Guided Transmission Media in Computer Networks

Types of guided transmission media with their advantages and disadvantages.

1. Guided Transmission Media

2. Guided transmission media in computer networks refer to physical pathways that guide the data signals along a specific path. These media involve the use of cables or wires to transmit data between devices. The three main types of guided transmission media are 1. Twisted-pair cables 2. Coaxial cables 3. Fiber-optic cables.

3. 1. Twisted-Pair Cables Description: Twisted-pair cables consist of pairs of insulated copper wires twisted together. The twisting helps to reduce electromagnetic interference from external sources and crosstalk between adjacent pairs. Types: Unshielded Twisted Pair (UTP): The most common type used in networking, particularly in Ethernet cables (e.g., CAT5, CAT6). Shielded Twisted Pair (STP): Similar to UTP but with an additional shielding layer to reduce interference. Applications: Widely used in local area networks (LANs), telephone systems, and other short-distance communication systems.

4. Advantages: Cost-effective: Generally cheaper than other guided media. Flexible and easy to install: UTP cables are lightweight and can be easily routed through walls and ceilings. Widely supported: Compatible with many network devices and standards. Disadvantages: Limited bandwidth and distance: UTP cables have lower bandwidth compared to coaxial and fiber-optic cables, making them less suitable for high-speed or long-distance communication. Susceptible to interference: Although twisted pairs reduce interference, UTP is still more susceptible to electromagnetic interference (EMI) than shielded cables or fiber optics. Signal attenuation: Over long distances, signal degradation (attenuation) can occur.

5. 2. Coaxial Cables Description: Coaxial cables consist of a central copper conductor surrounded by an insulating layer, a metallic shield, and an outer insulating layer. The shielding provides better protection against electromagnetic interference. Types: Thicknet (10Base5): Used in older Ethernet networks, capable of longer distances. Thinnet (10Base2): A thinner and more flexible version used in some older LANs. Modern Coaxial: Used for cable television, broadband internet, and other communication systems. Applications: Used in cable television networks, broadband internet connections, and older Ethernet networks.

6. Advantages: Higher bandwidth: Supports higher data rates than twisted-pair cables. Better shielding: Provides better protection against interference and crosstalk. Longer distance: Can transmit signals over longer distances without significant attenuation compared to twisted-pair cables. Disadvantages: Bulkier and less flexible: Coaxial cables are thicker and less flexible than twisted-pair cables, making them harder to install in tight spaces. More expensive: Coaxial cables are generally more expensive than twisted-pair cables. Decreasing use in LANs: With the advent of faster Ethernet standards and fiber optics, coaxial cables are less commonly used in modern LANs.

7. 3. Fiber-Optic Cables Description: Fiber-optic cables transmit data as pulses of light through thin strands of glass or plastic fibers. They consist of a core (which carries the light signals), cladding (which reflects light back into the core), and a protective outer jacket. Types: Single-mode fiber (SMF): Has a small core that allows only one light mode to propagate, ideal for long-distance communication. Multi-mode fiber (MMF): Has a larger core that allows multiple light modes to propagate, suitable for shorter distances. Applications: Used in high-speed data networks, internet backbone connections, and long-distance telecommunications.

8. Advantages: Extremely high bandwidth: Fiber-optic cables can support very high data rates, making them ideal for high-speed networks. Long-distance transmission: Can transmit data over much longer distances without significant signal loss compared to copper cables. Immunity to electromagnetic interference: Because they use light, fiber-optic cables are not affected by electromagnetic interference or radio-frequency interference. Disadvantages: High cost: More expensive to install and maintain than copper-based cables. Fragility: Glass fibers are more delicate and prone to damage from bending or mishandling. Complex installation: Requires specialized equipment and skills for installation and splicing.

9. Thankyou Made By Sukanya Rakshit