Write 2 pages thesis on the topic wireless communication. Running Header: WIRLESS Wireless Communication Mesh Topology Mesh topology or mesh network is a network topology in which devices are connecte

Write 2 pages thesis on the topic wireless communication. Running Header: WIRLESS Wireless Communication Mesh Topology Mesh topology or mesh network is a network topology in which devices are

connected with many redundant interconnections between network nodes. In a true mesh

topology every node has a connection to every other node in the network.

Advantages and Disadvantages

As all nodes are interconnected with each other hence mesh topology yields

greatest amount of redundancy, so in the event that one of those nodes fails, network

traffic can be directed to any of the other nodes. Since for full mesh network topology

every node must has a circuit connecting it to every other node in a network hence it is a

very expensive to implement.

Ring Topology

In ring topology all devices are connected to

one another in the shape of a closed loop, so that each

device is connected directly to two other devices, one

on either side of it.

Advantages and Disadvantages

Ring topologies are relatively expensive and

difficult to install, but they offer high bandwidth and

can span over large distances.Mesh

Star Topology Fig. 1 Star, Bus, Ring &

In star topology all devices are connected to aMesh Topologies

central hub.

Advantages and Disadvantages

Star networks are relatively easy to install and manage, but bottlenecks can occur

because all data must pass through the hub.

The above mentioned topologies are shown in fig.1 on page 2.

Ethernet

A most widely implemented local-area network (LAN) architecture developed by

Xerox Corporation in cooperation with DEC and Intel in 1976 is termed as Ethernet. It

uses a bus or star topology (as shown in fig. 1) and supports data transfer rates of 10

Mbps. A newer version of Ethernet called 100Base-T supports data transfer rates of 100

Mbps while the latest version, Gigabit Ethernet has data transfer rates of 1 gigabit (1,000

megabits) per second. The Ethernet specification served as the basis for the IEEE 802.3

standard, which specifies the physical and lower software layers. Ethernet uses the

Carrier Sense with Multiple Accesses with Collision Detect (CSMA/CD) access method

to handle simultaneous demands.

Token Ring

Token ring is a type of computer

network developed by IBM, in which all

the computers are arranged (schematically)

in a circle using ring topology. A token, which Fig. 2 Token Ring Network

is a special bit pattern, travels around the circle.

To send a message, a computer catches the token, attaches a message to it, and then lets

it continues to travel around the network. Token transmission does not depend on

CSMA/CD. Instead, all token ring hardware coordinates among all connected computers

to insure that transmission is passed to each computer in turn.

FDDI

Fiber Distributed Data Interface (FDDI) is a set of American National Standards

Institute (ANSI) and ISO standards for data transmission on fiber optic lines in a local

area network (LAN) that can extend in range up to 200 km (124 miles). The FDD

protocol is based on the Token Ring protocol. In addition to being large geographically,

an FDDI local area network can support thousands of users. FDDI is frequently used on

the backbone for a wide area network (WAN). An FDDI network contains two token

rings, one for possible backup in case the one for possible backup in case the primary

ring fails. The primary ring offers up to 100 Mbps capacity. If the secondary ring is not

needed for backup, it can also carry data, extending capacity to 200 Mbps. The single

ring can extend the maximum distance. a dual ring can extend 100 km (62 miles).

Wireless Networks

A network which is created through the connection of wireless access points

installed at each network users locale is called wireless network. It can has either star or

mesh or mesh topology. If all network users have access through an access point then

such wireless network works in star topology. If in wireless network each network user is

also a provider, forwarding data to the next node then such wireless network operates in

mesh network topology. In wireless mesh network the infrastructure is decentralized and

simplified because each node need only has to transmit for the next node.

TCP/IP

The TCP/IP layering model which is also called Internet Layering Model or the

Internet Reference Model contains five layers as illustrated in fig. 3. Although TCP/IP

reference model corresponds to layers of the OSI reference model, the OSI layering

scheme does not have a layer that corresponds to TCP/IP’s Internet Layer .

Fig. 3

Reference

Comer, D. E. (1997). Computer Networks and Internets. Upper Saddle River, New

Jersey: Prentice Hall

Tanenbaum, A. S. (1999). Computer Networks.