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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.