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Advantages of Twisted Pair Cable

(a) It is simple to use.
(b) It is inexpensive and does not require skilled personnel.
(c) It is less susceptible to electrical interference caused by nearby equipment or wires in a
telephone system. Signals can travel several kilometres without amplification when twisted
pair wires are used.

(d) These media can be used for both analog and digital data transmission. The bandwidth
depends on the thickness of the wire and the distance travelled, but several megabits per
second can be achieved for a few kilometres in many cases.
(e) If a portion of a twisted pair cable is damaged, the entire network is not shut.

Disadvantages of Twisted Pair Cable

(a) STP wire is physically larger and more expensive than twisted pair wire.
(b) STP is more difficult to connect to a terminating block.

(c) It easily picks up noise signals which results in higher error rates when the line length
exceeds 100 metres.
(d) Being thin in size, it is likely to break easily.

(e) It can support 19,200 bps up to 50 feet on RS-232 port.
2. Coaxial Cable

A coaxial cable is generally called a coax wire. It consists of
insulated copper wires surrounded by a braided metal shield
and covered in a plastic jacket. Coax cables are capable of
carrying higher frequency signals than that of twisted pair
cables. The wrapped structure provides it a good shield
against noise and crosstalk. Coaxial cables provide high
bandwidth rates of up to 450 mbps. Coaxial cable also comes
in two primary physical types: thin coaxial cable and thick Fig. 8.27: Twisted Pair Cable

coaxial cable. There are three categories of Coax cables,
namely RG-59 (Cable TV), RG-58 (Thin Ethernet) and RG-11 (Thick Ethernet). RG stands for Radio
Guide. Coax cables are widely used for internet connections and cable televisions.
Advantages of Coaxial Cable

(a) Coaxial cable can support greater cable lengths between network devices than twisted pair
cable.
(b) It is useful for transmitting analog as well as digital data across the network. For analog
data transmission, 75 ohm broadband coaxial is used and for digital transmission, 50 ohm
baseband cable is used.
Computer Networks
(c) It is widely used for cable television and internet connections.
(d) Coax are used for transmitting several channels simultaneously, i.e., they are helpful in
broadband transmission.
(e) Coaxial cable has excellent noise immunity because of thick covering outside the insulated
wires.
8.25