kbps.
 It allows the voice calls in 1 country.
 1G network use Analog Signal.
 AMPS was first launched in USA in 1G mobile systems
 Key ideas:
 Exclusively analog
 Geographical area divided into cells (typically 10-25km)
 Cells are small: Frequency reuse exploited in nearby (not adjacent) cells
 As compared to IMTS, could use 5 to 10 times more users in same area
by using frequency re-use (divide area into cells)
 Smaller cells also required less powerful, cheaper, smaller devices

Cont….
Drawbacks of 1G:
 Poor Voice Quality
 Poor Battery Life
 Large Phone Size
 No Security
 Limited Capacity
 Poor Handoff Reliability

Cont….
 2G technology refers to the 2nd generation which is based on GSM.
 It was launched in Finland in the year 1991.
 2G network use digital signals.
 It’s data speed was upto 64kbps.
Features Includes:
 It enables services such as text messages, picture messages and
MMS (multi media message).
 It provides better quality and capacity .

Cont….
Drawbacks of 2G:
 2G requires strong digital signals to help mobile phones work. If
there is no network coverage in any specific area digital signals
would be weak.
 These systems are unable to handle complex data such as Videos.
 Angular decay curve

Differences Between First and Second Generation
Systems
 Digital traffic channels – first-generation systems are almost purely analog; second-
generation systems are digital.
 Encryption – all second generation systems provide encryption to prevent
eavesdropping.
 Error detection and correction – second-generation digital traffic allows for detection
and correction, giving clear voice reception.
 Channel access – second-generation systems allow channels to be dynamically
shared by a number of users.

Cont….
 2.5G is a technology between the second (2G) and third (3G) generation of mobile
telephony.
 2.5G is sometimes described as 2G Cellular Technology combined with GPRS.
Features Includes:
 Phone Calls
 Send/Receive E-mail Messages
 Web Browsing
 Speed : 64-144 kbps
 Camera Phones
 Take a time of 6-9 mins. to download a 3 mins Mp3 song.

Cont….
 3G technology refer to third generation which was introduced in
year 2000s.
 Data Transmission speed increased from 144kbps- 2Mbps.
 Typically called Smart Phones and features increased its bandwidth
and data transfer rates to accommodate web-based applications and
audio and video files.

FEATURES OF 3G TECHNOLOGY
 Providing Faster Communication
 Send/Receive Large Email Messages
 High Speed Web / More Security
 Video Conferencing / 3D Gaming
 TV Streaming/ Mobile TV/ Phone Calls
 Large Capacities and Broadband Capabilities
 11 sec – 1.5 min. time to download a 3 min Mp3 song.
 Voice quality comparable to the public switched telephone network
 144 Kbps- user in high-speed motor vehicles
 384 Kbps- pedestrians standing or moving slowly over small areas
 Up to 2 Mbps- fixed applications like office use
 Symmetrical/asymmetrical data transmission rates
 Support for both packet switched and circuit switched data services
like Internet Protocol (IP) traffic and real time video

LIMITATIONS AND DRAWBACKS OF 3G
TECHNOLOGY
 Expensive fees for 3G Licenses Services
 It was challenge to build the infrastructure for 3G
 High Bandwidth Requirement
 Expensive 3G Phones.
 Large Cell Phones.

4G TECHNOLOGY

Leap Towards 4G
 To provide user friendliness
 To provide user personalization
 High performance
 Interoperability
 Network convergence
 Low power consumption
 Low cost

4G Technology
 4G technology refer to or short name of fourth Generation which was started from
late 2000s.
 Capable of providing 100Mbps – 1Gbps speed.
 The Necessicity of higher speed is required to fulfill the tremendous requirement for
some application s such as face book, YouTube etc.
Table 1

Cont…
 One of the basic term used to describe 4G is MAGIC.
 MAGIC:
 Mobile Multimedia
 Anytime Anywhere
 Global Mobility Support
 Integrated Wireless Solution
 Customized Personal Services
 Also known as Mobile Broadband Everywhere

Cont….
 The next generation of wireless communication tech known as fourth generation(4G)
allows operators to use new and wider spectrum and supplements 3G & 3.5G wireless
technologies with higher user data rates & expanded multimedia services. .
 Capable to provide speed 100Mbps-1Gbps.
 Provide any kind of service at any time as per user requirements, anywhere.
 The two wireless technologies that have been considered as aspirants to achieve
wireless performance are LONG TERM EVOLUTION & WIMAX.
 The goal of 4G is to allow users to access internet anytime anywhere.

Cont…
 4G networks or what it is rightly called today future networks could be treated as a
composition of complicated heterogeneous networks.
 These heterogeneous networks on converged platform provide access to varied
services over an IPv6 core.
 Charging, accounting and Billing are a few such major issues with such
networks. Currently the users are confined to utilize the services provided only
by their home network providers.
 Convergence would provide freedom to use compounded services from varied
network operators.
 Presently the charging schemes for mobiles are quite simple and are driven by the
network operators to lure new consumers and maintain their existing consumers.
Consumers are charged based on their usage and subscription.

Cont…
 The rapid developments in terms of the user equipment like mobiles, smart
devices, hand-held terminals etc. have contributed greatly by accelerating the
realization of 4G networks.
 The development of advance technologies like LTE and Wi-MAX will realize
high speed switching with high quality of service and greater functionality.
 Billing in 4G has become much more complicated because of 4G networks.
 This is mainly due to heterogeneity of 4G networks and the frequent
interaction of service providers.

Key features of 4G:
 Network Detection and Network Selection — A mobile terminal that features
multiple radio technologies or possibly uses software-defined radios if economical,
allows participation in multiple networks simultaneously, thereby connecting to the
best network with the most appropriate service parameters (cost, QoS and capacity
among others) for the application.
 Seamless Handover and Service Continuity — A “base station” that features
intra- and inter-technology handovers, assuring service continuity with zero or
minimal interruption, without a noticeable loss in service quality. Support for this
function requires continuous transparent maintenance of active service instances
and inclusion of various access technologies, from Wi-Fi to OFDMA.

Challenges in 4G:
 Security: The first step in analyzing cellular wireless security is to identify the
security objectives. The goals that the security policy and corresponding technology
should achieve are to ensure that information generated by or relating to a user is
adequately protected against misuse or misappropriation. It is to be ensured that the
level of protection afforded to users and providers of services is considered to be
better than that provided in contemporary fixed and mobile networks. Further, it is to
be seen that the implementation of security features and mechanisms can be
extended and enhanced as required by new threats and services.

CONT…
 Hand off Delay: Handoff delay poses another important QoS-related issue in
4G wireless networks. During the handoff process, the user may experience a
significant drop in QoS that will affect the performance of both upper-layer protocols
and applications. Deploying a priority-based algorithm and using location-aware
adaptive applications can reduce both handoff delay and QoS variability. When there
is a potential for considerable variation between senders’ and receivers’ device
capabilities, deploying a receiver-specific filter in part of the network close to the
source can effectively reduce the amount of traffic and processing, perhaps
satisfying other users’ QoS needs.
 4G supportive devices showing less Battery Backup: In 4G supportive Devices
due to presence of large number of Transmitters & Receivers, the battery of the
device runs off quite quickly. With technological developments the devices are
getting smaller in size due to Large Scale Integration and micro architecture. Hence
in 4G devices if we want to enhance the battery life by designing a much powerful Li-
on Battery ,then the backup would increase no doubt but also the size o the device
would increase i.e. not highly recommended.

Application of 4G:
 Multimode Software Application: 4G technology has an unique application of accessing several
wireless networks. It is capable of high level of customization at the user-level end. This feature
integrates the infrastructure of all available networks and steadily it will be easier for users to access
services and applications regardless of the environment. One can easily access different mobile and
wireless networks simultaneously. Multimode software is a software that allows the user device to
adapt itself to various wireless interfaces networks in order to provide constant net access with high
data (packet based) rate. Figure 3 shows how multiple networks are accessed through multimode
operation. All the networks will be compatible once the switch is completed, eliminating roaming and
areas where only one type of phone is supported. Once the voice and data networks are superposed
there will suddenly be millions of new devices on the network cloud. This will require either
reconstruction of the address space for the entire Internet or using different address spaces for the
existing wireless networks. The multimode device architecture may improve call completion and
expand effective coverage area.
 Video Network Coding for 4G Wireless networks: High Definition (HD) demand is increasing day by
day more than that of the bandwidth support available. Network Coding allows to reduce the required
number of packets to complete a transmission over noisy or unreliable networks compared non coded
version, hence increasing throughput. Network coding offers exciting possibilities for the efficient
transmission of video over wireless and bottleneck networks . By sending combinations of packets and
considering traffic as algebraic information not just bits, 4G network is ideally suited to Network Coding
i.e. they are resources, need to serve a variety of different devices and femto cells connected to WIFI.
However, it is also noted that the complexities that Network Coding can face in decoding nodes can
accelerate the capabilities of embedded systems. This problem can be discarded by use of codes
defined on small Galois Fields (GF). Thus, it is inferred that Network Coding could be doing peer to
peer high definition video streaming and also thereby can be incorporated into more consumer-oriented
devices. In the next section, the proposed strategy for Video Centric Network Coding has been briefly
portrayed.

4G NETWORK ARCHITECTURE
Figure 1

Cont…
 Figure 1 shows the widely accepted 4G network structure with IP as the core
network used for communication; integrating the 2G, 3G and 4Gtechnologies
using a convergence layer.
 This architecture fulfils the basic requirement of servicing the standalone and
mobile subscribers on an “anytime, anywhere, anyhow” basis in dynamic
network conditions.

SWOT ANALYSIS OF 4G
Strengths in 4G:
 4G visions take into account installed base and past investments
 Strong position of telecommunications vendors expected in the marketplace
 Faster data transmission and higher bit rate and bandwidth, allow more
business applications and commercialization.
 Has advantage for personalized multimedia communication tools
Weakness in 4G:
 No large user community for advanced mobile data applications yet Growing
divergence between telecommunications vendors and operators
 Not possible to offer full internet experience due to limited speed and
Bandwidth
 Comparatively higher cost to use and deploy infrastructure compared fast
mobile generation

Opportunities in 4G:
 Evolutionary approach may yield opportunities for the 4G.
 Sophisticated and mature commercialization of 4G technology would encourage more
applications of e-commerce and m-commerce.
 Worldwide economy recover stimulates consumption and consumer confidence,
therefore bring in opportunities for telecommunication sections
 It is expected and predicted that consumers will continue to replace handsets with newer
technology at a fast rate.
 - Desirable higher data capacity rates, the growth opportunity for 4G is very bright and
hopeful
Threats in 4G:
 Faster rate of growth and developments in other region
 Since 3G mobile is still in the market, it squeezes the market competition in the mobile
industry
Conclusion:
 As we come up with the SWOT analysis out of this 4G technology, it is inevitable that
4G would completely replace 3G in a long run. Nevertheless, 4G and 3Gtend to keep a
co-competitive relationship in a short run. In order for 4G to grow in the future market, it
is unavoidable to compete with 3G and acquire 3G’s customers.

Comparative study of various Generations
Table 2

SYSTEM KEY COMPONENTS OF 4G
a)System standards
 LTE Advanced
 WiMAX 2
b) Multiplexing and access schemes
OFDM+ MIMO
W–OFDM
 MC-CDMA
c) IPv6 SUPPORT
d) Advanced antenna systems
Multiple antenna technologies are used to achieve high rate, high reliability and long
communication range.
e) Software-defined radio (SDR)
Standards constituted by a 4G device can be realized using SDR.

Cont…
 System standards
 LTE
 Long Term Evolution (LTE) is a radio platform technology that will allow operators to
achieve even higher peak throughputs than HSPA+ in higher spectrum bandwidth.
 LTE uses Orthogonal Frequency Division Multiple Access (OFDMA) on the downlink,
which is well suited to achieve high peak data rates in high spectrum bandwidth.
7TH MOBILE
COMM
STANDARDSolution to Charging and Billing in 4G Network VIT

LTE capabilities include:
Downlink peak data rates up to 326 Mbps with 20 MHz bandwidth
Uplink peak data rates up to 86.4 Mbps with 20 MHz bandwidth
Operation in both TDD and FDD modes
Scalable bandwidth up to 20 MHz, covering 1.4 MHz, 3 MHz, 5 MHz, 10 MHz, 15 MHz,
and 20 MHz in the study phase
Reduced latency, up to 10 milliseconds (ms) round-trip times between user equipment
and the base station, and to less than 100 ms transition times from inactive to active

 System standards
 WiMAX 2
 WiMAX stands for Worldwide Interoperability for Microwave Access. WiMAX 2
also called Wireless MAN-Advanced has become the first true 4G technology to be
approved by the IEEE and ITU.
 The unique and excellent infrastructure of WiMAX is offering Ultra-Wideband and
providing range from 2 to 10 GHz and outstanding time response.
 This technology supports MIMO, femto cells, self-organizing networks & relays,
and multicarrier operation. It supports both 120Mbps downlink and 60Mbps uplink
speeds.

 Orthogonal frequency-division multiplexing (OFDM) is a frequency division
multiplexing (FDM) scheme that uses a digital multi-carrier modulation method.
 OFDM uses the spectrum more efficiently by making all the sub-carriers orthogonal to
one another, using fast Fourier transform (FFT) to prevent interference between the
closely spaced sub-carriers.
 In OFDM, the guard band is reduced by the orthogonal packing of the subcarriers,
improving the spectral efficiency .
 Since each carrier in an OFDM signal has a very narrow bandwidth (i.e. few kHz), the
resulting symbol rate is low.
 Due to the orthogonal nature of the modulation, these multiple sub-carriers overlap in
the frequency domain, but do not cause Inter-Carrier Interference (ICI).
 In OFDM, the guard band is reduced by the orthogonal packing of the subcarriers,
improving the spectral efficiency.

IPv6 SUPPORT
The IP address is based on IPv6
IPv4 X.X.X.X (32 bits)
Example: 216.37.129.9
IPv6 X.X.X.X.X.X (128 bits)
Example:
216.37.129.9 , 79.23.178.229 ,65.198.2.10 192.168.5.120
Home care of mobile Local network
Addres address IP address address

WIMAX
 Need for the extension of the range of Wi-Fi
 Key to Wi-Fi’s success:
1. Simple Time Division Duplex protocol and flat IP architecture.
2. Base station could be plugged into simple DSL line.
 Goal of WiMAX- to extend Wi-Fi like services to an entire community by using
inexpensive components and licensed or unlicensed frequencies.
 Roger Marks founded 802.16 (WiMAX) working group in 1998 and has chaired
the committee since then. WiMAX combines the cellular range with the Wi-Fi
speed. It plugs into Ethernet like Wi-Fi and provides roaming voice and data
like cellular.

WiMAX standards
 First wireless MAN air interface standard in 2001 (use above 10GHz)- approved
WiMAX 802.16a original WiMAX specs in January 2003 Followed by 802.16d (fixed
WiMAX) in 2004 which added the MIMO.
 Further came in 802.16e (mobile WiMAX) which added the mobility factor Current
version is 802.16j which added multihop relay
 Future standards of 802.16m, 802.16n and 802.16p are in progress which will bring
in advanced air interface with higher data rates of 100mbps for mobile and 1Gbps for
fixed services along with higher reliability of network and FDD along with TDD.

WiMAX specifications
 Distances up to 50kms (30 miles) for point to point(line of sight) communication
and up to 8kms (5miles) for point to multipoint (non line of sight) communication
 20MHz WiMAX channel - speeds of up to
75Mbps(theoretically) for users near the B.S. , practically only up to 45Mbps
 Frequency reuse and B.W. range from 1.5MHz to 20MHz.
 It uses licensed spectrum of : 2.3GHz, 2.5GHz and 3.5GHz as well as unlicensed
spectrum of 3.65GHz and 5.8GHz.

LTE explained
 LTE is a standard for wireless data communications technology and a development of
the GSM/UMTS standards.
 The goal of LTE was to increase the capacity and speed of wireless data networks
using new DSP (digital signal processing) techniques and modulations that were
developed around the turn of the millennium. A further goal was the redesign and
simplification of the network architecture to an IP-based system with significantly
reduced transfer latency compared to the 3G architecture.
 The LTE wireless interface is incompatible with 2G and 3G networks, so that it must be
operated on a separate wireless spectrum.
 Evolves form third generation technology based on WCDMA.
• Supports higher peak data rate through wider bandwidth.
• Provides Low Latency and Overhead (Radio Delay<5mSec)
• Implements Scheduling at Base station to maintain Channel Quality.
• All IP based network with reduction in cost per bit
• Flexibility in use of new and existing frequency bands (Spectrum Flexibility)
• Lower power consumption
• Supports mobility speeds up to 350km/hr with 500km/hr under consideration

LTE specifications:
 Higher Peak data rates(20MHz operation):
downlink: 100Mbps
(150Mbps peak based on 2x2 MIMO)
(300Mbps peak based on 4x4 MIMO)
uplink: 50Mbps(75Mbps peak) (5Mbps individually)
 Improved latency (UE-RNC-UE) below 10ms (round trip time)
 Support of scalable B.W. – 1.4,3,5,10,15,20MHz
 Support of paired and unpaired spectrum (FDD and TDD)
 Uplink: QPSK, 16-QAM and 64-QAM (optional for handset)
 Downlink: QPSK, 16-QAM and 64-QAM
 Uplink- SC-FDMA and Downlink- OFDMA

LTE architecture
 Provide open interface to support multi vendor deployments
 Provide robustness – no single point of failure
 Support Multi- RAT(Radio Access Technology) with resources controlled from the
network Support of seamless mobility to legacy systems as well as to other emerging
systems including Inter-RAT handover and service based RAT selection.
 Maintain appropriate level of security.
 LTE makes use of new e-NodeB’s and gets rid of the use of RNC.
 Simple network architecture with open interfaces`

LTE Architecture
Figure 2

 Needs for security and manageability
 4G system uses the Internet Protocol version 6 (IPv6) to locate devices.
 There is room for approximately 3.40 * 1038 unique addresses.
 There are enough addresses for every phone to have a unique address.
 Voice over Internet Protocol (VoIP) is a methodology and group of technologies for
the delivery of voice communications and multimedia sessions over Internet
Protocol (IP) networks

Technical performance Practical advantages of LTE
Higher bandwidth (data speeds).
 Low latency, lower idle-to-active times
(improved network responsiveness).
 High spectrum efficiency means
higher
network capacity, improved cost
efficiency.
 Backwards compatibility and future
proofing.
 Velocity tolerance.
 All IP network means easier
integration,
improved cost efficiency.
 Enhancements to security and Quality
of
Service.
Better speed of data uploads
and downloads
– Enabling use of richer/more
numerous data streams:
larger files, more quickly
 Improved responsiveness
allows real-time communication
 Improved performance from
fast-moving vehicles
Better reliability of (fast)
connection
Increased mobility
Improved application
performance Table 2Solution to Charging and Billing in 4G Network VIT

Compared with 3G Compared with Wi-Fi
More applications to be
used on mobile devices,
out of the home or office
Faster or real-time sharing
of large files and streaming
media
 Near-immediate delivery
of time-sensitive data,
such as for real-time interaction
or transactions
Fully-mobile use of applications
requiring true broadband speeds
 Improved convenience
(‘ownership’ of the mobile
connection)
Security (no need authenticate
onto another, possibly public,
network)
Practical advantages of 4G LTE over other
wireless technologies
Table 3

Advantages and Disadvantages:
 More affordable communication services.
 One device can communicate with all vs. many devices communicating with some
devices.
 TV, internet, phone, radio, home environment sensors all reachable through one device
and the cell phone`s Streaming video transfers.
 InterNet Accessing techniques through broadband and GPRS activated mobile access.
 Increase in social networking, invasion of privacy, security concerns
 Increase in regulation likely (i.e. no driving and using a cell phone)
 Supports for multimedia, voice, streaming video internet and other broadband services.
 IP based mobile system.
 Low cost, high capacity and low cost per bit.
 Gloabal access and portability and scalable mobile services.
 Seamless switching, and a variety of quality of service driven service.
 Better scheduling and call admission control techniques.
 Ad hoc and multi hop networks.
 Better spectral efficiency etc. for int
 Quickly download files over a wireless network.Solution to Charging and Billing in 4G Network VIT

CONT…..
 Extremely high voice quality
 Easily access Internet, IM, Social Networks, streaming media, video calling, etc.
 Higher bandwidth
 WiMAX, LTE, and HSPA+ are all versions of 4G, WiMAX is used by Sprint, LTE is
used by Verizon and AT&T, HSPA+ is used by AT&T and TMobile
 4G is 10 times faster than 3G.e multimedia
Disadvantages:-
 Expensive and hard to implement
 Bettery usage is more
 Needs complex hardware

Billing issue in 4G Network
 Billing in 4G has become much more complicated because of 4G networks.This is
mainly due to heterogeneity of 4G networks and the frequent interaction of service
providers.
 4G feature actually promises to provide a convergent architecture i.e wherever you
are the network will be available either of home service provider or different providers
but currently the 4G service providers are offering only 4G services to customers
because of the difficulty of billing between various providers.

CONT….
 As shown in above figure 4G network is able to support various networks which
includes fixed line services, cellular services, personal area networks, local area
networks etc.
 If such services are being provided then user must be able to use all these services
according to his requirement.
 Complexity is an issue in such network as how the billing structure will be formed for
a customer.

Proposed solution to Billing issue:
 According to papers studied regarding the billing issue in 4G network, the network operator
should be able to provide the convergent structure for the 4G customers.
 User who have activated 4G network on their cell phone should be able to use Internet
always which is the main aim of 4G network.
 Consider user is moving to a new destination where 4G service is unavailable to him in
such case the 4G phones must be able to scan different available network either his home
operator or different operator and the service should be provided to him.
 In some cases for ex: In a Big mall Free open Wi-Fi is provided to users then the 4G cell
phones must be able to scan this free network and activate it to the user’s cell phone and
during this period no Internet charges should be applicable to user.
 Therefore in this proposed solution initially the user is first activating 4G network on his cell
phone later if the user is travelling and there is no 4G network then the cell phone first
scans other available network i.e. it checks if there is 3G network available if not then it
checks if 2G network is available else it just provides the basic services to user i.e. call and
text.
 All this will be updated in Home Network Database and a single bill will be provided to user.
 The main part is all the above process will be done automatically no human intervention
will be required.
 Therefore user can enjoy all services without his intervention at any point after activating
4G plan.

Simulation Result:

Literature Survey
Reference Paper Year Of Publishing
Unified Billing-Realization of
convergent architecture
for charging and billing in 4G
networks
December 2011
4G Wireless Networks:
Opportunities and Challenges
AUGUST 2010
Trusted Convergence Operator – A
Conciliate Solution to Accounting,
Charging and Unified Billing in
4G Networks
October 2011

References :
1. 4G Wireless Video Communications By: Haohong Wang et al.
2. A Holistic Solution for Charging, Billing & Accounting in 4G Mobile Systems.
3. International Journal of Computer and Electrical Engineering, Vol. 3, No. 5,
October 2011.
4. http://google.co.in.
5. http://www.slideshare.net/CiscoSP360/comparison-of-lte-and-wimax
6. http://www.wimax.com/lte/why-the-wimax-vs-lte-battle-isnt-a-battle

4G convergent architecture

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