network resources notes

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Table of Contents Network Processors................................................... 1 Network Interface Card (NIC)........................................1 Modem...............................................................1 Hub.................................................................1 Switch..............................................................1 Router..............................................................1 Multiplexer.........................................................2 De-multiplexer......................................................2 Networks............................................................. 3 Internet............................................................3 Intranet............................................................3 Extranet............................................................3 Peer-to-Peer Network................................................4 Client Server Network...............................................4 Virtual Private Network (VPN).......................................5 Local Area Network (LAN)............................................5 Metropolitan Area Network (MAN).....................................5 Wide Area Network (WAN).............................................6 Wireless LAN........................................................7 Wireless WAN........................................................7

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Page 1: Network Resources Notes

Table of Contents

Network Processors.....................................................................................................................................1

Network Interface Card (NIC)..................................................................................................................1

Modem....................................................................................................................................................1

Hub..........................................................................................................................................................1

Switch......................................................................................................................................................1

Router......................................................................................................................................................1

Multiplexer..............................................................................................................................................2

De-multiplexer.........................................................................................................................................2

Networks.....................................................................................................................................................3

Internet....................................................................................................................................................3

Intranet....................................................................................................................................................3

Extranet...................................................................................................................................................3

Peer-to-Peer Network.............................................................................................................................4

Client Server Network.............................................................................................................................4

Virtual Private Network (VPN).................................................................................................................5

Local Area Network (LAN)........................................................................................................................5

Metropolitan Area Network (MAN).........................................................................................................5

Wide Area Network (WAN).....................................................................................................................6

Wireless LAN............................................................................................................................................7

Wireless WAN..........................................................................................................................................7

Network Topology.......................................................................................................................................8

Mesh Topology........................................................................................................................................9

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Advantages..........................................................................................................................................9

Disadvantages......................................................................................................................................9

Star Topology.........................................................................................................................................10

Advantages........................................................................................................................................10

Disadvantages....................................................................................................................................10

Ring Topology........................................................................................................................................12

Advantages........................................................................................................................................12

Disadvantages....................................................................................................................................12

Bus Topology.........................................................................................................................................13

Advantages........................................................................................................................................13

Disadvantages....................................................................................................................................13

Hybrid Topology....................................................................................................................................14

Advantages........................................................................................................................................14

Disadvantage.....................................................................................................................................14

Wired Media..............................................................................................................................................15

Twisted Pair...........................................................................................................................................15

Unshielded Twisted Pair (UTP)..........................................................................................................15

Shielded Twisted Pair (STP)...............................................................................................................15

Coaxial Cable.........................................................................................................................................16

Fiber Optic Cable / Optical Fiber Cable..................................................................................................16

Submarine Communications Cable........................................................................................................19

Wireless Media..........................................................................................................................................20

Microwave Transmission.......................................................................................................................20

Properties..........................................................................................................................................20

Uses...................................................................................................................................................20

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Satellite Communication.......................................................................................................................21

Geostationary Satellites.....................................................................................................................21

Cellular Networks..................................................................................................................................23

Network Software.....................................................................................................................................25

Network Operating Systems..................................................................................................................25

Network Management..........................................................................................................................25

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Network Processors

Network Interface Card (NIC)A network card, network adapter or NIC (network interface controller) is a piece of computer hardware designed to allow computers to communicate over a computer network. It is both an OSI layer 1 (physical layer) and layer 2 (data link layer) device. It allows users to connect to each other either by using cables or wirelessly. It is also incorrectly and commonly called LAN Card.

ModemA modem (modulator-demodulator) is a device that modulates an analog carrier signal to encode digital information, and also demodulates such a carrier signal to decode the transmitted information. The goal is to produce a signal that can be transmitted easily and decoded to reproduce the original digital data. Modems can be used over any means of transmitting analog signals, from light emitting diodes to radio.

HubA common connection point for devices in a network. Hubs are commonly used to connect computers in a LAN. A hub contains multiple ports. When a packet arrives at one port, it is sent to all the other ports so that all connected computers on the LAN receive all packets. In simpler words hubs always broadcast all data.

Switch A network switch is a computer networking device that connects network segments. Switches may operate at one or more layers of the OSI model, including data link, network, or transport (i.e., end-to-end). A switch contains multiple ports. Network switches are intelligent devices and when data packets arrive at it they send them only to the computer that they are meant for. Switches are capable of unicast, multicast and even broadcast.

RouterA router is a device that forwards data packets across computer networks. Routers perform the data "traffic directing" functions on the Internet. A router is a microprocessor-controlled device that is connected to two or more data lines from different networks. When a data packet comes in on one of the lines, the router reads the address information in the packet to determine its ultimate destination. Then, using information in its routing table, it directs the packet to the next network on its journey. A data packet is typically passed from router to router through the networks of the Internet until it gets to its destination computer. Routers also perform other tasks such as translating the data transmission protocol of the packet to the appropriate protocol of the next network, and preventing unauthorized access to a network by the use of a firewall.

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Multiplexer

Multiplexing (also known as muxing) is a method by which multiple analog message signals or digital data streams are combined into one signal over a shared medium. The aim is to share an expensive resource. For example, in telecommunications, several telephone calls may be carried using one wire. Multiplexing originated in telegraphy, and is now widely applied in communications. The device that performs the multiplexing is called a multiplexer (MUX). Frequently a multiplexer and demultiplexer are combined into a single device capable of processing both outgoing and incoming signals.

De-multiplexer

Multiplexing (also known as muxing) is a method by which multiple analog message signals or digital data streams are combined into one signal over a shared medium. The aim is to share an expensive resource. For example, in telecommunications, several telephone calls may be carried using one wire. The reverse process, known as demultiplexing, can extract the original channels on the receiver side. The device that performs the reverse process is called a demultiplexer (DEMUX). Frequently a multiplexer and demultiplexer are combined into a single device capable of processing both outgoing and incoming signals.

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Networks

InternetThe Internet is a global system of interconnected computer networks that use the standard Internet Protocol Suite (TCP/IP) to serve billions of users worldwide. It is a network of networks that consists of millions of private, public, academic, business, and government networks, of local to global scope, that are linked by a broad array of electronic, wireless and optical networking technologies. The Internet carries a vast range of information resources and services, such as the inter-linked hypertext documents of the World Wide Web (WWW) and the infrastructure to support electronic mail.

IntranetAn intranet is a private computer network that uses Internet Protocol technology to securely share any part of an organization's information or network operating system within that organization. The term is used in contrast to internet, a network between organizations, and instead refers to a network within an organization. Sometimes the term refers only to the organization's internal website, but may be a more extensive part of the organization's information technology infrastructure. It may host multiple private websites and constitute an important component and focal point of internal communication and collaboration.

ExtranetAn extranet is a computer network that allows controlled access from the outside, for specific business or educational purposes. An extranet can be viewed as an extension of a company's intranet that is extended to users outside the company, usually partners, vendors, and suppliers. It has also been described as a "state of mind" in which the Internet is perceived as a way to do business with a selected set of other companies (business-to-business, B2B), in isolation from all other Internet users. In contrast, business-to-consumer (B2C) models involve known servers of one or more companies, communicating with previously unknown consumer users. An extranet provides access to needed services for channel partners, without granting access to an organization's entire network.

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Peer-to-Peer Network

When several computers are interconnected, but no computer occupies a privileged position, the network is usually referred to as a peer-to-peer network. In this type of network, every computer can communicate with all the other machines on the network, but in general each one stores its own files and runs its own applications.

Client Server Network

With a client-server network, one or more servers will perform critical functions on behalf of the other machines (the clients) on the network. These functions might include user authentication, data storage, and the running of large, shared, resource-intensive applications such as databases and client relationship management (CRM) software. Typically, both peer-to-peer and client-server networks rely on a shared Internet connection for access to external resources of these basic network structures.

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Virtual Private Network (VPN)

A virtual private network (VPN) is a secure way of connecting to a private Local Area Network at a remote location, using the Internet or any insecure public network to transport the network data packets privately, using encryption. The VPN uses authentication to deny access to unauthorized users, and encryption to prevent unauthorized users from reading the private network packets. The VPN can be used to send any kind of network traffic securely, including voice, video or data.

VPNs are frequently used by remote workers or companies with remote offices to share private data and network resources. VPNs may also allow users to bypass regional internet restrictions such as firewalls, and web filtering, by "tunneling" the network connection to a different region.

Local Area Network (LAN)A local area network (LAN) is a computer network covering a local area, like a home, office, or group of buildings. The defining characteristics of LANs in contrast to WANs (wide area networks) are: their much higher data rates; smaller geographic range; and that they do not require leased telecommunication lines.

Metropolitan Area Network (MAN)Metropolitan Area Networks or MANs are large computer networks usually spanning a campus or a city. They typically use wireless infrastructure or optical fiber connections to link their sites.

For instance a university or college may have a MAN that joins together many of their local area networks (LANs) situated around site of a fraction of a square kilometer. Then from their MAN they could have several wide area network (WAN) links to other universities or the Internet. Specifically, this type of MAN is known as a campus area network.

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Wide Area Network (WAN)A wide area network or WAN is a computer network covering a broad geographical area. Contrast with metropolitan area networks (MANs) or local area networks (LANs) that are usually limited to a room, building or campus. The largest and most well-known example of a WAN is the Internet.

WANs are used to connect local area networks (LANs) together, so that users and computers in one location can communicate with users and computers in other locations. Many WANs are built for one particular organization and are private. Others, built by Internet service providers, provide connections from an organization's LAN to the Internet. WANs are most often built using leased lines. At each end of the leased line, a router connects to the LAN on one side and a hub within the WAN on the other. Leased lines can be very expensive. Instead of using leased lines, WANs can also be built using less costly circuit switching or packet switching methods.

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Wireless LAN

A wireless local area network (WLAN) links two or more devices using some wireless distribution method and usually providing a connection through an access point to the wider Internet. This gives users the mobility to move around within a local coverage area and still be connected to the network.

Wireless LANs have become popular in the home due to ease of installation, and the increasing to offer wireless access to their customers; often for free. Large wireless network projects are being put up in many major cities: New York City, for instance, has begun a pilot program to provide city workers in all five boroughs of the city with wireless Internet access. Wireless LAN is more commonly called Wi-Fi (Wireless Fidelity) which is not a technical term.

Wireless WANA wireless wide area network (WWAN), is a form of wireless network. A wide area network differs from a local area network by the technology used to transmit the signal and their size. Wireless networks of all sizes deliver data in the form of telephone calls, web pages, and streaming video.

A WWAN differs from WLAN (wireless local area network) in that it uses mobile telecommunication cellular network technologies such as WiMAX (Worldwide Interoperability for Microwave Access).

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Comparisons and confusion between WiMAX and Wi-Fi are frequent because both are related to wireless connectivity and Internet access

WiMAX is a long range system, covering many kilometers, allowing access to a network, in most cases the Internet while Wi-Fi is more popular in end user devices.

Although Wi-Fi and WiMAX are designed for different situations, they are complementary. WiMAX network operators typically provide a WiMAX Subscriber Unit which connects to the metropolitan WiMAX network and provides Wi-Fi within the home or business for local devices (e.g., Laptops, Wi-Fi Handsets, smartphones) for connectivity. This enables the user to place the WiMAX Subscriber Unit in the best reception area (such as a window), and still be able to use the WiMAX network from any place within their residence.

Network Topology

Network topology is the layout pattern of interconnections of the various elements (links, nodes, etc.) of a computer network. Topology can be considered as a virtual shape or structure of a network. This shape does not correspond to the actual physical design of the devices on the computer network. The computers on a home network can be arranged in a circle but it does not necessarily mean that it represents a ring topology.

Following are some of the most common network topologies

Mesh Topology

Star Topology

Ring Topology

Bus Topology

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Mesh Topology

A network topology where each of the computers and network devices are interconnected with one another, allowing for most transmissions to be distributed, even if one of the connections go down. This topology is not commonly used for most computer networks as it is difficult and expensive to have redundant connection to every computer. However, this topology is commonly used for wireless networks.

Advantages

The use of dedicated link guarantees that each connection can carry its own data load. It eliminates traffic problem.

If one link becomes unusable, it does not harm the entire system.

It is easy to troubleshoot.

Disadvantages

A full mesh network can be very expensive.

It is difficult to install and reconfigure.

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Star Topology

Star networks are one of the most common computer network topologies. In its simplest form, a star network consists of one central switch, hub or computer, which acts as a conduit to transmit messages. This consists of a central node, to which all other nodes are connected; this central node provides a common connection point for all nodes through a hub. Thus, the hub and leaf nodes, and the transmission lines between them, form a graph with the topology of a star.

The star topology reduces the chance of network failure by connecting all of the systems to a central node. All peripheral nodes may thus communicate with all others by transmitting to, and receiving from, the central node only. The failure of a transmission line linking any peripheral node to the central node will result in the isolation of that peripheral node from all others, but the rest of the systems will be unaffected. Data on a star network passes through the hub, switch, or concentrator before continuing to its destination. The hub, switch, or concentrator manages and controls all functions of the network. It is also acts as a repeater for the data flow. This configuration is common with twisted pair cable. However, it can also be used with coaxial cable or optical fiber cable.

Advantages

It is easy to maintain and modify network.

Adding or removing computers can be done without disturbing the network.

Finding faults becomes very simple.

Single computer failure does not bring down the whole network.

It is more flexible than other topologies.

Disadvantages

If central hub fails, the entire network breaks down.

It requires a large length of cable to connect computers.

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It is more expensive.

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Ring Topology

A ring network is a network topology in which each node connects to exactly two other nodes, forming a single continuous pathway for signals through each node - a ring. Data travels from node to node, with each node along the way handling every packet.

Because a ring topology provides only one pathway between any two nodes, ring networks may be disrupted by the failure of a single link. A node failure or cable break might isolate every node attached to the ring.

Every computer is connected to next computer in a ring. Each computer receives message from the previous computer and transmits it to the next computer. The message flows in one direction. The message is passed around the ring until it reaches the correct destination computer.

Advantages

It is less expensive than star topology.

Every computer has equal access to the network.

Disadvantages

Failure of one computer in the ring can affect the whole network.

It is difficult to troubleshoot.

Adding or removing computers affect the whole network.

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Bus Topology

A bus network topology is a network architecture in which a set of clients are connected via a shared communications line, called a bus.

Bus topology is the cheapest way of connecting computers to form a workgroup or departmental LAN, but it has the disadvantage that a single loose connection or cable break can bring down the entire LAN

Advantages

Bus is easy to use and understand and inexpensive simple network

It is easy to extend a network by adding cable with a repeater that boosts the signal and allows it to travel a longer distance.

Disadvantages

A bus topology becomes slow by heavy network traffic with a lot of computer because networks do not coordinate with each other to reserve times to transmit.

It is difficult to troubleshoot a bus because a cable break or loose connector will cause reflections and bring down the whole network.

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Hybrid TopologyA hybrid topology connects network components by combining the features of two or more other topologies (such as star, bus, ring and token-ring). The resulting hybrid topology exhibits features (and limitations) of its comprising network components. Examples of hybrid networks include the star bus network (that combines a star network topology and a bus network topology) and a star ring network, which combines the features of a star network topology and a ring network topology.

Advantages

It is reliable and the failure of one node (or connected system) does not affect the performance of the network. There are multiple pathways between the nodes.

A hybrid network combines different networks and is therefore able to provide features and exhibit characteristics of both.

It can be employed in a variety of environments and is typically used to wire a corporate network or a large LAN (local area network.)

Disadvantage

Expensive & Complex

It is typically more expensive than other topologies

It requires more cabling between its hardware devices than other types of network topologies.

It is difficult to set up and troubleshoot. Problems in connected nodes are often hard to pinpoint and isolate.

Addition of other nodes or devices to the network is cumbersome.

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Wired Media

Twisted PairTwisted pair cabling is a type of wiring in which two conductors (the forward and return conductors of a single circuit) are twisted together for the purposes of canceling out electromagnetic interference (EMI) from external sources; for instance, electromagnetic radiation and crosstalk between neighboring pairs. There are two basic types of twisted pair cables: Unshielded Twisted Pair and Shielded Twisted Pair.

Unshielded Twisted Pair (UTP)

Unshielded Twisted Pair, a popular type of cable that consists of two unshielded wires twisted around each other. Due to its low cost, UTP cabling is used extensively for local-area networks (LANs) and telephone connections. UTP cabling does not offer as high bandwidth or as good protection from interference as coaxial or fiber optic cables, but it is less expensive and easier to work with.

Shielded Twisted Pair (STP)

Shielded Twisted Pair is a type of copper telephone wiring in which each of the two copper wires that are twisted together are coated with an insulating coating that functions as a ground for the wires. The extra covering in shielded twisted pair wiring protects the transmission line from electromagnetic interference leaking into or out of the cable. STP cabling often is used in computer networks.

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Coaxial Cable

Coaxial cable is an electrical cable with an inner conductor surrounded by a flexible, tubular insulating layer, surrounded by a tubular conducting shield. The shield minimizes electrical and radio frequency interference. The term coaxial comes from the inner conductor and the outer shield sharing the same geometric axis.

Coaxial cabling is the primary type of cabling used by the cable television industry and is also widely used for computer networks. Although more expensive than standard telephone wire, it is much less susceptible to interference and can carry much more data.

Fiber Optic Cable / Optical Fiber Cable

An optical fiber is a flexible, transparent fiber made of very pure glass (silica) not much bigger than a human hair that acts as a waveguide, or "light pipe", to transmit light between the two ends of the fiber. Optical fibers are widely used in fiber-optic communications, which permits transmission over longer distances and at higher bandwidths (data rates) than other forms of communication. Fibers are used instead of metal wires because signals travel along them with less loss and are also immune to

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electromagnetic interference. Fibers are also used for illumination, and are wrapped in bundles so they can be used to carry images, thus allowing viewing in tight spaces.

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Optical fiber cable typically consists of a transparent core surrounded by a transparent cladding material with a lower index of refraction. Light is kept in the core by total internal reflection.

Fiber optics has several advantages over traditional metal communications lines:

Fiber optic cables have a much greater bandwidth than metal cables. This means that they can carry more data.

Fiber optic cables are less susceptible than metal cables to interference.

Fiber optic cables are much thinner and lighter than metal wires.

Data can be transmitted digitally (the natural form for computer data) rather than analogically.

The main disadvantage of fiber optics are

The cables are expensive to install.

They are more fragile than wire and are difficult to splice.

Fiber optics is a particularly popular technology for local-area networks. In addition, telephone companies are steadily replacing traditional telephone lines with fiber optic cables. In the future, almost all communications will employ fiber optics.

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Submarine Communications CableA submarine communications cable is a cable laid beneath the sea to carry telecommunications under stretches of water. As of 2010, submarine cables link all the world's continents except Antarctica.

The first submarine communications cables carried telegraphy traffic. Subsequent generations of cables carried first telephony traffic, then data communications traffic. All modern cables use optical fiber technology to carry digital payloads, which are then used to carry telephone traffic as well as Internet and private data traffic. They are typically 69 millimetres (2.7 in) in diameter and weigh around 10 kilograms per metre (7 lb/ft), although thinner and lighter cables are used for deep-water sections.

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Wireless Media

Microwave TransmissionMicrowave transmission refers to the technology of transmitting information or power by the use of radio waves whose wavelengths are conveniently measured in small numbers of centimeters; these are called microwaves. Microwaves are widely used for point-to-point communications because their small wavelength allows conveniently-sized antennas to direct them in narrow beams, which can be pointed directly at the receiving antenna. This allows nearby microwave equipment to use the same frequencies without interfering with each other, as lower frequency radio waves do. Another advantage is that the high frequency of microwaves gives the microwave band a very large information-carrying capacity.

Properties

Suitable over line-of-sight transmission links without obstacles

Provides large useful bandwidth when compared to lower frequencies (HF, VHF, UHF)

Affected by temperature, pressure and humidity of the atmosphere, rain, snow and hail, sand storms, clouds, mist and fog, strongly depending on the frequency.

Uses

One-way (eg. TV broadcasting) and two-way telecommunication using satellites

Terrestrial microwave radio relay links in broadcasting and telecommunications networks including eg. backbone or backhaul carriers in cellular networks linking BTS-BSC and BSC-MSC.

Wireless transmission of power

Proposed systems eg. for connecting solar power collecting satellites to terrestrial power grids

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Satellite Communication

A communications satellite (sometimes abbreviated to COMSAT) is an artificial satellite stationed in space for the purpose of telecommunications. Modern communications satellites use a variety of orbits including geostationary orbits.

For fixed (point-to-point) services, communications satellites provide a microwave radio relay technology complementary to that of submarine communication cables. They are also used for mobile applications such as communications to ships, vehicles, planes and hand-held terminals, and for TV and radio broadcasting, for which application of other technologies, such as cable, is impractical or impossible.

Geostationary Satellites

Geostationary satellites are located exactly above the earth’s equator and revolve around the earth in a circular orbit. It’s revolving speed and direction (west to east) is exactly same as that of the earth, which

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makes it look stationary from the earth’s surface. The exact altitude of these satellites above the equator is approximately 36,000 Kilometers (22369 Miles). The orbital path of a geostationary satellite is called the Clarke Belt, in honor of science fiction author Arthur C. Clarke.

A geostationary satellite can be contacted via a directional antenna, typically a little antenna dish, targeted at the location in the sky where the satellite seems to float. One geostationary satellite can cover approximately 40 percent of the earth’s surface area. Three such geostationary satellites, each separated by 120 degrees of longitude, can offer coverage of the complete earth surface area, with the omission of little circular areas situated at the north and south geographic poles. The typical service life expectancy of a geostationary satellite is ten to fifteen years. There are approximately 300 operational geosynchronous satellites. These satellites have revolutionized global communications, television broadcasting and weather forecasting, and have a number of important defense and intelligence applications.

They are extremely useful for the following

Meteorology: real time operational surveys of the troposphere, cloud systems, sea and land surface temperatures; data acquisition and dissemination.

Telecommunications: worldwide operational telecommunication systems for telephones, TV and digitized transmission lines.

Army: alarm systems - detection of missile launches.

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Cellular Networks

A cellular network is a radio network distributed over land areas called cells, each served by at least one fixed-location transceiver known as a cell site or base station. When joined together these cells provide radio coverage over a wide geographic area. This enables a large number of portable transceivers (e.g., mobile phones, pagers, etc.) to communicate with each other and with fixed transceivers and telephones anywhere in the network, via base stations, even if some of the transceivers are moving through more than one cell during transmission.

Cellular networks offer a number of advantages over alternative solutions:

increased capacity

reduced power use

larger coverage area

reduced interference from other signals

In a cellular radio system, a land area to be supplied with radio service is divided into regular shaped cells, which can be hexagonal, square, circular or some other irregular shapes, although hexagonal cells are conventional. Each of these cells is assigned multiple frequencies (f1 - f6) which have corresponding radio base stations.

The increased capacity in a cellular network, compared with a network with a single transmitter, comes from the fact that the same radio frequency can be reused in a different area for a completely different transmission.

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The most common example of a cellular network is a mobile phone (cell phone) network. A mobile phone is a portable telephone which receives or makes calls through a cell site (base station), or transmitting tower. Radio waves are used to transfer signals to and from the cell phone.

Modern mobile phone networks use cells because radio frequencies are a limited, shared resource. Cell-sites and handsets change frequency under computer control and use low power transmitters so that a limited number of radio frequencies can be simultaneously used by many callers with less interference.

A cellular network is used by the mobile phone operator to achieve both coverage and capacity for their subscribers. Large geographic areas are split into smaller cells to avoid line-of-sight signal loss and to support a large number of active phones in that area. All of the cell sites are connected to telephone exchanges (or switches), which in turn connect to the public telephone network.

In cities, each cell site may have a range of up to approximately ½ mile, while in rural areas, the range could be as much as 5 miles. It is possible that in clear open areas, a user may receive signals from a cell site 25 miles away.

Since almost all mobile phones use cellular technology, including GSM, CDMA, and AMPS (analog), the term "cell phone" is in some regions, notably the US, used interchangeably with "mobile phone". However, satellite phones are mobile phones that do not communicate directly with a ground-based cellular tower, but may do so indirectly by way of a satellite.

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Network Software

Network Operating SystemsA networking operating system (NOS) is the software that runs on a server and enables the server to manage data, users, groups, security, applications, and other networking functions. The network operating system is designed to allow shared file and printer access among multiple computers in a network, typically a local area network (LAN), private network or to other networks. The most popular network operating systems are Microsoft Windows Server 2003, Microsoft Windows Server 2008, UNIX, Linux, Mac OS X, and Novell NetWare.

Network Operating Systems are based on a client/server architecture in which a server enables multiple clients to share resources. The Network Operating System can also do the following:

Centrally manage network resources, such as programs, data and devices.

Secure access to a network.

Allow remote users to connect to a network.

Allow users to connect to other networks like the Internet.

Back up data and make sure it's always available.

Allow for simple additions of clients and resources.

Monitor the status and functionality of network elements.

Distribute programs and software updates to clients.

Ensure efficient use if a server's capabilities.

Network ManagementNetwork management refers to the activities, methods, procedures, and tools that pertain to the operation, administration, maintenance, and provisioning of networked systems.

Operation deals with keeping the network (and the services that the network provides) up and running smoothly. It includes monitoring the network to spot problems as soon as possible, ideally before users are affected.

Administration deals with keeping track of resources in the network and how they are assigned. It includes all the "housekeeping" that is necessary to keep the network under control.

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Maintenance is concerned with performing repairs and upgrades—for example, when equipment must be replaced, when a router needs a patch for an operating system image, when a new switch is added to a network. Maintenance also involves corrective and preventive measures to make the managed network run "better", such as adjusting device configuration parameters.

Provisioning is concerned with configuring resources in the network to support a given service. For example, this might include setting up the network so that a new customer can receive voice service.

A common way of characterizing network management functions is FCAPS—Fault, Configuration, Accounting, Performance and Security.

Functions that are performed as part of network management accordingly include controlling, planning, allocating, deploying, coordinating, and monitoring the resources of a network, network planning, frequency allocation, predetermined traffic routing to support load balancing, cryptographic key distribution authorization, configuration management, fault management, security management, performance management, bandwidth management, Route analytics and accounting management.

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