Computer network & topology

PRESTIGE INSTITIUTE OF MANAGEMENT, GWALIOR

Network topologies, Server, work station,

Network Interface cards, Hub ,Switches ,cables .

S R TRIPATHI (mba)

Network Topology

Network topology is the pattern of interconnection between computer in a network. Network topology shows the physical layout of a network and shows links between them.

Types of Network Topology

1.Bus Topology:Also called linear bus topology. One wire connects all devices. Use in small organization. Advantages:1. Easy to set up2. Small amount of wire Disadvantages:3. Slow4. Easy to crash

Star TopologyAll computers connected to a hub.Host computer controls all network.

Advantages: One cable not crashes all the network. Easy to set up.

Disadvantages: One hub crashes all network. Uses a lot of cables.

Ring Topology

Each node connects to exactly two nodes forming a single continuous pathway for signals through each node.

Advantages: More reliable. Time to send data is known.Disadvantages: Difficult to trouble shoot. Slow.

Mesh topology

Each node relays data for the network. All mesh nodes cooperate in the distribution of data in the network.

Advantages: Easy to trouble shoot . Data will always delivered.Disadvantages: Lots of cable. Hard to setup.

Tree TopologyCombines characteristics of linear bus and star topologies. It consists of groups of star-configured workstations connected to a linear bus backbone cable.

Advantages: Easy to add new devices. Easy to remove any branch.

Disadvantages: More cable. One branch fail may fail all network.

Servera server is an instance of a computer program that accepts and responds to requests made by another program, known as a client. Less formally, any device that runs server software could be considered a server as well.Servers are used to manage network resources. For example, a user may setup a server to control access to a network, send/receive e-mail, manage print jobs, or host a website.

Work station

A workstation is a computer intended for individual use that is faster and more capable than a personal computer. It's intended for business or professional use (rather than home or recreational use). Workstations and applications designed for them are used by small engineering companies, architects, graphic designers, and any organization, department, or individual that requires a faster microprocessor, a large amount of random access memory (RAM), and special features such as high-speed graphics adapters. Historically, the workstation developed technologically about the same time and for the same audience as the UNIX operating system, which is often used as the workstation operating system. Among the most successful makers of this kind of workstation are Sun Microsystems, Hewlett-Packard, DEC, and IBM.

Network Interface Cards (NICs)

A network interface card (NIC) is a circuit board or card that is installed in a computer so that it can be connected to a network. A network interface card provides the computer with a dedicated, full-time connection to a network. Personal computers and workstations on a local area network (LAN) typically contain a network interface card specifically designed for the LAN transmission technologyNICs—sometimes called network cards—are the mechanisms by which computers connect to a network.

HUBHub is one of the basic icons of networking devices which works at physical layer and hence connect networking devices physically together. Hubs are fundamentally used in networks that use twisted pair cabling to connect devices.A hub is a common connection point for devices in a network. Hubs are commonly used to connect segments of a LAN.

Switches

A network switch (also called switching hub, bridging hub, officially MAC bridge) is a computer networking device that connects devices together on a computer network, by using packet switching to receive, process and forward data to the destination device.

Twisted pair wire

    Twisted Pair Cable is one of the most commonly used communication media. It consists of a copper wires. These wires are covered by insulating material (such as plastic). The wires are twisted around each other. Twisting of wires protect them from interference by external electromagnetic waves.

Coaxial cableCoaxial cable is also called Coax. It consists of a copper wire, which is called the inner conductor. Usually, the inner conductor is surrounded by three layers:

An insulting material, which covers the inner conductor.

The insulted inner conductor is surrounded by copper shield called outer conductor.

An insulting material, which covers the outer conductor.

FIBER OPTIC CABLE    The fiber optic cable uses light to transmit data. It consists of a very narrow strand or fiber of glass called the core. It is as thin as a human hair. The core is surrounded by a concentric layer of glass called cladding. The cladding is further protected by plastic coating called the Jacket. An important characteristic (or property) of fiber optic is refraction. Refraction is the characteristic of a material to either pass or reflect light.