PROJECT REPORT ON

OPERATION & MAINTAINENCE OF RADIO ACCESS NETWORKS AND KPI’S IMPROVEMENT

Registration No-3060070070 Prog : B.TECH/M.TECH)ECE Section-RD67T1A34

Under the Guidance of

MS. NITIKA WADWA Mr VISHAL BHARMORIA

RAN MANAGER

Department Of Electronics and Communication Lovely School of Technology and Sciences

Lovely Professional University, Phagwara July – December 2010

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DECLARATION

I hereby declare that the project work entitled (“Mobile Switch(MSC)”) is an authentic

record of my own work carried out at (MCN Shimla) as requirements of Industry Internship

project for the award of degree of (B.TECH(HONS) ), Lovely Professional University,

Phagwara, under the guidance of (Mr.Harsharn Singh Pabla) and (Kalyan

Chakravarthi), during July to December 2010).

(Signature of student)

TARUN MANOHAR KAUNDAL

7060070048

Date:

Certified that the above statement made by the student is correct to the best of our knowledge and belief.

Mr. KALYAN CHAKRAVARTHI Mr.HARSHARN SINGH PABLA

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Acknowledgments:

It is impossible to acknowledge all those people who have had a major influence on the

conception and fruition of this project. To the best of my ability I shall attempt to do so. I would

like to thank Mr. vishal singh bharmoria and Mr. Praveen Sharma at AirTouch Communications

for reviewing and approving the manuscript for publication. I would also like to thank Mr.

divender sharma and who have reviewed and provided valuable suggestions on parts of the

manuscript. have tirelessly answered many of my questions regarding the implementation details

of an CDMA system. Furthermore, I would like to express my sincere appreciation to the special

group of RF and traffic engineers that I work with and who challenge me every day on the

engineering and operational details of a large and complex CDMA network.

This project report would not have been possible without my mendor Mr. vishal singh bharmoria

unselfish love, support, and understanding during the many months of writing. He has endured

my frustrations and shared in my delights. For his quiet and loving participation, I am so very

much grateful.

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INDEXS. NO. CONTENTS Page No.

1. Acknowledgement 2

2. Company Profile 3

3. Introduction to CDMA 9

4. CDMA 12

5. GSM Architecture 1 3

6. Base station subsystem (BSS) 14

7. Network system subsystem (NSS) 17

8. Mobile switching center (MSC) 17

9. Various Interfaces in GSM Architecture 23

10. Call processing 24

11. Signaling 27

12. CCS#7 Signaling 27

13. MNP Introduction 28

14. NPDB (Number Portability Database) 28

15. MNP In India 30

16 ACQ 30

17 Alarm Monitoring 39

18 Conclusion

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I. Organisation overview

Tata Teleservices Limited (TTSL)

Type Private

Industry Telecommunications

Founded Incorporated 1996

Headquarters Navi Mumbai , India

Key peopleMr. Ratan N. Tata (Chairman)

Anil Kumar Sardana(MD) Wireless

products Telephone,Internet,Television

Employees 350,000

Parent Tata Group

DivisionsTata Indicom (CDMA,Tata DoCoMo (GSM)

Virgin Mobile India (CDMA/GSM)

Website Tatateleservices.com

Himachal Pradesh - Shimla Hari Villa,

Mauza Chotta,Chotta Shimla,

Kasumpati Road,

Shimla,HP - 171009

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Tel No: 0177 - 6532011

Fax No: 0177 - 2624226

COMPANY PROFILE :

Communications is the Tata Group’s largest investment and the Group’s objective is to provide

end-to-end telecommunications solutions for business and residential customers across the nation,

and internationally. Tata Teleservices also has India’s largest branded telecom retail chain and is

the first service provider in the country to offer an online channel to offer post-paid mobile

connections in the country The Group’s communications activities are currently spread primarily

over four companies—Tata Teleservices Limited (TTSL) and its associate Tata Teleservices

(Maharashtra) Limited (TTML), Tata Communication (erstwhile VSNL) and Tata Sky. Together,

these companies cover the full range of communications services, including:

Telephony Services: Fixed and Mobile

Media and Entertainment Services: Satellite TV

Data Services: Leased Lines, Managed Data Networks, IP/MPLS VPN, Dial-up Internet,

Wi-Fi and Broadband

Value-Added Services: Mobile and Broadband Content/Applications, Calling Cards, Net

Telephony and Managed Services

Infrastructure Services: Submarine Cable Bandwidth, Terrestrial Fiber Network and

Satellite Earth Stations and VSAT Connectivity

Profile

Tata Teleservices (TTSL) spearheads the Tata group’s presence in the telecom sector.

Incorporated in 1996, the company was the first to launch CDMA mobile services in India with

the Andhra Pradesh circle.

Today, TTSL along with Tata Teleservices (Maharashtra) serves over 58 million customers in

over 4,10,000 towns and villages. With an ambitious rollout plan, both in existing circles and

across new circles, the company stands for world-class technology and user-friendly services in

22 circles. Today, Tata Teleservices Ltd, along with Tata Teleservices (Maharashtra) Ltd, serves

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over 36 million customers in more than 320,000 towns and villages across the country, with a

bouquet of telephony services encompassing Mobile Services, Wireless Desktop Phones, Public

Booth Telephony and Wireline Services. Other services include value-added services like Voice

Portal, Roaming, Post-paid Internet Services, Three-way Conferencing, Group Calling, Wi-Fi

Internet, USB Modem, Data Cards, Calling Card Services and Enterprise Services. Some of the

other products launched by the company include Pre-paid Wireless Desktop Phones, Public Phone

Booths, Mobile Handsets and Voice & Data Services such as BREW Games, Voice Portal,

Picture Messaging, Polyphonic Ring Tones, and Interactive Applications like news, cricket,

astrology, etc.1868.

Area of business

Having pioneered the CDMA 2000-1x technology platform in India, Tata Teleservices has

established a 3G-ready robust and reliable telecom infrastructure in partnership with

Motorola, Ericsson and Lucent. The company has also received the license from the

Department of Telecommunications to launch GSM services. With the launch planned for

2009, TTSL is on the threshold of emerging as a true-play dual technology telecom

operator.

In November 2008, Tata Teleservices entered into an agreement with Japanese telecom major

NTT DOCOMO, moving it closer to a pan-India dual network presence. The company also

recently announced a unique reverse equity swap strategic agreement between its fully-owned

telecom tower subsidiary, Wireless TT Info-Services, and Quippo Telecom Infrastructure — with

the combined entity kicking off operations with 18,000 towers, thereby becoming the largest

independent entity in this space.

Tata Teleservices Limited now also has a presence in the GSM space, through its joint venture

with NTT DOCOMO of Japan, and offers differentiated products and services under the TATA

DOCOMO brand name. TATA DOCOMO arises out of the Tata Group's strategic alliance with

Japanese telecom major NTT DOCOMO in November 2008. TATA DOCOMO has received a

pan-India license to operate GSM telecom services-and has also been allotted spectrum in 18

telecom Circles and will roll out its services shortly, starting with South India.

TATA DOCOMO marks a significant milestone in the Indian telecom landscape, as it stands to

redefine the very face of telecoms in India. Tokyo-based NTT DOCOMO is one of the world's

leading mobile operators-in the Japanese market, the company is the clear market leader, used by

over 50 per cent of the country's mobile phone users.

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Tata Teleservices is part of the INR Rs. 2, 51,543 Crore Tata Group that has over 80 companies,

over 3, 30,000 employees and more than 3.2 million shareholders. With a committed investment

of INR 36,000 Crore (US$ 7.5 billion) in Telecom (FY 2006), the Group has a formidable

presence across the telecom value chain.

Tata Teleservices spearheads the Group’s presence in the telecom sector. Incorporated in 1996,

Tata Teleservices was the first to launch CDMA mobile services in India with the Andhra Pradesh

circle.

Beginning with its acquisition of Hughes Telecom (India) Limited in December 2002 [now

renamed Tata Teleservices (Maharashtra) Limited], which provides services in the Mumbai and

Rest of Maharashtra telecom circles, the company has swung into expansion mode and currently

has a pan-India state-of-the-art network.

Having pioneered the CDMA 2000 technology platform in India, Tata Teleservices has

established a 3G-ready robust and reliable telecom infrastructure in partnership with Motorola,

Ericsson and Lucent. The company has also received the license from the Department of

Telecommunications to launch GSM services as well. With this launch set for early 2009, TTSL

is on the threshold of emerging as a true-play dual technology telecom operator.

In November 2008, Tata Teleservices entered into an agreement with Japanese telecom major

NTT DOCOMO, as part of which the Japanese company acquired a 26% stake in TTSL for USD

2.7 billion. The transaction marks a key step in the strategic evolution of Tata Teleservices, as it

moves towards a pan-India dual network presence. On a broader level, the transaction is also

expected to mark the beginning of a relationship of broader co-operation between Tata companies

and the Nippon Telegraph and Telephone Corporation (NTT).

Tata Teleservices’ bouquet of telephony services includes mobile services, wireless desktop

phones, public booth telephony and wireline services. Other services include value-added services

such as voice portal, roaming, post-paid Internet services, 3-way conferencing, group calling, Wi-

Fi Internet, USB Modem, data cards, calling card services and enterprise services.

Tata Teleservices Limited spearheads the Tata Group's presence in the telecom sector. The Tata

Group had revenues of around US $75 billion in financial year 2008-09, and includes over 90

companies, over 350,000 employees worldwide and more than 3.5 million shareholders.

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Incorporated in 1996, Tata Teleservices Limited is the pioneer of the CDMA 1x technology

platform in India. It has embarked on a growth path since the acquisition of Hughes Tele.com

(India) Ltd [renamed Tata Teleservices (Maharashtra) Limited] by the Tata Group in 2002. It

launched mobile operations in January 2005 under the brand Tata Indicom and today enjoys a

pan-India presence through existing operations in all of India's 22 telecom Circles. The company

is also the market leader in the fixed wireless telephony market with its brand Walky. The

company has recently introduced the brand Photon to provide a variety of options for wireless

mobile broadband access. The company's network has been rated as the 'Least Congested' in India

for last five consecutive quarters by the Telecom Regulatory Authority of India through

independent surveys.

II. Existing system

a) INTRODUCTION TO CDMA:-

Designers and planners of the communication systems are often concerned with the efficiency

with which the systems utilize the signal energy and bandwidth. In some cases, it is necessary for

the system to resist external interference, to operate at low spectral energy, to provide multiple

access capability without external control and secure channel not accessible to the outsiders.

Thus, it is sometimes unavoidable to sacrifice some of the efficiency in order to enhance these

features. Spread spectrum techniques allow accomplishing such objectives.

Bandwidth expansion in spread spectrum systems is achieved by using a function that is

independent of the message, thus it is more susceptible to white noise as opposed to other

communication techniques, such as FM and PCM. Spread spectrum techniques have other

applications that make it unique and useful. These applications include:

1. Anti-jam capability-particularly for narrow-band jamming.

2. Interference rejection.

3. Multiple-access capability.

4. Multi-path protection

5. Covert operation or low probability of intercept (LPI)

6. Secure communications.

7. Improved spectral efficiency-in special circumstances

8. Ranging

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CDMA is a wireless communications technology that uses the principle of spread spectrum

communication. The intent of CDMA technology is to provide increased bandwidth in a limited

frequency system, but has also other advantages including extended range and more secure

communications. In a CDMA system, a narrow-band message signal is multiplied by a spreading

signal, which is a pseudo-noise code sequence that has a rate much greater than the data rate of

the message. CDMA uses these code sequences as a means of distinguishing between individual

conversations. All users in the CDMA system use the same carrier frequency and may transmit

simultaneously.

CDMA is a driving technology behind the rapidly advancing personal communications industry.

Because of its greater bandwidth, efficiency, and multiple access capabilities, CDMA is becoming

a leading technology for relieving the spectrum congestion caused by the explosion in popularity

of cellular mobile phones, fixed wireless telephones, and wireless data terminals. Since becoming

an officially recognized digital cellular protocol,

CDMA stands for "Code Division Multiple Access." It is a form of spread-spectrum, an advanced

digital wireless transmission technique. Instead of using frequencies or time slots, as do

traditional technologies, it uses mathematical codes to transmit and distinguish between multiple

wireless conversations. Its bandwidth is much wider than that required for simple point-to-point

communications at the same data rate because it uses noise-like carrier waves to spread the

information contained in a signal of interest over a much greater bandwidth. However, because

the conversations taking place are distinguished by digital codes, many users can share the same

bandwidth simultaneously. The advanced methods used in commercial CDMA technology

improve capacity, coverage and voice quality, leading to a new generation of wireless

networks.The core idea that makes CDMA possible was first explained by Claude Shannon, a

Bell Labs research mathematician Shannon's work relates amount of information carried, channel

bandwidth, signal- to- noise- ratio, and detection error probability.

Wireless communication systems use E&M waves to transmit signals through their. When

subscribers share the same frequency they will create interference.

The amount of interference depends on what technical is used to reduce the interference.

The resource: frequency

The problem: interference

The solutions: multiple access techniques Support

Radio Access Network (RAN) 11

Architecture

The main purpose of the WCDMA Radio Access Network is to provide a connection between the

hand- set and the core network and to isolate all the radio issues from the core network. The

advantage is one core network supporting multiple access technologies. The Radio Base Station

handles the radio transmission and reception to/from the handset over the radio interface (Uu). It

is controlled from the Radio Network Controller via the Iub interface. One Radio Base Station

can h The Radio Network Controller is the node that controls all WCDMA Radio Access

Network functions. It connects the WCDMA Radio Access Network to the core network via the

Iu interface. There are two distinctroles for the RNC, to serve and to control. The Serving RNC

has overall control of the handset that is con- nected to WCDMA Radio Access Network. It

controls the connection on the Iu interface for the handset it terminates several protocols in the

contact between the handset and the WCDMA Radio Access Network.

andle one or more cells.

The WCDMA Radio Access Network consists of two types of nodes:

Radio Base Station (Node B)

Fig:- 2.1

The Controlling RNC has the overall control of a particular set of cells, and their associated base

stations. When a handset must use resources in a cell not controlled by its Serving RNC, the

Serving RNC must ask the Controlling RNC for those resources. This request is made via the Iur

interface, which connects the RNCs with each other. In this case, the Controlling RNC is

also said to be a Drift RNC for this particular handset. This kind of operation is primarily needed

provide soft handover throughout the network.

o Radio Access Bearers

The main service offered by WCDMA RAN is the Radio Access Bearer (RAB). To establish a

call connection between the handset and the base station a RAB is needed. Its characteristics are

different depending on what kind of service/information to be transported. The RAB carries the

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subscriber data between thehandset and the core network. It is composed of one or more Radio

Access Bearers between the handset and the Serving RNC, and one Iu bearer between the Serving

RNC and the core network. 3GPP has defined four different quality classes of

o Types of Radio access bearers

• Conversational (used for e.g. voice telephony)– low delay, strict ordering

• Streaming (used for e.g. watching a video clip) – moderate delay, strict ordering

• Interactive (used for e.g. web surfing)

• Background (used for e.g. file transfer) – no delay requirement

Both the Conversational and Streaming RABs require a certain reservation of resources in the net-

work, and are primarily meant for real-time services.They differ mainly in that the Streaming

RAB tolerates a higher delay, appropriate for one-way real-time services. The Interactive and

Background RABs are so called ‘best effort’, i.e. no resources are reserved and the

throughput depends on the load in the cell. The only difference is that the Interactive RAB provides

a priority mechanism. The RAB is characterized by certain Quality of Service (QoS) parameters,

such as bit rate and delay. The core network will select a RAB with appropriate QoS based on the

service request from the subscriber, and ask the RNC to provide such a RAB.

o Transport in WCDMA Radio Access Network

The WCDMA Radio Access Network nodes communicate with each other over a transport

network. The 3GPP specification provides a very clear split between radio related (WCDMA)

functionality and the transport technology, meaning that there is no particular bias toany

technology. The transport network is initially based on ATM, but IP will soon be included as an

option.

o Radio Interface Overview

The protocol stack of the radio interface between WCDMA Radio Access Network and the

handset consists of a number of protocol layers, each giving a specific service to the next layer

above. The main purpose with each layer is as follows

Layer 3: Signaling to control the connection to the handset.

Layer2: If there is time for it, to retransmit packetswhich has been received in error.

Layer 1: To transmit and receive data over the radio,including basic protection against bit errors.

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The Physical Layer (Layer 1) offers Tr a n s p o r t Channelsto the MAC layer. There are

different types of transport channels with different characteristics of the transmission. Common

transport channels can be shared by multiple handsets (e.g. FACH, RACH,

DSCH, BCH, PCH). Dedicated transport channels (DCH) are assigned to only one handset at a

time. The transmission functions of the physical layer include channel coding and interleaving,

multiplexing of transport channel mapping to physical channels, spreading,

modulation and power amplification, with The transmission functions of the physical layer

include channel coding and interleaving, multiplexing of transport channels, mapping to

physical channels,spreading, modulation and power amplification, with

corresponding functions for reception.

A frequency and a code characterize a physical channel. The specifications include two modes:

the FDD mode (Frequency Division Duplex) and the TDD mode (Time Division Duplex). The

FDD mode is the mainstream mode that operators are now deploying in WCDMA. The TDD

mode may eventually be de ployed as well, as a complement to the FDD mode. This doc-

ument does not describe the TDD mode.

Fig :-2.2

A radio access network (RAN) is part of a mobile Telecommunication system. It implements a

radio access technology. Conceptually, it sits between the Mobile phone, and the core network

(CN). The mobile phone is varyingly known as user equipment (UE), terminal equipment, mobile

station (MS), etc., depending on the standard.

Examples of radio access network types are:

GRAN - GSM radio access network

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GERAN - essentially the same as GRAN but specifying the inclusion of EDGE packet

radio services

UTRAN - UMTS radio access network

The term RAN is typically used in regards to the GSM, UMTS, and associated family of standards. While

there is no direct equivalent in TIA standards such as IS-136 and IS-95, the equivalent would be the air

interface of that network, coupled with those components governing the networking of base stations and

their connection to the core network.

Note that it is also possible for a single handset/phone to be simultaneously connected to multiple radio

access networks. Handsets capable of this are sometimes called dual-mode handsets. For instance it is

common today (2008) for handsets to support both GSM and UMTS (a.k.a. "3G") radio access

technologies. It is then possible to seamlessly transfer an ongoing call between different radio access

networks without the user noticing any disruption in service

See the following diagram :

CN

/ \

/ \

RAN RAN

/ \ / \

UE UE UE UE

Fig:-2.3.

o Introduction to kpi :-

Key Performance Indicators are quantifiable measurements, agreed to beforehand, that reflect the

critical success factors of an organization. They will differ depending on the organization. A

business may have as one of its Key Performance Indicators the percentage of its income that

comes from return customers. A school may focus its Key Performance Indicators on graduation

rates of its students. A Customer Service Department may have as one of its Key Performance

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Indicators, in line with overall company KPIs, percentage of customer calls answered in the first

minute. A Key Performance Indicator for a social service organization might be number of clients

assisted during the year.

Whatever Key Performance Indicators are selected, they must reflect the organization's goals,

they must be key to its success,and they must be quantifiable (measurable). Key Performance

Indicators usually are long-term considerations. The definition of what they are and how they are

measured do not change often. The goals for a particular Key Performance Indicator may change

as the organization's goals change, or as it gets closer to achieving a goal.

o Key Performance Indicators Reflect The Organizational Goals

An organization that has as one of its goals "to be the most profitable company in our industry"

will have Key Performance Indicators that measure profit and related fiscal measures. "Pre-tax

Profit" and "Shareholder Equity" will be among them. However, "Percent of Profit Contributed to

Community Causes" probably will not be one of its Key Performance Indicators. On the other

hand, a school is not concerned with making a profit, so its Key Performance Indicators will be

different. KPIs like "Graduation Rate" and "Success In Finding Employment After Graduation",

though different, accurately reflect the schools mission and goals.

o Background

The term KPI has become one of the most over-used and little understood terms in business development

and management. In theory it provides a series of measures against which internal managers and external

investors can judge the business and how it is likely to perform over the medium and long term.

Regrettably it has become confused with metrics – if we can measure it, it is a KPI. Against the growing

background of noise created by a welter of such KPI concepts the true value of the kpi become lost .The

KPI when properly developed should be provide all staff with clear goals and objectives, coupled with an

understanding of how they relate to the overall success of the organisation. Published internally and

continually referred to, they will also strengthen shared values and create common goals.

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o Features and Advantages of CDMA

CDMA has several unique features that make it a cost-effective, high quality wireless so

lution. In this module you will learn what those features are and how they provide advantages.

Features of CDMA

The following features are unique to CDMA technology:

Universal frequency reuse

Fast and accurate power control

Rake receiver

Different types of handoff

Frequency reuse

The frequency spectrum is a limited resource. Therefore, wireless telephony, like radio, must

reuse frequency assignments.

For example, two radio stations might transmit at 91.3 FM. There is no interference as long as

the radio stations are far enough apart.

Fig:- 2.4

CDMA frequency reuse planning

Each BTS in a CDMA network can use all available frequencies. Adjacent cells can transmit at

the same frequency because users are separated by code channels, not frequency channels.

This feature of CDMA, called "frequency reuse of one," eliminates the need for frequency

planning.

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o Advantages of CDMA

CDMA technology has numerous advantages including:

Coverage

Capacity

Clarity

Cost

Compatibility

Customer satisfaction

Coverage

CDMA's features result in coverage that is between 1.7 and 3 times that of TDMA:

Power control helps the network dynamically expand the coverage area.

Coding and interleaving provide the ability to cover a larger area for the same amount

of available power used in other systems.

Capacity

CDMA capacity is ten to twenty times that of analog systems, and it's up to four times that of

TDMA. Reasons for this include:

CDMA's universal frequency reuse

CDMA users are separated by codes, not frequencies

Maximized capacity.

b) EXISTING SOFTWARE:-

If we talk about the software part then it depends upon the case wether we are dealing with

switch or in monitoring. Software part used in following cases :-

Switching

Monitoring

Customer complaints

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In case of switching we used winfiol

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o Background

AXE switches can be managed using a Man-Machine-Language interface (MML).

At a first glance the interface is quite similar to a DOS or UNIX console in the means of

the capability to enter commands at a prompt and getting result printout in return.

The commands are called MML commands. Since there are a lot of MML commands

(>5000) with several options and there are many switches to manage, the first step was to

put the commands for a certain task into a file and send the command file as a batch job.

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After a while tools where developed to ease the use of the MML command interface.

WinFIOL was on of them.

WinFIOL introduced a simple scripting language to control the sending of the MML

commands.

WinFIOL is a family of tools specially designed to enable users to tap into the AXE

switches and unleash their full capabilities. WinFIOL runs on both Windows and Solaris.

On the UNIX platform a more complex script language was developed, AUTOSIS.

o Description

Technical

The objective of this thesis is to design a script parser for AUTOSIS and incorporate it with

WinFIOL.

The idea is to implement support for AUTOSIS script into WinFIOL in order to get the

ability to run AUTOSIS scripts from a Windows environment with the channel frame work that

WinFIOL offers.

WinFIOL has an interface that allows plug-ins so the script module will be quite isolated

from the main application.

A good design could also be used to develop support for other script languages into

WinFIOL.

The target project will be WinFIOL, which is a maintenance software for Ericsson AXE

telephone switches which runs on both Windows and Solaris.

A short investigation shall be made for alternative solutions of implementing the parser in

the range from “let’s invent it by our self’s” to use of lexical analysis tools and compiler

compilers.

The design and implementation of the script parser shall be made according to what is

decided after the investigation.

Why

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The Windows platform is now used by several operators. There is quite a large number of existing

AUTOSIS scripts in the world today. Enabling WinFIOL to support AUTOSIS would give it a

better position on the market.

Knowledge needed

• Experience from programming and scripting.

• Competence within object-based analysis and design, and experience with an object-oriented

programming language.

Knowledge desired

• Formal languages and automata theory

• Knowledge in principles of compiler design

In case of monitoring we used CNO2

ZXPOS CNO2(Mobile Communication Network Integrated Expert Office II) is a

network optimization & analysis software belonging to ZTE ZXPOS network plan and

optimization solution. Based on OMC data (CM、FM、PM、CDT etc.) CNO2 cooperates with

other ZXPOS software to give customer a comprehensive and powerful solution for network

planning, constructing, running and maintenance.

As a powerful optimization & analysis platform, it is accomplished in depth presentation,

analysis, drill of the network performance data and network running status. Robust nature and

flexible deployment together with user friendly nature ensures proper analysis and as a result the

optimization of the network becomes easier and faster.

The functions of CNO2 is classified to basic functions provided with ZTE OMC software and

advanced functions optional for meeting the needs of customers flexibly.

o Features:

　  •　  It is no need installing any client software, network optimizing on any computer at

anytime and anywhere: CNO2 is a web based enterprise application. It is constructed by

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browser/server three tiers structure and make customs access ease and quick. Customs are

dismissed any agony for client software’s installing and updating.

　  •　　High stability, retractility and expansibility: CNO2 is module structure designed, safe

and reliable, with powerful fault-tolerant & 7*24 hours running capability.

　   • 　 　 Multiple performance index system show the network comprehensive

performance: CNO2 offered a powerful CDMA network performance KPI index system(1X

RLSA、1XEV-DO and GoTa Indexes) to make customers evaluate network status from many

angles multi-layer stereoscopic.

　  •　　Offer abundant statistic and analyse function: Based on the powerful index system

and other kinds of running data,CNO2 offered powerful analysis tools such as basic statistics,

TopN analysis, Failure Reason analysis, CDT analysis etc. to speed the procedure of discovering

a problem and solving the problem.

　  •　　Flexible deploy mode: CNO2 can be deployed flexibly in ZTE OMM, LOMC, POMC

or be deployed independently. This flexibility will make the customer have more choices to

combine economical their hardware investment.

o Advantages:

　  •　　Standard real time collection of OMC data function: CNO2 provides standard real

time collection of OMC data. Data mapping and secondary preprocessing & calculating tech.

make the performance data capacity lower and speed the analysis procedures. Standard real time

collection of OMC data will also make the supervision of network performance possible.

　   •　　 Abundant performance data statistics and analysis method: diversified static

analysis and dynamic analysis methods corresponding to diversified performances of the network:

Multiple display modes such as Graph and Table.

　  •　　Powerful report forms builde function: CNO2 has a comprehensive integrated report

framework and container affording customers to create, manage, and deliver web-based reports.

Supports network index KPI and statistics template customization to satisfy vary user’s advanced

requirement for index system.

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　   •　　Problem analyse tools and trend forecast: CNO2 has a failure reason analysis tool

affording customers to inspect the inside world of the network and discover the details of

problem. Provide resource status of network analyse function, it can offer network resource

available and using status statistic.

　  •　　Powerful background wireless parameter query and checkout function:CNO2 can

query wireless parameter in appointed bound or aim at appointed type of network entity, these

parameter in the query result that can be checkout according to the value of a given standard.

Support customize NE(network element) group to attention the target NE group as keystone.

o Benefits:

　   •　　   Web mode is simple and convenient, user can inspect and control the status of

network, so user can adequately enjoy the feeling that network was in the best control.

　  •　　 Multiple predefined report forms template and report automatical output let user avoid

the labour that manual export report forms. Advance user’s input-output ratio.

　  •　　 Provide abundant and comprehensive KPI statistic, analyse and report methods, deep-

seated exposure and extrude all of the network problem, shorten the periods of detect and resolve

network problem.

 In case customer complaints we used oracle software.

Now product software development based on capability mutual model (cmm).all the phases of

software development were technically evaluated.

c) DFD for system

o Design stage:-

zte used the following software design methods to ensure software reliability.

Use structural andmodular programming.

Use error tolerance design.

Overall design , summary design and detailed design are based upon technical evaluation .

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Use walk-through check and colleague review to check code deficiency.

Rollbacj is available for core operation.

Provide flow controls.

Omc is able to detect the data inconsistency possibility with foreground devices. Data

synchronization can be performed manually or automatically.

Input data check for consistency.

III. Design

a) System design:-

Analog Information

Analog information is continuous and does not stop at discrete values. An example of analog

information is time. It is continuous and does not stop at specific points. An analog watch may

have a second-hand which does not jump from one second to the next, but continues around the

watch face without stopping.

Analog Signals

An analog signal is a continuous waveform which changes in accordance with the properties of

the information being represented.

Fig:- 3.1

Digital Information

Digital information is a set of discrete values. Time can also be represented digitally. However,

digital time would be represented by a watch which jumps from one minute to the next without

stopping at the seconds. In effect, such a digital watch is taking a sample of time at predefined

intervals.

25

Digital Signals

For mobile systems, digital signals may be considered to be sets of discrete waveforms.

Fig:-3.2

ADVANTAGES OF USING DIGITAL

Human speech is a form of analog information. It is continuous and changes in both frequency

(higher and lower pitches) and amplitude (whispering and shouting). At first, analog signals may

appear to be a better medium for carrying analog information such as speech. Analog information

is continuous and if it were to be represented by discrete samples of the information (digital

signal), then some information would be missing (like the seconds on the digital watch). An

analog signal would not miss any values as it too is continuous. All signals, analog and digital,

become distorted over distances.

In analog, the only solution to this is to amplify the signal. However, in doing so, the distortion is

also amplified. In digital, the signal can be completely regenerated as new, without the distortion.

Fig:-3.2

The problem with using digital signals to transfer analog information is that some information

will be missing due to the technique of taking samples. However, the more often the samples are

taken, the closer the resulting digital values will be to a true representation of the analog

information. Overall, if samples are taken often enough, digital signals provide a better quality for

transmission of analog information than analog signals.

26

o GATEWAY MSC (GMSC)

Gateway functionality enables an MSC to interrogate a HLR in order to route a mobile

terminating call. It is not used in calls from MSs to any terminal other than another MS. For

example, if a person connected to the PSTN wants to make a call to a GSM mobile subscriber,

then the PSTN exchange will access the GSM network by first connecting the call to a GMSC.

The GMSC requests call routing information from the HLR which provides information about

which MSC/VLR to route the call to. The same is true of a call from an MS to another MS.

o MESSAGE CENTER (MC)

MC FUNCTIONS

An MC may be added to a GSM network to provide one or more of the following

messaging services:

Voice mail

Fax mail

Short Message Service (SMS) text messages

SMS Cell Broadcast (SMSCB) text messages

Transcoder

The transcoder is responsible for transcoding the voice channel coding between the coding used

in the mobile network, and the coding used by the world's terrestrial circuit-switched network, the

Public Switched Telephone Network. Specifically, GSM uses a regular pulse excited-long term

prediction (RPE-LTP) coder for voice data between the mobile device and the BSS, but pulse

code modulation (A-law or μ-law standardized in ITU G.711) upstream of the BSS. RPE-LPC

coding results in a data rate for voice of 13 kbit/s where standard PCM coding results in 64 kbit/s.

Because of this change in data rate for the same voice call, the transcoder also has a buffering

function so that PCM 8-bit words can be recoded to construct GSM 20 ms traffic blocks.

27

Although transcoding (compressing/decompressing) functionality is defined as a base station

function by the relevant standards, there are several vendors which have implemented the solution

outside of the BSC. Some vendors have implemented it in a stand-alone rack using a proprietary

interface. In Siemens' and Nokia's architecture, the transcoder is an identifiable separate sub-

system which will normally be co-located with the MSC. In some of Ericsson's systems it is

integrated to the MSC rather than the BSC. The reason for these designs is that if the compression

of voice channels is done at the site of the MSC, the number of fixed transmission links between

the BSS and MSC can be reduced, decreasing network infrastructure costs.

This subsystem is also referred to as the transcoder and rate adaptation unit (TRAU). Some

networks use 32 kbit/s ADPCM on the terrestrial side of the network instead of 64 kbit/s PCM

and the TRAU converts accordingly. When the traffic is not voice but data such as fax or email,

the TRAU enables its rate adaptation unit function to give compatibility between the BSS and

MSC data rates.

Fig:-3.3

o BSS interfaces

Um

The air interface between the mobile station (MS) and the BTS. This interface uses LAPDm

protocol for signaling, to conduct call control, measurement reporting, handover, power control,

28

authentication, authorization, location update and so on. Traffic and signaling are sent in bursts of

0.577 ms at intervals of 4.615 ms, to form data blocks each 20 ms.

Abis

The interface between the BTS and BSC. Generally carried by a DS-1, ES-1, or E1 TDM circuit. Uses

TDM subchannels for traffic (TCH), LAPD protocol for BTS supervision and telecom signaling, and

carries synchronization from the BSC to the BTS and MS.

A

The interface between the BSC and MSC. It is used for carrying traffic channels and the BSSAP

user part of the SS7 stack. Although there are usually transcoding units between BSC and MSC,

the signaling communication takes place between these two ending points and the transcoder unit

doesn't touch the SS7 information, only the voice or CS data are transcoded or rate adapted.

Ater

The interface between the BSC and transcoder. It is a proprietary interface whose name depends

on the vendor (for example Ater by Nokia), it carries the A interface information from the BSC

leaving it untouched.

Gb

Connects the BSS to the SGSN in the GPRS core network.

Fig:-3.4

b) DETAILED DESIGN

o .CELLULAR ARCHITECTURE

29

CELL In a cellular radio system, the service area is divided into geographical units that

are represented as hexagonal (which are called cells).Each cell size varies depending upon

landscape. Each cell

Fig:-3.5

is served by its own radio and control equipment, which are located at the cell site. Each cell site

provides the radio connection between mobile units in its area and the rest of the network. The

cell sites are connected to the Mobile Switching Center (MSC) by trunks. Other trunks connect

the MSC to the public switched telephone network (PSTN).

Fig (3.5.): Mobile Telephone System Using A Cellular Architecture

CLUSTERS

A cluster is a group of cells. No channels are reused within a cluster.

o Advantage of cellular concept

30

INCREASED SYSTEM CAPACITY: For example: By dividing a metropolitan region into one

hundred different areas (cells) with low power transmitters using twelve.Conversations (channels)

each, the system capacity theoretically could be increased from twelve conversations-or voice

channels using one powerful Transmitter - to twelve hundred conversations using one hundred

low power transmitters.

FREQUENCY REUSE

Frequency reuse is the use of the same RF frequency repeatedly in the same general area in one

Fig :-3.6

cellular system. Each cell site is allocated a set of frequencies, or channels. Neighboring cells are

assigned different frequencies in order to avoid interference. Cell sites sufficiently far apart can

simultaneously use the same frequencies, which allows reuse of each frequency (channel) for

different calls many times in a given service area.Figure shows the Seven Cell Reuse Pattern and

Frequency Assignment (Omni directional Cells). Maximizing the number of times that each

channel can be reused in a service area is the key to efficient cellular system design. The more

times a channel can be reused in a given service area, the more calls the system can handle. Cell

sites employ low-power transmitters for that very reason: cell sites using the same channels can

be located closer together with negligible co-channel (same channel) interference.

The power transmitted by a cell is only large enough to communicate with mobile stations located

near the edge of the cell’s coverage area. In a start-up system, the radius of cell might be eight

miles-referred to as a large cell mature system, the radius of a Cell might be one mile or less—

referred to as a small cell.

31

Fig:-3.7

DUPLEX CHANNEL

Each cell phone uses two frequencies per call -- a duplex channel. A cell

phone is a full-duplex device. That means that you use one frequency for talking and a second,

separate frequency for listening. Both people on the call can talk at once.

Channels use a pair of frequencies for communication:

Fig(3.7): Cell Splitting

1. Forward Link, for transmitting from cell site.

2. Reverse Link, for cell site to receive calls from the users.

Fig(3.7): Basic Mobile Telephone Service Network

CELL PLANS

32

The objective of a cell plan is to cover the service area as economically as possible, while allowing for

maximum flexibility for future frequency reuse.

CELL SPLITINING

Cell splitting, the process of adding new cell sites between existing cell sites to form a grid of

smaller cells, provides still more radio channels to meet service demands. As a service area

becomes full of users, this approach of cell spli tting is used to split a single area into smaller

ones. In this way urban areas are split into as many areas as necessary in order to provide

acceptable service levels in heavy traffic regions, while larger, less expensive cells can be used to

cover remoter regions.

SECTORING

In the initial expansion stages, it is possible to add previously unallocated user channels to cells

that need more capacity. Adding new channels requires additional radios.And

associated RF equipment at the selected cell sites. A cell r

fig:- 3.8)

equiring more capacity also may be divided into sectors, each of which has a directional antenna

that radiates more power in some directions than in others.

Directional antennas are important tools in minimizing interference. Sectoring is normally done

with 120-degree directional antennas, where three transmit antennas are used to cover the full 360

degre Fig: Cell Sectoring With 120-degree Directional Antennas

o HANDOFF

Handoff is the passing of a call from one traffic channel to another traffic channel to provide

better servicehigher quality communication—to the mobile user. Conditions that can trigger a

33

handoff include poor signal strength and poor signal quality. Handoff is required to maintain a

call in progress as the mobile station passes from one cell site coverage area to another.

TYPES OF HANDOFFS

There are three basic types of handoff:-

1. Intra-cell handoff: Handoff within the same cell site.

2. Inter-cell handoff: Handoff between neighboring cell sites within the same MSC.

3. Inter-MSC handoff: Handoff between neighboring cell sites controlled by two different

cell sites in two different MSCs.

Fig:-3.9)

For all three types of handoff, the serving cell initiates the handoff by sending a Handoff Request

Message to the MSC. Included in the message is a list of optimal cell.

Site candidates to which the call may be switched. The MSC selects a candidate from the list and

initiates the handoff-related process. .

There are cases where the MSC will initiate a handoff without direction from the cell site, for the

purpose of traffic balancing or maintenance, such as to transfer all calls from a particular cell site

to another so that the cell site can be taken off-line for testing.

o Advantages of Hard Handoff

1. Continue the call beyond the current network.

2. Provide expanded service.

3. Reduce dropped calls.

4. Overlay and integration of new CDMA networks with the existing networks.

34

o CELL PHONE CODES

All cell phones have special codes associated with them. These codes are used to identify the

phone, the phone's owner and the service provider.

Electronic Serial Number (ESN) - a unique 32-bit number programmed into the phone

when it is manufactured

Mobile Identification Number (MIN) - a 10-digit number derived from your phone's

number

System Identification Code (SID) - a unique 5-digit number that is assigned to each

carrier

While the ESN is considered a permanent part of the phone, both the MIN and SID codes are

programmed into the phone when you purchase a service plan and have the phone activated.

O MOBILE UNITS

A mobile unit is a piece of wireless equipment that connects a user to a wireless telephone system

over a radio link. The mobile unit can be mounted inside a car, in which case it is usually called a

car telephone, or it can be contained in a small hand-held unit, often called a mobile or mobile

unit.A mobile unit always contains a control unit, a transceiver, and an antenna.

CLASSES OF THE MOBILE UNITS

Mobile units are classified according to the amount of power that they transmit. Three classes of

mobile units are available.

1. The Class I mobile unit can output up to 3 watts of power. This is the most powerful

mobile unit with the greatest range. The Class I mobile unit is called a vehicle-mounted mobile

unit. It is permanently mounted in a car and has an antenna attached to the car roof.

2. The Class II mobile unit can output up to 1.2 watts of power. This is called a transportable

mobile unit because it is stored in a bag that can be carried from place to place.

35

3. The Class III mobile unit can output up to 0.5 watts of power. This is called a portable

mobile unit because the equipment is contained in a unit small enough to be held in one hand and

easily carried from place to place.

o CDMA ARCHITECTURE:-

Fig:-3.10

o A CDMA network consists of the following components

Mobile station. The CDMA mobile station (or mobile phone) communicates with other

parts of the system through the base-station system.

Base station (BS). The base station (BS) handles the radio interface to the mobile station.

The base station is the radio equipment (transceivers and antennas)\

Base station controller (BSC). The BSC provides the control functions and physical links

between the MSC and BTS. It provides functions such as handover, cell configuration data and

control of RF power levels in base transceiver stations. A number of BSCs are served by a MSC.

Mobile switching center (MSC). The MSC performs the telephony switching functions

of the system. It also performs such functions as toll ticketing, network interfacing, common

channel signalling..

36

Home location register (HLR). The HLR database is used for storage and management

of subscriptions. The home location register stores permanent data about subscribers, including a

subscriber's service profile, location information, and activity status.

Visitor location register (VLR). The VLR database contains temporary information

about subscribers that is needed by the mobile services switching center (MSC) in order to service

visiting subscribers. When a mobile station roams into a new mobile services switching center

(MSC) area, the visitor location register (VLR) connected to that MSC will request data about the

mobile station from the HLR, reducing the need for interrogation of the home location register

(HLR).

Authentication center (AC). The AC provides authentication and encryption parameters

that verify the user's identity and ensure the confidentiality of each call. The authentication center

(AUC) also protects network operators from fraud.

Operation and administration (OAM). The OAM is the functional entity from which

the network operator monitors and controls the system. The purpose of operation and support

system is to offer support for centralized, regional, and local operational and maintenance

activities that are required for a CDMA network.

o Base Transceiver Station (BTS)

The BTS contains the RF components that provide the air interface for a particular cell. This is

the part of the GSM network which communicates with the MS. The antenna is included as part

of the BTS. The BTS network element consists of the hardware components, such as radios,

interface modules and antenna systems that provide the Air Interface between the BSS and the

MSs. The BTS provides radio channels (RF carriers) for a specific RF coverage area. The radio

channel is the communication link between the MSs within an RF coverage area and the BSS.

The BTS also has a limited amount of control functionality which reduces the amount of traffic

between the BTS and BSC.

37

Fig:-3.11

A base transceiver station (BTS) or cell site is a piece of equipment that facilitates

wireless communication between user equipment (UE) and a network. UEs are devices like

mobile phones (handsets), WLL phones, computers with wireless internet connectivity, WiFi and

WiMAX gadgets etc. The network can be that of any of the wireless communication technologies

like CDMA, CDMA, WLL, WAN, WiFi, WiMAX etc. BTS is also referred to as the radio base

station (RBS), node B (in 3G Networks) or, simply, the base station (BS). For discussion of the

LTE standard the abbreviation eNB for enhanced node B is widely used.

Though the term BTS can be applicable to any of the wireless communication standards, it

is generally and commonly associated with mobile communication technologies like CDMA and

CDMA. In this regard, a BTS forms part of the base station subsystem (BSS) developments for

system management. It may also have equipment for encrypting and decrypting communications,

spectrum filtering tools (band pass filters) etc. antennas may also be considered as components of

BTS in general sense as they facilitate the functioning of BTS. Typically a BTS will have several

transceivers (TRXs) which allow it to serve severaldifferent frequencies and different sectors of

the cell (in the case of sectorised base stations). A BTS is controlled by a parent base station

controller via the base station control function (BCF). The BCF is implemented as a discrete unit

or even incorporated in a TRX in compact base stations. The BCF provides an operations and

maintenance (O&M) connection to the network management system (NMS), and manages

operational states of each TRX, as well as software handling and alarm collection. The basic

structure and functions of the BTS remains the same regardless of the wireless technologies.

38

Fig:-3.12

A base transceiver station (BTS) or cell site is a piece of equipment that facilitates

wireless communication between user equipment (UE) and a network.

o General Architecture

A BTS in general has the following units:

Transceiver (TRX)

Quite widely referred to as the driver receiver (DRX). Basically does transmission and reception

of signals. Also does sending and reception of signals to/from higher network entities.

o Base station subsystem (BSS)

The base station subsystem (BSS) is the section of a traditional cellular telephone network which

is responsible for handling traffic and signaling between a mobile phone and the network

switching subsystem. The BSS carries out transcoding of speech channels, allocation of radio

channels to mobile phones, paging, transmission and reception over the air interface and many

other tasks related to the radio network

The base station subsystem (BSS) is the section of a traditional cellular telephone network which

is responsible for handling traffic and signaling between a mobile phone and the network

switching subsystem. The BSS carries out transcoding of speech channels, allocation of radio

39

channels to mobile phones, paging, transmission and reception over the air interface and many

other tasks related to the radio network

The Base Station system is responsible for all the radio related functions in the system, such as:

Radio communication with the mobile units

Handover of calls in progress between cells

Management of all radio network resources and cell configuration data.

ZTE ‘S BSS consists of two components:

Base Transceiver Station

Base Station Controller

o Base Station Controller (BSC)

The BSC is the functional entity within the CDMA architecture that is responsible for RR (Radio

Resource) allocation to a MS (Mobile Station), frequency administration and handover between BTS (Base

Transceiver Station) controlled by the BSC. The BSC function may be physically located with the BTS. If

this is the case there is no requirement for the Abis interface and a proprietary interface to map signalling

and traffic destined for the MS may be employed.

Fig:-3.13

o Base station controller

40

Fig:-3.14

Home location register (HLR)

The home location register (HLR) is a central database that contains details of each mobile phone

subscriber that is authorized to use the GSM core network. There can be several logical, and

physical, HLRs per public land mobile network (PLMN), though one international mobile

subscriber identity (IMSI)/MSISDN pair can be associated with only one logical HLR (which can

span several physical nodes) at a time.

The HLRs store details of every SIM card issued by the mobile phone operator. Each SIM has a

unique identifier called an IMSI which is the primary key to each HLR record.

The next important items of data associated with the SIM are the MSISDNs, which are the

telephone numbers used by mobile phones to make and receive calls. The primary MSISDN is the

number used for making and receiving voice calls and SMS, but it is possible for a SIM to have

other secondary MSISDNs associated with it for fax and data calls. Each MSISDN is also a

primary key to the HLR record. The HLR data is stored for as long as a subscriber remains with

the mobile phone operator.Examples of other data stored in the HLR against an IMSI record is:

GSM services that the subscriber has requested or been given.

GPRS settings to allow the subscriber to access packet services.

Current location of subscriber (VLR and serving GPRS support node/SGSN).

Call divert settings applicable for each associated MSISDN.

41

The HLR is a system which directly receives and processes MAP transactions and messages from

elements in the GSM network, for example, the location update messages received as mobile

phones roam around

o HLR FUNCTIONS

The HLR is a centralized network database that stores and manages all mobile subscriptions

belonging to a specific operator. It acts as a permanent store for a person’s subscription

information until that subscription is cancelled. The information stored includes:

Subscriber identity (i.e. IMSI, MSISDN)

Subscriber supplementary services

Subscriber location information (i.e. MSC service area)

Subscriber authentication information

Authentication centre (AUC)

The authentication centre (AUC) is a function to authenticate each SIM card that attempts to

connect to the GSM core network (typically when the phone is powered on). Once the

authentication is successful, the HLR is allowed to manage the SIM and services described above.

An encryption key is also generated that is subsequently used to encrypt all wireless

communications (voice, SMS, etc.) between the mobile phone and the GSM core network.

If the authentication fails, then no services are possible from that particular combination of SIM

card and mobile phone operator attempted. There is an additional form of identification check

performed on the serial number of the mobile phone described in the EIR section below, but this

is not relevant to the AUC processing.

The AUC does not engage directly in the authentication process, but instead generates data known

as triplets for the MSC to use during the procedure. The security of the process depends upon a

shared secret between the AUC and the SIM called the Ki. The Ki is securely burned into the SIM

during manufacture and is also securely replicated onto the AUC. This Ki is never transmitted

between the AUC and SIM, but is combined with the IMSI to produce a challenge/response for

identification purposes and an encryption key called Kc for use in over the air communications.

42

o AUC FUNCTIONS

The primary function of an AUC is to provide information which is then used by an

MSC/VLR to perform subscriber authentication and to establish ciphering procedures on

the radio link between the network and MSs

o Visitor location register (VLR)

The visitor location register is a temporary database of the subscribers who have roamed into the

particular area which it serves. Each base station in the network is served by exactly one VLR,

hence a subscriber cannot be present in more than one VLR at a time.The data stored in the VLR

has either been received from the HLR, or collected from the MS. In practice, for performance

reasons, most vendors integrate the VLR directly to the V-MSC and, where this is not done, the

VLR is very tightly linked with the MSC via a proprietary interface.

Data stored include:

IMSI (the subscriber's identity number).

Authentication data.

MSISDN (the subscriber's phone number).

CDMA services that the subscriber is allowed to access.

access point (GPRS) subscribed.

The HLR address of the subscriber.

VLR FUNCTIONS

The role of a VLR in a GSM network is to act as a temporary storage location for

subscription information for MSs which are within a particular MSC service area. Thus,

there is one VLR for each MSC service area. This means that the MSC does not have to

contact the HLR (which may be located in another country) every time the subscriber uses

a service or changes its status.

The following occurs when MSs move into a new service area:

The VLR checks its database to determine whether or not it has a record for the MS (based

on the subscriber’s IMSI).

When the VLR finds no record for the MS, it sends a request to the subscriber’s HLR for a

copy of the MS’s subscription.

43

The HLR passes the information to the VLR and updates its location information for the

subscriber. The HLR instructs the old VLR to delete the information it has on the MS.

The VLR stores its subscription information for the MS, including the latest location and status

o ROAMING

Mobile stations are constantly moving around in the cellular network. This action of

moving around and changing the “connection” over the air interface is called

ROAMING .If the mobile changes cells within the same Location Area (LA),as in case 1

in Figure 14-1, the network will QRW be updated. The most accurate location stored in

the VLR is the LA.If the mobile changes cells and the new cell is in a different LA, the

network must be informed. This process is called Location Updating type normal .The MS

knows that the “new” cell belongs to a different LA because when the MS is roaming it

listens to the BCCH carrier. (This is the frequency on which Broadcast Control

information is sent, see chapter “Air Interface”.) The BCCH broadcasts the current

Location Area Identity (LAI). The MS compares the last LAI received with the new LAI.

If they are the same, it means that the MS has not changed LAs and thus does not need to

inform the network. If the LAIs differ, it means that the MS has changed LAs and must

inform the network.

o PUBLIC LAND MOBILE NETWORK

Public Switched Network (PSTN)

The network that provides public telephone service. The portion of the total network that provides

the capability to interconnect any home or office in the country with any other.

Public Data Network (PDN)

Provides access to domestic and international data networks, including the public Internet .

Network system subsystem –NSS

Network switching subsystem (NSS) (or CDMA core network) is the component of a CDMA

system that carries out call switching and mobility management functions for mobile phones

roaming on the network of base stations. It is owned and deployed by mobile phone operators and

allows mobile devices to communicate with each other and telephones in the wider Public

Switched Telephone Network or (PSTN). The architecture contains specific features and

functions which are needed because the phones are not fixed in one location.

44

The NSS originally consisted of the circuit-switched core network, used for traditional CDMA

services such as voice calls, SMS, and circuit switched data calls. It was extended with an overlay

architecture to provide packet-switched data services known as the GPRS core network. This

allows mobile phones to have access to services such as WAP, MMS, and the Internet.

o Concepts of Signalling

CAS(common associated signalling )

CCS(common channel signalling)

Differences and Advantages (CAS & CCS)

Signaling can be defined as the exchange of information between call components required

to provide and maintain service e.g. Dialing digits, providing dial tone, accessing voice

mail, sending a call waiting tone, *69, etc.

Functions of Signaling

1. Supervisory Signaling

2. Address Signaling

3. Call Progress Signaling

1. Supervisory Signaling

:

Provides information on line or circuit condition

“It [signaling] informs a switch whether a circuit (internal to switch) or a

trunk (external to switch) is busy or idle; a called party is off-hook

or on-hook…”

Some supervisory signals:

Request for service - off-hook

Ready to receive address - dial tone

Call alerting – ringing

45

Call termination - on-hook

Request for operator - hook-switch flash

Called party station ringing - ring back

Network/called station busy - busy tone

2. Address Signaling

Directs and routes a telephone call to the called subscriber

If there is more than one switch involved in the call setup, signaling is

required between switches (inter register switching)

3. Call-Progress Signaling (Audible - Visible):Call Progress Signaling is

categorized by audio/visual signals sent in a forward and backward direction

Forward Direction: A signal sent to your phone which tells it to

ring

Backward Signaling:

Ring back - the distant telephone you are calling is ringing

Busy back - the called line is busy

ATB -All trunks are busy (sometimes voice announcement is used)

Loud Warble - Telephone is off hook

Signaling is basically having two types of interfaces UNI (User Network

Interface) and NNI (Network Network Interface) .Between the telephone and

the exchange we have UNI and between the exchanges we have NNI.

Fig:-3.15

UNI is classified as:

ASSS(Analog Subscriber Switching Signaling) PSTN /POTS

DSS 1 (Digital Switching Signaling 1 ) INSD

DSS 2 (Digital Switching Signaling 2 ) Broad band services

46

Exchange Exchange

NNI is classified as:

CAS (Channel associated signaling )

CCS7(common channel signaling system 7)

CHANNEL ASSOCIATED SIGNALING(CAS)

In case of CAS a dedicated signalling link is required for each speech channel and

Inter-exchange signal consists of both Line signal and register signals.

Line signal indicates basic state of a trunk

Register signal consists of the address information, stored in the register

and passed from one exchange to other.

The dedicated link provided for each speech channel is used to convey the

line signals. CAS in PCM system consists of 32 channels, from which 1 channel is

for Synchronization, 1 channel for signalling and rest of the 30 Channels are used

for voice and control. In 2.048 Mbps link between two exchanges 30 Channel

PCM link is used, Time slot 16 is used for line signal and remaining channels for

carrying address information as well as traffic. The 0 th channel is for

synchronization and the 16th channel for signalling only.

CHANNEL ASSOCIATED SIGNALING(fig:-3.16)

There are some limitations of CAS:

CAS is slow resulting in Longer Call setup times

Register Signals can be transferred only at the time of call setup

No possibility of 47ignalling during the talking phase of the call

Speech and Signaling path are same

COMMON CHANNEL SIGNALING (CCS)

47

CCS provides efficient 48ignalling system with much shorter call setup time and

enhanced Call control. In case of CCS only one timeslot is required for carrying Signaling

information of large number of circuits. One 48ignalling time slot can handle 1000 traffic

channels

In common channel 48ignalling the 0th time slot is reserved for synchronization and the 16th

time slot is reserved for 48ignalling and control both, the rest of the time slots are

dedicatedly voice channels. It is because of the 16th slot which is for 48ignalling, that

whenever one of the subscriber keeps the receiver down the circuit is released

automatically.

In case of CAS until or unless both the received party and the calling party keeps the

receiver down the circuit was not released. SS7 is a CCS type of 48ignalling and is mostly

used these days in all the telecommunication systems. A 48ignalling through one channel

can support nearly 30 E1 or PCM cable

COMMON CHANNEL SIGNALING (fig:-3.17)

o Mobile switching center(MSC)

The mobile switching center (MSC) is the primary service delivery node for CDMA/CDMA,

responsible for routing voice calls and SMS as well as other services (such as conference calls,

FAX and circuit switched data). The MSC sets up and releases the end-to-end connection, handles

mobility and hand-over requirements during the call and takes care of charging and real time pre-

paid account monitoring. In the CDMA mobile phone system, in contrast with earlier analogue

services, fax and data information is sent directly digitally encoded to the MSC. Only at the MSC

is this re-coded into an "analogue" signal (although actually this will almost certainly mean sound

encoded digitally as PCM signal in a 64-kbit/s timeslot, known as a DS0 in America).

48

There are various different names for MSCs in different contexts which reflects their complex

role in the network, all of these terms though could refer to the same MSC, but doing different

things at different times.

The gateway MSC (G-MSC) is the MSC that determines which visited MSC the subscriber who

is being called is currently located. It also interfaces with the PSTN. All mobile to mobile calls

and PSTN to mobile calls are routed through a G-MSC. The term is only valid in the context of

one call since any MSC may provide both the gateway function and the Visited MSC function,

however, some manufacturers design dedicated high capacity MSCs which do not have any BSS

connected to them. These MSCs will then be the Gateway MSC for many of the calls they handle.

The visited MSC (V-MSC) is the MSC where a customer is currently located. The VLR

associated with this MSC will have the subscriber's data in it

Fig:- 3.18

49

SwitchingTrafficI/F

TrafficI/F

Timing

O&M

CentralProcessing

BSS

BSC

RBS

RBS

RBS

ServiceNodes

PDN

PSTN

Core Function of MSC

The anchor MSC is the MSC from which a handover has been initiated. The target

MSC is the MSC toward which a Handover should take place.

o Other network elements connected to the MSC

The home location register (HLR) for obtaining data about the SIM and mobile services

ISDN number (MSISDN; i.e., the telephone number).

The base station subsystem which handles the radio communication with mobile phones.

The UMTS terrestrial radio access network (UTRAN) which handles the radio

communication with 3G mobile phones.

The visitor location register(VLR) for determining where other mobile subscribers are

located.

Other MSCs for procedures such as handover.

Tasks of the MSC include:

Delivering calls to subscribers as they arrive based on information from the VLR.

Connecting outgoing calls to other mobile subscribers or the PSTN.

Delivering SMSs from subscribers to the short message service centre(SMSC) and vice

versa.

Arranging handovers from BSC to BSC.

Carrying out handovers from this MSC to another.

Supporting supplementary services such as conference calls or call hold.

Generating billing information.

Processes include interfacing, switching, call setup & tear down and charging.

MSC is responsible for:

o Routing of calls

o Switching of calls

o Charging

o Billing

o Subscriber data base

o Roaming

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Fig:-3.17

d) DESIGN CODES:-

Two kinds of codes

CDMA uses two important types of codes to channelize users. Walsh codes channelize users on

the forward link (BTS to mobile). Pseudorandom Noise (PN) codes channelize users on the

reverse link (mobile to BTS).

(1) Walsh codes

Walsh codes provide a means to uniquely identify each user on the forward link. Walsh codes

have a unique mathematical property--they are "orthogonal."

In other words, Walsh codes are unique enough that the voice data can only be recovered by a

receiver applying the same Walsh code. All other signals are discarded as background noise.

51

PN codes

Pseudorandom Noise (PN) codes uniquely identify users on the reverse link.

A PN code is one that appears to be random, but isn't. The PN codes used in CDMA yield about

4.4 trillion combinations of code. This is a key reason why CDMA is so secure.

Code channels used in CDMA

A code channel is a stream of data designated for a specific use or person. This channel may be

voice data or overhead control data.

Channels are separated by codes.

The forward and reverse links use different types of channels.

Fig:- 3.18

FREQUENCY SPECTRUM

Spectrum Requirement

CDMA Carrier Bandwidth = 1.23 MHz

Guard Band=0.27 MHz on either side

CDMA Channel Band:

Forward Link-869 –894 MHz

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Reverse Link-824 –849 MHz

Frequency Calculations:

Transmitter Channel No. Frequency

Mobile1<=N<=866.03N + 825 MHz

Cell Site1<=N<=866.03N + 870 MHz

c) TESTING:-

a. Structural testing:-

Cabinet installation check :-

Ensure that cabinet installation location complies with the engineering design drawing .

Erect cabinet firmly that must resist an earthquake measuring up to 7.0 on richter scale.

Ensure that horizontal and vertically error and the gap between adjacent bases is lessthan

0.12 inch(3mm).

Ensure all others equipment and cabinet front door are in one line.

Ensure cabinet front and rear parts are at the distance of 31.50inch and 1.97inch away

from the walls respectively.

Ensure that all cabinetsparts are fixed properly.

Trunk and rf cables testing:-

Trunk cable connectors are properly installed , labelled and are not loose.

Cable shell is properly connected with grounding system.

Rf cable between modules in cabinet are properly connected.

Unused rf connectors are screwed on with a matching terminal.

Antenna installation check

Antenna support and tower are properly installed.

Antenna model is according to networking planning design.

Actual hanging height of an antenna is accordin to network planning design.

Rf and gps antennas are included in the protection area of a lightiniing rod.

Azimuth of antenna is according to network planning.azimuth error of directional antenna

is no more then 5degree.

53

Actual mechanical down tilt of an antenna is according to network planning and two uni-

polarization antennas have same down tilts.

All antenna poles are firmly installed are properly grounded. Vertical error is less than

2degree.

An omni-directional antenna is at least 59.05 inch (1.5m) away from the tower while a

directional antenna is aat least 39.37 inch away from the tower.

During installing an omni_directional antenna on a roof , horizontal interval between

omni-antenna and antenna lightning rod is not less than 98.42inch (2.5m).

An omni directional antenna is not installed in blind area.

Gps spatial angle is more than 90degree.

Feeder SWR check

Related to voltages standing wave ratio(vswr) value is specified and a vswr test diagram is

available.

½” indoor jumper terminal is connected with an swr tester for testing . SWR should be less than

1.5.

IV. Implementation:-

o Implementation of the project:-

My project is based upon operation and maintainence of radio accesss network and kpi

improvement . Actually these all related to the RF field. This is the main part during

transmission . A radio access network (RAN) is part of a mobile Telecommunication system. It

implements a radio access technology. Conceptually, it sits between the Mobile phone, and

the core network (CN). The mobile phone is varyingly known as user equipment (UE), terminal

equipment.

Examples of radio access network types are:

GRAN - GSM radio access network

GERAN - essentially the same as GRAN but specifying the inclusion of EDGE packet

radio services

UTRAN - UMTS radio access network

54

The term RAN is typically used in regards to the GSM, UMTS, and associated family of

standards. While there is no direct equivalent in TIAstandards such as IS-136 and IS-95, the

equivalent would be the air interface of that network, coupled with those components governing

the networking of base stations and their connection to the core network.

Note that it is also possible for a single handset/phone to be simultaneously connected to multiple

radio access networks. Handsets capable of this are sometimes called dual-mode handsets. For

instance it is common today (2008) for handsets to support both GSM and UMTS (a.k.a. "3G")

radio access technologies. It is then possible to seamlessly transfer an ongoing call between

different radio access networks without the user noticing any disruption in service.

d) Optimize the Radio Access Network

A radio access network helps mobile network operators meet the challenges of the increasing

bandwidth demands of third-generation (3G) mobile applications. With a radio access network,

operators can also support legacy services and reduce cost per bit.

Cisco offers a next-generation radio access network portfolio highlighted by Cisco Mobile

Transport over Pseudowires (MToP) technology. Using Cisco Radio Access Network solutions,

operators can:

Collapse all backhaul technologies onto a single IP/MPLS network

Easily scale services to one million triple-play subscribers and 2,700 mobile base stations

Rapidly provision bandwidth to support new services

Transparently support 2G, 3G, and 4G radio technologies

Take advantage of alternative transport media (such as Ethernet and DSL) for additional

cost savings

Achieve carrier-class IP security.

THE below is picture of ZTE BTS :

It means it is the main part of the tower and transmission process

It consist of

CTU PSU - power supply UNIT for the BTS

Control card

Alarm card

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Fig:- 4.1

e) CDMA BASICS

RADIO CHANNEL

A mobile station communicates with a base station via a radio channel. A radio channel is a bi-

directional radio transmission path. Each radio channel has two distinct frequencies; one for

downlink and one for uplink.

Downlink is defined as the transmission path from the base station to the mobile station, while

uplink is defined as the transmission path from the mobile station to the base station..

Fig:-4.2

Uplink and downlink on a radio channel

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The base station transmits on one frequency while the mobile station transmits on another

frequency. This creates a full duplex communication path. That is, simultaneous communication

in both directions.

FREQUENCY SPECTRUM

Different frequency bands are used for CDMA 900, CDMA 1800 and CDMA 1900. An operator

applies for the available frequencies or, as in the United States; the operator buys frequency bands

at an auction

For CDMA 900 the available frequency bands are:

Uplink 890 - 915 MHz

Downlink 935 - 960 MHz

For CDMA 1800 the frequency bands are:

Uplink 1710 - 1785 MHz

Downlink 1805 - 1880 MHz

For CDMA 1900 the frequency bands are:

Uplink 1850 - 1910 MHz

Downlink 1930 - 1990 MHz

o TERMINOLOGY

DUPLEX DISTANCE

The distance between one uplink frequency and its corresponding downlink frequency is called

the duplex distance. The duplex distance varies for different frequency bands, refer to Table

below:

57

Duplex distance

o Software maintainence:-

For the maintainence of software we have to check regular that there is no virus in our pc’s or

client .But in the omc rooms (from where all the operation is maintain or control) all the pc’s are

prevented by their administrative block. Because all the cpu’s or engineers laptops are strictly

prohibited to insert the pen derives etc or we can say that these all type of condition are blocked

by their IT department. If they want to make use of their pendrives port then have to take

permission firsr from their IT department.

o OSS (OPERATION & SUPPORT SYSTEM)

Working With Alarms:-

Alarms are generated when a failure or fault is detected in a network device.

Alarms generated are displayed in the alarm viewer.

Alarm viewer provides a range of functions for extracting information from alarms.

Alarm details include a brief description of device which has failed.

ALARM MONITORING

Alarm Monitoring: This is the prime function, which continuously monitors the alarm reported by

all BTS's, BSCs, MSC and other elements. It gives an audible alarm for pre-set alarm conditions.

Alarms for field sites (BTS’s and BSCs) also include environmental alarms, which are must for

field located sites as these are in cabins and rooms which have supporting accessories like power,

air cons, and fire hazards, security problems, since it is not possible to man hundreds of fields

locates sites for these types of issues, so these alarms are also reported to at the OMCR form

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where again these are reported back to the site engineers and technicians for suitable action to be

taken to remove them

Alarm WINDOW

Fig:-4.3

MONITORING OF EXTERNAL ALARMS OF BTS & NODES

The primary responsibility in Operation & Maintenance Centre was monitoring of alarms of BTS

and different nodes like MSC, BSC, TRC, HLR, GMSC etc.

At that time Operation & Maintenance Centre, Mohali was monitoring four different regions i.e.

Punjab, Haryana, Himachal Pradesh, Jammu & Kashmir. AIRTEL was having about 1050 BTS

sites in Punjab, 600 in Haryana, 350 in Himachal Pradesh, 200 in Jammu & Kashmir, 9 MSCs, 4

HLRs, 30 BSCs, 3 GMSCs etc.

These external alarms were monitored on Alarm Log Viewer and were escalated to responsible

engineer.

o External Alarms of BTS

1. Door open.

2. Fire/smoke.

3. Temperature high.

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4. Mains fail.

5. DG on.

6. DG fails to stop.

7. DG fails to start.

8. LLOP ( Low Lubricant Oil Pressure )

9. Fuel level low.

10. AC1 faulty.

11. AC2 faulty.

12. Rectifier fail.

13. Battery voltage low.

14. Both AC Faulty.

External Alarms of Nodes

1. Power alarm

2. Restart of nodes

3. Blocking of devices, routes, nodes etc

4. Digital interface path fault

5. CP, RP, AP faults

6. Software Fault

These external alarms can also be monitored by Command Handling Tool. All external alarms are

categorized into three categories: A1, A2, A3 depending upon the extent to which these alarms

effect the services.

In Command Handling Tool the particular node is connected and command used for printout of

alarms is:

Op:alarm,all

and after that SAVE AS

FAULT MANAGEMENT RELATED TO BTS

Check configuration of cell

op: cell<RCS ID>,extern

RCS ID means cell site ID

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This command prints out supervision of logical channels availability data for the sub cells of the

specified cell.

To get configuration of particular cell, this commands gives channels used i.e. No. of BCCH,

TCH and SDCCH.

Configuration of cell = no. of TRX used

= {BCCH+SDCCH+ (TCH/8)}/3

LVA (Limit Value Availability) value indicates the original defined value of TCH, SDCCH and

BCCH. NCH value indicates the present number of channels available.

FAULT MANAGEMENT

The Fault Manager system receives alarms from objects in the supervised telecommunications

networks, translates the alarm information to a standard format and logs the alarms. The figure

below outlines this process. The Alarm List Viewer allows you to do the following:

View alarm details

Acknowledge observation of the alarms

Add personal comments to the alarms

Clear alarms manually

Print, store, mail and copy the alarm information

Take LOGS of the Commands.

Fault Management comprises of following parts:

Alarm List Viewer

Alarm Log Browser

Alarm List Viewer is used for:

Viewing alarms

Viewing alarm details

Viewing related alarms

Acknowledging observation of the alarms

Adding personal comments to the alarms

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Clearing alarms manually

Printing, storing, mailing and copying the alarm information

Starting other functions

Example: Configuring the Alarm List Viewer window

Example: Viewing Cleared Alarms Only

Fig:-4.4

ALV Operating Process

Alarm Log Browser is used to search, view & save logs for particular sites for the past few hours

or any date. This helps in analysing the errors & those alarms that are generated frequently. The

Alarm Log Browser receives the values of the following attributes of the selected alarms:

Object of Reference

Perceived Severity

Event Type

Probable Cause

o OMCR CONNECTIVITY IN HIMACHAL

FEW SCREEN SHOTS OF ZTE ZXG 10

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Fig:-4.5

Fig:-4.6

V. Project Legacy

a) Current status of the project:-

63

The main and maximium part of this project i have covered .The technical things related to this project i

have covered durin my site visit and during the installation of new connection to some companies and in

my tata BSC and MSC.

And now i don’t think that something is missing in this project because i have attended all the visit during

my project related activities. And if we think that day by day new updates come .but the basic thing i

covered in this project which give me a great support during my viva, presentation and moreover during

m placement activities.

b) Technical and managerial lessons learnt:-

If we talk about the technical support then i can say that i got lot of knowledge practically and verbally

both. I often visit the site with my tata engineers and always try to get knowledge about the hardware and

bts stations.In omc room i done activities related to monitoring which means to say alarm monitoring .In

this we come to knoe which site is down and what type of error is running recently . In this way i come to

know about the errors which we face during the telecommunication and by this i can easily make

commands on the errors so that in future if there is any alarm then i can tell easily what type of problem

is running right now.

And if we talk about the managerical sklls then that thing also i got most . I come to know how i can

handle the situation , improved my circle with some engineers wether it is from TATA , AIRTEL .OR

RELIANCE. I come to know how we can make the better understanding with organisation memmbers .

because when we go outside only this is the thing which help us a lot in the settlement .

o EXTRA WORKING PROJECT

I have recently worked upon the project MOBILE NO. PORTABILITY .it is goin to launch in INDIA

before 25th jan 2011 .

o MOBILE NUMBER PORTABILITY (MNP)

MNP INTRODUCTION

Mobile Number portability (MNP) enables mobile subscribers to change their service providers or

their location without having to change their existing phone numbers. If the subscribers are not

satisfied with the services of their service provider, they can change their service provider while

retaining the existing phone number. This infuses competition among service providers and forces

them to improve their service standards to check subscriber churn. Many countries have made

number portability mandatory to liberalize competition. Many others are in the process of

implementing it. A significant technical aspect of implementing number portability is related to

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the routing of calls or mobile messages (SMS, MMS) to a number once it is ported to some other

network. The international and European standard is for a customer wishing to port his/her

number to contact the new provider (Recipient) who will then arrange necessary process with the

old provider (Donor). This is also known as 'Recipient-Led' porting. The UK is the only country

to not implement a Recipient-Led system, where a customer wishing to port his/her number is

required to contact the Donor to obtain a Porting authorization code (PAC) which he/she then has

to give to the Recipient. Once having received the PAC the Recipient continues the port process

by contacting the Donor. This form of porting is also known as 'Donor-Led' and has been

criticised by some industry analysts as being inefficient. It has also been observed that it may act

as a customer deterrent as well as allowing the Donor an opportunity of 'winning-back' the

customer.

o TYPES OF NUMBER PORTIBILITY

The various types of number portability are:.

Service Provider Number Portability: Subscribers can change the service provider while

retaining the same phone number. It is also called operator portability.

Location Number Portability: Subscribers can change their service location while keeping

the same telephone number.

Service Portability: Subscribers can change the subscribed services while retaining the same

telephone number. Service portability allows the subscribers to enjoy the subscribed services

in the same way when they roam outside their home NETWORK

Before we discuss the technical aspects and various call routing schemes in detail, let us

understand some terms in the context of mobile network and number portability.

Donor Network: It is the network that first assigns a telephone number to a subscriber.

Recipient Network: It is the network that currently serves the ported number. A recipient

network is a network that a subscriber’s number is ported to when the subscriber switches

the service provider.

Old Serving Network: The old serving network is the network that previously served the

ported number before the number was ported to the new serving network. Since a

subscriber can switch service provider any number of times, the old SP is not necessarily

the same as the donor network.

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Participant: A Participant is a service provider who is not related to the porting process in

any way and still needs the routing information for call routing and various other

activities.

There are two fundamental issues that need to be considered in implementing number portability

in a country.

o Number Porting Process: This applies to the policies and processes for porting the

numbers.

1) ORIGINATES A CALL

2) SRI(MSISDN)

3)SRI ACK(LRN+MSISDN)

4) ) IAM(LRN+MSISDN)

5) IAM(LRN+MSISDN)

6) SRI (MSISDN)

7) SRI (MSISDN)

8) SRI ACK(MSRN)

9) SRI ACK(MSRN)

10) IAM(MSRN)

o NUMBER PORTIBILITY DATABASE

The number portability database contains the routing information necessary to support number

portability. This database is designed to receive information from both the incumbent and new

service providers, validate the information received, and download the new routing information

when an activate message is received indicating that the customer has been physically connected

to the new service provider’s network. The NPDB provides the association between the called

party and the carrier LRN, identifying the switch to which the call should be routed. The NPDB

stores all ported numbers within the ported domain. Carriers can choose between two different

LNP database architectures for accessing the LRN associated with a particular directory number:

an integrated STP/SCP configuration or an STP with an adjunct SCP. An LNP SCP provides the

LRN for a particular directory number. The correct routing information for SCP-based services,

including line information database(LIDB), calling name delivery (CNAM), custom local area

signaling services(CLASS), and inter-switch voice messaging (ISVM) for a ported directory

number, is determined by 10-digit global title translation (GTT), also provided in the NPDB. The

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SCP is a high-transaction-oriented server that receives intelligent network(IN) and advanced

intelligent network (AIN) 0.1 LNP Transactional Capabilities Application Part (TCAP) messages

or Number Portability Request (NPREQ)messages from the SSPs/MSCs using the SS7 network.

As an alternative, some providers deploy an integrated STP/SCP platform, which enables high

transaction rates but requires fewer infrastructures (links and ports).The NPDB is not involved in

real-time call processing. The NPDB provides management, administration, oversight, and

integration of NPDB operations, hardware and software development, and all maintenance-related

functions.

MNP IN INDIA

• Out of several types of number portability DoT has recommended Mobile Number Portability

(MNP) for all mobile service operators.

• Two central clearing houses for MNP database covering North-West zone (Syniverse) and

South-East zone (Telecordia).

• These CCH will download the MNP database in operators NPDB on daily basis.

• MNP will be restricted only for intra circle operators.

• MNP will be allowed between CDMA and GSM operators.

• ACQ (All Call Query) direct routing method to implement MNP.

• Break before make porting process with negotiation period of

max 2 days and service interruption of max 30 minutes.

(ACQ) All call query- Direct routing method

The Originating Network receives a call from the caller and sends a query to a centrally

administered Number Portability Database (NPDB) also called central database (CDB).Network

operators generally keep local copies of the CDB, which is hosted on either a network element

within their network or a third party network element. The NPDB returns the routing information

of the dialed number. Based on the prefix(LRN) the Originating n/w will route the call to the

recipient n/w without involving the Donor network

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NPDB

ORIGINATING NETWORK

DONOR NETWORK

RECEIPIENT NETWORK

Fig:5.1

QUERY ON RELEASE

The Originating Network receives a call from the caller and routes the call to the donor network.

The donor network releases the call and indicates that the dialed number has been ported out of

that network.

The Originating Network sends a query to its copy of the centrally administered NPDB.

The NPDB returns the routing information of the dialed number.

The Originating Network uses the routing information to route the call to the new serving network

3 4 2 1

5

Fig:-5.2

NUMBER PORTING PROCESS

There are two approaches by which the number porting database can be maintained and

implemented i.e. Peer-to-Peer approach & Centralized approach

Peer-to-Peer approach

In this approach, there is a bilateral agreement between twoservice providers. The two service

providers agree on theimplementation of number portability based on proprietary interface. With

this non-standard approach, there can be multiplecommercial agreements between the service

68

MS

NPDB

DONOR NETWORK

ORIGINATING NETWORK RECEIPIENT NETWORK

MS

providers, which make it difficult to manage the terms of each agreement, and track the porting

requests. This approach is very complex, and the complexity is further increased with increasing

number of service providers.

Centralized approach

In this approach, the regulatory authority of the country sets up the guidelines, policies and

processes for number portability. All the service providers in the country have a shared and well-

defined interface with a centralized NP administration center for processing the porting request of

a number. This adheres to a clear set of service level agreements for each of the steps involved in

the process and it is mandatory for the service providers to follow them.Any porting request from

any of the service providers is sent to the NP administration center first, to which all the service

providers’ number portability solutions are integrated with. A request that comes from the new SP

to the NP administration center is sent to the present serving SP for clearance and once this is

done the central NP administration center broadcasts the porting information to all the service

providers in the country. As specified above, the porting request can be initiated by either of the

current serving SP or the new SP (recipient). This is decided by the regulatory body of the

country.

CHANGES IN OLD SCENARIOS OF ROUTING

As far as changes in hardware is concerned it is more or less negligible. Only NPDB server is

added and CDB is their to keep regulation in the system.

Technical aspect of routing before its implementation was their routing was purely based n levels

and now a 4 digit LRN is used to route every call.Process wise ACQ(all call query) will be there

so now every call has to go through NPDB server query

CONCLUSION :-

India is the 2nd largest telecom market in the world after China. And with ongoing technical

revolutions in this sector, number is set to outclass China. The wireless segment, with 392mn

subscribers, grew at rate of 62% over last 5 years. The target of 500mn subscribers by end of

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calendar 2010 seems to be quite achievable. Mobile number portability (MNP) has been enforced

in the majority of developed world markets by regulators as a means of increasing effective

competition in local mobile markets. It seems evident that MNP, if adopted in the right way and

under the right market conditions with true spirit, has the effect of furthering competition and

providing cheaper services for mobile customers. Number portability would provide an

opportunity to the consumers to change the Operator (s), while maintaining the same code and

same number, if service provider is unable to offer its customers variety of more competitive

services, with better quality and at affordable rates, definitely the targets of an Operator for

attracting a huge number of subscribers would remain unmet and consequent loss of a subscriber

base to it. Although MNP will be more a entangled & complicated process but its boon for

customers will surely outclass its complexity.

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BIBLIOGRAPHY

1. Course book on CDMA by H.Holma, A.Toskala, John Wiley & Sons.

2. Basics of Telecom.

3. www.tatatele.co.in

4. www.google.com

5. www.ss7.com

6. www.erricson.com

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