Computer Science Project Communication and Network concepts Presented by: Poorvaja Jincy Abhishek

Contents Transmission media Data communication terminologies. twisted pair cable coaxial cables optical fibers Microwave Radio wave Satellite Data communication terminologies.

Transmission Media Transmission media is also known as communication channels. They are the cables that connect two or mare workstations. Two categories: 1.guided media-include cables. 2.unguided media-include waves through air, water or vacuum.

Twisted pair cable Common form of wiring in data communication application. Voice grade medium(VGM)-basis for telephone wiring. Consists of two identical wires wrapped together in a double helix. Twisting of wires reduces crosstalk

Types Unshielded twisted pair cable(UTP) Shielded twisted pair cable(STP)

Easy install & maintain Advantages Simple Easy install & maintain Physically flexible Low weight Easily connectable Inexpensive

Disadvantages Incapable of carrying signal over long distances due to high attenuation. Low bandwidth capabilities-unsuitable for broadband applications. max. data rates = 1 Mbps- without conditioning 10 Mbps with conditioning

Coaxial Cables Consists of a solid wire core surrounded by one or more foil or wire shields, each separated by a insulator. Inner core- carries signal Shield –provides the ground Suitable for high speed communication & widely used for TV signals. Types Thicknet-can be upto 500 meters long. They are thicker than thinnet Thinnet-using this cable max. distance of 185 meters can be joined.

Advantages Disadvantage Can be used as the basis for a shared cable network. Can be used for broadband transmission. Offer higher bandwidths- upto 400 MBPS. Disadvantage Expensive. Not compatible with twisted pair cable.

Optical fibers Consists of thin strands of glass or glass like material. Light source –LEDs or laser diodes(LDs). Bandwidth is very high. Fiber cable consists of three pieces: core Cladding Protective coating Types Single node Multi node

Advantages Immune to electrical and magnetic interference. Highly suitable for harsh industrial environments. Guarantees secure transmission and high transmission capacity. Can be used for broadband transmission where several channels are handled in parallel.

Disadvantages Installation problem- very fragile Connection looses are common problems. Cables are more difficult to solder. Light can reach the receiver out of phase. Virtually impossible to tap due to noise immunity. Most expensive.

Comparison Table Type Type Sub type Max.Segment Length Bandwidth supported installation cost Interference Twisted pair cable UTP STP 100 mts 100 Mbps 500 Mbps Easy moderate Cheapest High Coaxial cable Thinnet Thicknet 185 mts 500 mts 10 Mbps hard Cheap Moderate Low Fiber optic cable Multinude Singlenode 2 kms 100 kms 2 Gbps Very hard Expensive None

Guided media The different types of guided media are : Microwave Radio wave Satellite The different types of other unguided media are : Infrared Laser

cheaper Freedom from acquisition rights and other governmental requirements Ease of communication Ability to communicate through oceans No use of cables Micro wave advantages

Microwave disadvantages insecure Susceptible to weather Effects like rain Cost of design high Implementation tricky Antenna may split up in different pathway Microwave disadvantages

Radio wave advantages Cheaper Offers mobility Offers ease of communication Freedom from land acquisition rights disadvantages Reduce signal strength Insecure communication

Satellites advantages Area coverage is large Maintenance easy Can cover large areas of the earth Useful in sparsely populated areas c loses Disadvantages High atmospheric loses High investment costs Satellites advantages

Satellite disadvantages Over crowding of bandwidths High investments cost High atmospheric losses

other unguided media Infrared It uses infrared lights Used in everyday life like remotes , automotive garage doors and wireless speaker Common in pda’s Laser It is a line of sight transmission Point to point transmission It can be adversely affected by weather

IMPORTANT CONCEPTS TO BE KNOWN A channel is the medium which is used to carry information or data from one point to another. DATA CHANNEL It is the unit of measurement for the Info. Carrying capacity of a communication channel This baud is synonymous with BPS another unit Of measuring data transfer rates. BAUD It refers to the speed at which data transfer is measured. It is generally used to measure the speed of information through a high speed phone lines or modems. BITS PER SECOND

Acknowledgement First and foremost, we would like to thank Kiran madam for having given us the opportunity for expressing our ideas through this project. We would also like to thank our friends for their creative ideas without which this would have been incomplete, last but not the least, we would like to thank everyone who directly or indirectly supported us.