PROJECT REPORT ON

NETWORKING AND COMMUNICATION SYSTEM

HELD IN

ONGC ASSAM ASSET, NAZIRA & SIVASAGAR

SUBMITTED FOR THE

INDUSTRIAL TRAINING PROGRAMME

UNDERTAKEN AT

INFOCOM SERVICES,

OIL AND NATURAL GAS CORPORATION LTD

ASSAM ASSET, SIVASAGAR & NAZIRA

SUBMITTED BY :

ABHISHEK NARAYAN

B.TECH. ( ECE 4th semester )

JAYPEE INSTITUTE OF

INFORMATION TECHINOLOGY

ACKNOWLEDGEMENT

Many people have helped me in bringing out my training. I extended my

gratitude to them all for helping me in their own individual ways in completing

the training program.

I would like to express my gratitude to the management of RTI ONGC,

Sivasagar, Shri D. P. Singh, GM (E&T), Head Infocom, Nazira, Mrs. Jharna Dutta

Bora, Sr HR Executive, RTI, Sivasagar for providing me the opportunity to undergo

training at Assam Asset, ONGC.

I would like to thank Mr. Amal Krishna, C.E. (E&T), Mr. B.S. Bhatia, C.E.

(E&T) for providing me the opportunity to complete my training at Infocom

Services Nazira, a department of Oil and Natural Gas Corporation Ltd. Assam

Asset. Their valuable guidance and encouraging support along with their friendly

approach has helped me tremendously during my training. I am immensely

grateful to them.

I would also like to thank all the engineers from CMC LTD, BPL LTD & E.S LTD

who helped me in completing my project.

I deliver a special note of thanks to all the employees of ONGC, Assam Asset

for their unforgettable cooperation.

NO OBJECTION CERTIFICATE

This is to certify that Mr. Abhishek Narayan has undergone his summer training at Infocom Services, Assam Asset, ONGC, Nazira. To the best of my knowledge the report does not contain anything that can endanger the secrecy and working of the organization.

Mentor

CERTIFICATE

This is to certify that Mr. Abhsishek Narayan, 4th semester, B.TECH. in ECE has

undergoing regular visit to Infocom Service O.N.G.C Ltd Assam Asset, Sivasagar

and Nazira and hence completed his industrial training of 30 days (from 16th June

to 15th July ) with our full satisfaction, he has prepared the study report on

operation & process in Infocom and support team, O.N.G.C.

This is to certify that Shri Sambit Jyoti Sarmah, student of 6 th semester, Btech

(Electronics & Communication) Engineering student of Don Bosco College of

Engineering and Technology, Azara, Guwahati, has undergone summer industrial

training at Infocom Services, ONGC, Nazira from 15th June 2012 to 16th July 2012.

He has taken keen interest in all the activities and had followed the training

programs sincerely.

Mentor

LINE COMMUNICATION

VOICE CONNECTIVITY

ONGC’s private exchange works on Voice over Internet Protocol (VoIP). It’s optimized for transmission of voice over internet and packet-transfer networks.

Voice Signal Transmit

Voice Signal Receive

Current Detector

Current Detector

Telephone Exchange Carrier System

EPABX based Telephone Exchange (E&M system) being operated in ONGC

EPABX

It’s an equipment that’s made working in offices much simpler by fully servicing the internal and external needs, allowing for various other features to be added to the service.

EPABX is a telephone exchange operated within an organization, used for switching calls between internal lines and the Public Service Telephone Network (PSTN) lines.

EPABX technology is divided into roughly 4 parts

T

R

T1

R1

E lead

SG lead

SB lead

M lead

-48v

-48v

If the user inputs for

outside calls, he’s connected to the outside

line (paid service),

otherwise he’s connected to the internal network to contact an

internal user (free service), else an error

tone is sent to the user

A trunk interface

A station interface

A switching fabric

A call control database

It waits till someone picks up the phone

The dial tone is sent to the user

The user inputs a number

The call

ends

Call ended tone is sent to the user

The user is then

required to put the

phone down

The call is then ended by terminating the control switch fabric.

OPERATING PRINCIPLE OF EPABX

11

INTERNAL WORKINGS OF THE ONGC ASSAM ASSET VoIP SYSTEM

In a normal scenario

Nazira, Sivasagar, Lakwa, Galeki work as a single system

Active server at Nazira takes handles the entire network while the others are in sleep mode.

In case of a breakdown of the servers

Duplicated ESS (Enterprise Survival Server) placed at Sivasagar becomes live in-case of failure of

Both IP links

Both servers at Nazira

Local Survivable Server at Lakwa and Galeki becomes live and serves the internal requirements of the colonies in case of failure of IP links connecting them to Nazira.

Nazira

(mainframe)

Sivasagar

Lakhwa

Galeki

Main Gateway G650 systemBackup Gateway G650 system

Main Gateway G650 systemBackup Gateway G650 system

ICNET

PSTN

(external network)

Satellite Communication

External ONGC Networks

External Calls

Main Gateway G650 system

Main Gateway G650 system

NOTE: here every intercom connection gets routed through the servers at Nazira

FAILOVER SCENARIOS

Primary server failure at Nazira

Secondary server at Nazira becomes active

The entire communication network remains up and running using the secondary server of Nazira, without any disconnection of any ongoing call (Hot-Standby)

Duplicate ESS servers at Galeki and Lakwa in sleep mode

Failure of both servers at Nazira

Both ESS servers at Sivasagar become live, one becomes active and the other stays in stand-by mode

LSP servers at Galeki and Lakwa remain inactive

Failure of both servers at Nazira and one server at Sivasagar

Another backup ESS server becomes active

LSP servers at Galeki and Lakwa remain inactive

Failure of one IP link between Nazira and a location

CO/ Trunk lines

External to Internal Lines

Radio Link

OFC Lines

Satellite Uplink/Downlink

ENM Trunk

Intercom Connection to NaZira

Key: Telecom Line Linkages as a part of ONGC Assam Asset

The second IP link becomes active

The entire communication network between Nazira and that location remains up and running using the second link without disconnecting any ongoing calls

Duplicate ESS servers at Galeki and Lakwa remain inactive

Failure of both IP links between Nazira and another location

The location become totally isolated from the entire network

ESS/LSP of that location becomes active and handles the internal network requirements

Users of the location can communicate with the outside network using PSTN

EXCHANGE ROOM

SCADA: SUPERVISIORY CONROL AND DATA ACQUISITION

COMMMON SYSTEM COMPONENTS

One or more field data interface devices (RTU’s and PLC’s) that interface to field sensing devices and local control switch boxes and valve actuators.

A communication network system to transfer data between field data interfaces and control units and SCADA central host.

Central host computer servers (SCADA centre or Master Terminal)

Human Machine Interface (HMI) for

Providing SCADA central host and operator terminal application

Supporting communication lines

Monitoring and controlling field data interface devices remotely

FIELD DATA INTERFACE DEVICES

Equipments such as

Electric valve actuators

Electronic chemical dosing facilities

Motor control switch boards

form “hands” of a SCADA system that’ll allow it to automate the process its handling.

Remote Telemetry Units (RTU) convert electric signals received from field interface devices into language (communication protocol) that’s used to transmit data over communication channels.

They cannot handle sequential tasks, as they’re multi-task devices and cannot finish a task without interrupting it first.

Programmable Logic Controllers (PLC) contains information that can automate the working of system by bypassing SCADA centers, as there's a limited bandwidth available.

PLC’s were mainly used as a replacement for relay logic systems, which were traditionally used in RTU’s.

PLC does also have the capacity to transfer the state of operational systems to a remote computer.

They’re sequential circuits and cannot process serial tasks.

COMMUNICATION NETWORK

It’s intended to provide the means by which data can be transferred between the central host computer servers and the field-based RTUs via cables, telephone lines and radio.

CENTRAL HOST COMPUTER

It’s a computer or a network of computer servers that provide a man-machine operator interface to the SCADA system. The computers process the information received from, and sent to the RTU sites and present it to human operators in a form that the operators can work with.

OPERATOR WORKSTATIONS AND COMMUNICATION NETWORKS

Software products typically used within a SCADA system are as follows:

Central host computer operating system: Software used to control the central hostcomputer hardware. Operator terminal operating system: Software used to control the central hostcomputer hardware and contributes to the networking of the central host and the operator terminals.

Central host computer application: Software that handles the transmittal and receptionof data to and from the RTUs and the central host. The software also provides thegraphical user interface that offers site mimic screens, alarm pages, trend pages,and control functions.

Operator terminal application: Application that enables users to access informationavailable on the central host computer application.

Communications protocol drivers: Software that is usually based within the centralhost and the RTUs, and is required to control the translation and interpretation of thedata between ends of the communications links in the system

Communications network management software: Software required to control thecommunications network and to allow the communications networks themselves to bemonitored for performance and failures.

RTU automation software: Software that allows engineering staff to configure andmaintain the application housed within the RTUs (or PLCs).

SCADA PROTOCOLS

An RTU accepts commands to be able to:

Control output levels

Set analogue output levels

Respond to requests

Provides data to central SCADA mainframe

Every bit of data is correlated to SCADA mainframe in terms of unique addressing of the variables being recorded that imply certain conditions and factors prevalent in the on-site operating system.

Every protocol comprises of two message sets:

Master protocol, comprising of valid statements for master station’s response initiation.

RTU’s protocol, comprising of valid statements for on-site response to various conditions identified by interpreting data obtained via on-field interface devices and limitations set by the automation software.

EVOLUTION OF SCADA IN ONGC

ONGC implemented SCADA in1979 for five high platform remote locations in Mumbai high offshore. As technology advanced, the PDP 8-but single user system and non-intelligent RTU’ without remote control changed to a state of art fully intelligent system. This network now comprises of 11 master stations, 11 process platforms and around 135 well platforms.

ONGC’s SCADA parameters comprise of ~500 factors some of which are:

Flowing status for a high producing well flow line

Pressure of HP group header

Pressure of PP group header

Temperature at inlet and outlet of bath header

TIME DIVISION MULTIPLE ACCESSMultiple access is and extended form of multiplexing that is used in satellite communication systems as it offers connectivity in highly dispersed and remote locations and user requirements are able to vary the dynamic channel allocation.

MULTIPLE ACCESS PROTOCOLS

Various methods like FDMA, TDMA, SDMA, CDMA are employed to ensure minimum interference error between users in a multiple access system. (key to diagrams : x-time, y-frequency)

SDMA: allows for bandwidth allocation by exploiting spatial distribution of users requiring use of multi-beam antennas to separate out radio signals by pointing at different directions at different times.

Dynamic Resolution takes advantage of tracking system changes and allocates bandwidth to users based on:

Time of arrival

Probabilistic selection if user being allowed to transfer data from a dynamic distribution

Static resolution allows for data transmission by users. Its dependent upon:

User ID

Selection of user for bandwidth allocation from a random distribution

INSTALLED SYSTEM PARAMETERS OF ONGC TDMA SYSTEM

Multi Access System Demand Pre-Assignment

Number of Access Channels 60

Maximum subscriber capacity 1024

Service Ordinary telephone, FAX, Data communication with MODEM andcoin telephone(excluded base station)

Number of subscriber lines in a subscriber radio station

Upto 30 lines in a cabinet andupto 10 lines in an outdoor cabinet

Maximum Range Upto 500 km.

Delay time Adjustment Automatically adjusted

Coding/Decoding for VHF PCM (64 kbps)

Type of Emission Downlink CW

Modulation for RF QPSKBit Rate of 4Mbps via 2 linesRF Bandwidth of 2.4GHz

RF band 1.445-1.4935GHz

Frequency Separation 48.5Hz

TDMA CDMAFDMA

Power Supply Base: -48 DCRepeater and Remote: 24/-48 DCwith a +15/-10% error approximation

Operation Controller Network Management Services

Operating System WINDOWS 2000

Power Supply Float Cum Boast Charger charged by 12 batteries of 2 volts each

The field communication in Assam Asset of ONGC comprises of TDAM, MFTDMA, WLL.

The base station has a capacity to connect 1024 telephone users in the system using low-loss cables.

Network Management Services allows for:

Establishing new connections

Trouble-shooting telephone lines

Maintenance functions

Programming port number, channel number and card number to the new connections

Physical Components of the Radio TDMA system:

Omni directional Antenna: receives and transmits the RF signals

Duplexer: determines the nature of the signal to be transmitted and the received signal for its encoding and decoding purposes

Block diagram of the transmission and receiving of signal through the Duplexer

1 2 3 4 5 6

30 channel controller card

Voice channel cards

Data channel card

5 port channel per card connecting 5 users to voice access system

5 port channel per card out of which only half are utilized due to low

bandwidth requirement

Block diagram of Data Transmission

Block diagram of Voice Transmission

Data Card USERRouter

Programmed to send data as per its IP address

1 2 3 4 5 66

2-5

1 2 3 4 5 6

TDMA Room

MUX USER

Programmed to assign users a link to the 4-channel voice cards

Telephone Exchange

Router

SATELLITE COMMUNICATIONS

INTRODUCTION

In a geo-stationary satellite system, a message signal is transmitted via an uplink to a satellite, amplified in a transponder circuit on board the satellite that’s transmitted to earth stations.

Frequency bands that’re in frequent use:

In Sat-Comm., uplink frequency is greater than the downlink frequency because:

Higher frequency uplink implies low attenuation due to rainfall.

Signal is required to penetrate through the atmosphere to reach the satellite. This process involves for high power generation which is not possible on satellite.

The downlink frequency is lower cause of the low power generated in a satellite and also due to the small size of antennas in homes that require a direct link to the satellite.

Satellite’s main purpose is to communicate information and the type of information being transmitted determines the satellites design and orbit.

Communication satellites are primarily used in space as repeaters.

An earth station transmits Radio Frequency carriers to the satellite that the satellite receives and transmits it back to an earth station onto a specific footprint where the signal is received and demodulated.

Bus: it’s the platform that supports the payload from launch through the end of its life.

The bus’ control subsystem includes

Thermal control

Orbital control

Altitude control

Power system

Tracking, telemetry and command system

Payload:

It’s the specialized equipment required to perform its designed fuction. And includes

Antenna: Each payload has a specific operating frequency determined by its on-board components. Satellites use the same antenna to receive and transmit RF signals. This is made possible by the polarization of these signals being of opposite nature to prevent any distortion.

Wide Base Receivers: receives the full 500MHz RF uplink signal of the assigned band and the polarization. It uses a Local Oscillator to convert a signal to a downlink frequency and send it to the input Multiplexer.

Input Multiplexers: takes 500MHz set of frequencies and separates them into individual transponders that send the signals through a programmable attenuation device on its way to its assigned amplifier.

Programmable Attenuation Devices: adjusts the power of the prior to sending it to the amplifier.

Amplifiers: increases the power of the signals sent to the satellite and routes it to and output multiplexer

Output Multiplexers: recombines all transponders into a single 500 MHz wide-band configuration which is then routed through a wave guide to the antenna’s feed horn.

Basic components of a transponder on-board a satellite

Uplink Signal Downlink Signal

Transponder is a “transmitter responder”

It describes a single RF channel created by the input multiplexer and separates it into frequency channels.

Travelling Wave Tube Amplifier:

It mainly provides a high gain over a wide frequency range.

Uplink signal is usually converted to an intermediate frequency and is then converted to the desired downlink frequency

EM signal travels along e-beam travels at there is an energy TWT in a helix pathway the same speed approx. transfer from the e-beam to the signal

Propagation delay of a satellite channel becomes evident over long distances (570ms)

Local Oscillator

With vice signals, this propagation delay allows for and echo of the users voice to be heard at the receiver’s end which is reduced by and echo canceller

Echo Canceller subtracts an estimate of the echo from the signal on its return path

This is done by a filter that adapts itself by changing the channel characteristics.

Function Block Diagram of Pass-band Transmission Model

Message Signal

Carrier Wave

Assumptions made about the transmitted signal:

There exists a message source that emits one symbol every T seconds

The symbols belong to elements of M symbols denoted by m1, m 2, m 3,…… m n

Priori Probability elements P (m1), P(m 2) , P(m 3),…… P(m n) specify the output message

This message output is sent to the to the signal transmission encoder producing vector Si made up of N real elements for each M symbol.

Dimensions of N are always equal or less than that of M

Modulator then combines Si with carrier wave to produce Si(t) of duration T

Si(t) is the representation of symbol m generated by the message source

E i = for all i = 1,2,….M

Si(t) is then transmitted every T seconds

xX(t)Si(t) Simi

transmitter Receiver

Priori Probability is used in distinguishing the ways in which values for probabilities can be obtained. Its selected as per

Deductive reasoning

Principle of indifference

Assumptions made for the transmitting channel

Linear

Band-width is wide enough for signal transmission channel

There is low noise distortion

Footprint:

The satellite antennas are designed to cover a specific region of earth at a time to allow for

Concentration of power radiated from the satellite to the desired regions.

Increases the sensitivity of its receiving antenna minimizing interface with other adjacent satellite signals

The part of the earth covered by the satellite is the satellite’s footprint.

Orbit:

There are various levels of altitude that determines the functioning and maneuverability of satellites:

Synchronous Orbit: satellite moves at same speed as that of Earth and remains fixed over spot on Earth

Asynchronous Orbit: satellite doesn’t move at the same speed as that of the earth.

Polar Orbit: satellite remains fixed along its path on the latitudes and passes over polar caps.

The satellite is put into its desired orbital level by:

ground tracking

command functions

satellites altitude control

telemetry

orbital control systems

Once the satellite is in orbit, its maintained at the level throughout its lifetime by making periodic adjustments to maintain its ‘centre of box’.

Satellites have a limited fuel supply and have to be sent off into the super-sync orbit as space junk after exhausting all its fuel supply.

RADIO LINK ANALYSIS

Link analysis totals all the gains and losses incurred in operating a communication link. A communication link is dependent upon the line of sight for their operations and requires repeater stations in the path if is interrupted.

Additive White Gaussian Noise (AWGN) affects the working of any digital communication system

AWGN is a channel model whose Probability OF Errorcommunication is impaired by white noise with a constant spectral density and a Gaussian distribution of amplitude and can be caused by various factors such as:

Thermal vibration

Shot noise

Black body radiation

Properties of AWGN

Additive

Has a flat power spectral density

Have a Gaussian distribution Link Margins

(Eb/No)required

Waterfall curve of Probability Error to (Eb/No) ratio due to AWGN

(Eb/No)received = M * (Eb/No)required =» this is done to ensure a margin of link error providing protection against change and the unexpected distortions

(Eb/No)received

Free Space Propagation Model

In radio communication system, propagation of modulated signal is made [possible by transmitting antenna

Functions of transmitting antenna

Convert electric modulated signal into EM wave

Antenna acts as an impedence transforming transducer

The transducer matches impedence of antenna to that of the free space

To radiate energy in desired directions

Functions of receiving antenna

To convert EM field into an Electric Signal

Suppress radiation from unwanted directions

The transmitting antenna is viewed as point source due to spatial distance that separates it from the receiver

A complete description for field characteristics of far field characteristics of point source’ll involve EM field as function of space and time.

Gain

Directive gain = G(Ѳ,Ø) = Ф(Ѳ,Ø) P/4Л

Gmax = D = Ф(Ѳ,Ø)optimized

P/4Л

Power gain = ήradiation * D

ήradiation = Radiation Efficiency of the antenna

All these formulae are valid for transmission of data and if the transmission media is linear, passive and isotropic, then these variables are valid for the receiving antenna as per the RECIPROCITY PRINCIPLE

The power density at a receiver needs to be concentrated to a smaller region as compared to the 4 Л radians

Antenna bandwidth is planar measure of its solid angle of view

Beam-width is the angle subtended on two points on the main lobe of the field power pattern at which the peak-field power is reduced by 3dBs.\

Power gain of antenna ά (Antenna Bandwidth)-1

Sidelobes of the physical antenna are able to absorb unwanted radiation.

Effective Aperture

Effective aperture = power available at the antenna terminals Power/area of approx. polarized incident EM wave

A = λ2G ; λ = c/f= wavelength of the carrier wave 4Л

For reflector antennas; effective aperture ά ήaperture ά total efficiency physical aperture

Frii Free Space Equation

Propagation Equation of the radio communication link will be Pr = Pt * Gt * Gr * λ2G 4Л

Path loss: is the signal attenuation across the entire communication link OR difference between the transmitted power signal and the received power signal

Block Diagram for Earth Terminal Receiver

Low Noise Amplifier

Frequency Down Converter

Intermediate Frequency Amplifier

Local Oscillator

Receiver Antenna Transmitting Antenna

Power radiated:

Poynting Vector = rate of energy flow (W/m2) Area

Power Density = Poynting Vector

Power density only has a radial component as per assumptions

Power density = ρ(d) = Pt

4Лd2

Radiation intensity = Ф = d2 * ρ(d)

Power radiated inside an infinitesimally small solid angle dΩ is given by Ф(Ѳ,Ø) such that dΩ = sin Ѳ. d Ѳ. d Ø steradians

Power radiated = P = Ф(Ѳ,Ø).dΩ watts

Average power radiated = P watts 4Л

INFORMATION TECHNOLOGY

OSI SPECIFICATIONS

OSI specifications allow for data transfer between disparate hosts. Its not a physical model but rather a set of guidelines that application developers can use to create and implement applications on a network by providing a framework for creating and implementing networking standards, devices, and internetworking schemes.

OSI LAYERS

Application

Presentation

Session

Transport

Network

Data

Physical

Determines how applications within the

end stations communicate with each

Determines how data is transmitted from one to

another end

Provides the user an interface

Presents data and handles processes such as encryption

Keeps different application’s data separate

Provides data delivery and performs error correction before retransmission

Provides logical addressing which routers use for path determination

combines packets into bytes and bytes into frames, provides access to media using MAC address,

performs error detection not correction

The following network devices operate on all seven layers of OSI:

Network Management Stations,Web and application servers,Gateways,Network hosts,

Application layer:

Is the spot where user’s communicate with the system and becomes active when the system is about to be connected to the network

It’s responsible for identifying and establishing the availability of the intended communication partner and determines whether sufficient resources fo the intended communication exist.

The application layer acts as an interface between the actual application programs.

Presentation Layer:

It presents data to the application layer and is responsible for data translation and code formatting.

It’s a translator that provides coding and conversation functions

A successful data-transfer technique is to adapt the data into a standard format before transmission.

Computers are configured to receive this information and convert it into its native format for actual reading by the system.

The OSI defines how the data should be formatted.

Session Layer:

Its responsible for setting up, managing and tearing down sessions between Presentation layer entities.

It provides dialog control between devices

It coordinates communication by offering three different modes

Simple

Half duplex

Full duplex

It basically separates application’s data

Transport Layer:

It segments and reassembles data into data steam

Services located in the transport layer segment and reassemble data from upper-layer applications, and unite it into the same data stream.

They provide an end-to-end data transport service and establish logical connections between the sending host and destination host on an internetwork.

It provides a mechanism for multiplexing upper-layer applications, establishing sessions, and tearing down virtual circuits.

It hides details of any network-dependent information from higher layers by providing transparent data transfer.

Network Layer:

It manages device addressing, tracking location of devices on the network, and determines the best way to move data.

It may have to transport traffic between devices that aren’t locally attached.

It checks the IP address of the packet received on the router interface and looks up the destination network address in the routing table to select an exit route.

If the router cannot find an entry for the packet’s destination network in the routing table, the router drops the packet.

Physical Layer:

It sends and receives bits.

DATA ENCAPSULATION

SERVER ROOM

Servers PurposeAdditive Directory Server (ADC) server

ADC is a text protocol for a client-server network to create a simple protocol that doesn't require much effort in neither hub nor client, and is yet extensible.

DATA INFORMATION ON ADC LEVEL• Event• Timestamp• Buffer number• Location• Channel – property• Data type• Data status• Conversion information (polypara)• Value

TASKS• Collecting data from ADC modules• Managing ADC modules• Provide functionality for different ADC subsevers• Converting data into physical units• Storing data into the DOOCS archive• Responding to the DOOCS request• Sending data to the collector (multicast) with data conversion

Its basic task is to replicate directory information between Exchange 5.5 directory and the Active Directory and relies on the administrator to define connection agreements. These agreements name the servers involved in the replication cycle which directly replicates the objects into data

Dynamic Host It enables a server to automatically assign an IP address to a computer from a

Configuration Protocol (DHCP) server

defined range of numbers configured for a network.WORKING

The user with a DHCP client sends a broadcast request (DISCOVER/DHCPDISCOVER) looking or the DHCP server to answer which is redirected by the router to the server.

The server receives a DISCOVER packet and sends a reserved address to the client as a DHCPOFFER packet.

The server also configures the clients DNS servers, WINS servers, NTP servers, etc.

The client then sends a REQUEST packet letting the server know that it intends to use the address to which the server replies with a DHCPACK packet confirming a lease on the server for the user for a specified period of time.

Firewall A firewall is a protective service that protects the computer system from the network and internet. It prevents unauthorized use and access to the internal network by analyzing the data entering and exiting the network based upon the configuration.Hardware firewall is used in Nazira as they’re effective with little or no configuration and they can protect every machine on the network. A hardware firewall can uses packet filtering to examine the header of a packet to determine its source and location and to determine if the packet can be forwarded or needs to be dropped.

Windows Server Update Services (WSUS) server

It’s a program developed by Microsoft CO. enabling admins to manage the distribution of updates and hotfixes released for the Windows OS. Instead of each workstation to manually connect to Microsoft Update, testing the updates and then deploying updates using traditional methods, admins can use WSUS to download and updates to a central internal server that can dispatch the updates to all the systems connected to the server, allowing admins of full control over the types of updates available to users on the network.

Proxy Server

A proxy server is a server that acts as an intermediary for requests from clients seeking resources from other servers. The proxy server evaluates the request as a way to simplify and control their complexity.USES OF PROXY SERVERS

• To keep machines behind it anonymous for security• To speed up the access to resources• To apply company access policies to network services• To provide company internet usage report

• To scan transmitted content for malware before delivery• To scan outbound content for data loss prevention.

InterScan Web Security Suite (IWSS) server

VARIOUS PROBLEMS DUE TO AND INCREASED WEB BROWSING• Phishing• Viruses, worms, Trojans, spywares• Loss of productivity• Excessive bandwidth usage• Legal liability

To implement a url filtering at the web proxy and scan for malicious code content at the client is done at a single point at the application gateway in ONGC by the Trend Micro’s InterScan Web Security Suite v2.0 or the IWSS.IWSS is available for Solaris, Windows and Linux. The one at ONGC employs the Linux due t its enhanced security offerings.There are two processes for filtering traffic available

• Internet Content Adaptation Protocol (ICAP) allows for seamless coupling of caching and virus protection.

• Standard HTTP proxy can configure IWSS in standalone/chained proxy configuration.

IWSS offers two approaches for malware scanning:• Traditional content scanning via scan engines and pattern files• URL blocking via PhishTrap that lists websites regularly updated by

Trend-Micro known to host malware and phishing attempts.Websense Server It prevents networks from spyware, prevent users from viewing inappropriate

websites, discourage employees from browsing aimlessly, filtering urls and tracking internet usage via 2 servers installed in Nazira.

Active Directory (AD) Server

Active Directory provides a central location for network administration and security. It authenticates and authorizes all users and computers in a Windows domain type network assigning and enforcing security policies for all computers and installing or updating software by asking for User ID’s and passwords when users log in.

NNM Server It allows the network admin to view any problems in the working of the systems of the users logged into the network. When a device fails, the NNM servers analyze events associated with the failed systems and show their relative locations and status. It can also provide some predictive information that allows to identify potential failures in the system before they can occur.