Guided media, also known as bounded media, refers to the transmission medium that guides the data signals along a specific path.
• These media are physical links between the transmitter and receiver and include cables such as twisted pair, coaxial, and fiber-optic cables.
1.) Twisted Pair Cable
Twisted pair cable is a type of guided media that consists of pairs of insulated copper wires twisted together. The twisting helps to reduce electromagnetic interference and crosstalk between adjacent pairs.
Types:
1.) Unshielded Twisted Pair (UTP):
Commonly used in Ethernet networks, phone systems, and many other applications. It lacks additional shielding, making it more flexible and less expensive.
2.) Shielded Twisted Pair (STP):
Similar to UTP but includes an additional shielding (foil or braid) to reduce interference. It is used in environments with high interference.
Characteristics:
- Bandwidth: Varies by category (e.g., Cat5e, Cat6, Cat7), typically supporting up to 10 Gbps for short distances.
- Distance: Effective for short to medium distances (up to 100 meters for Ethernet).
- Cost: Relatively low cost.
- Installation: Easy to install and manage.
Applications:
- Local Area Networks (LANs)
- Telephone networks
- Security camera systems
2.) Coaxial Cable
Coaxial cable is type of guided media that consists of a central conductor surrounded by an insulating layer, a metallic shield, and an outer insulating layer. This design provides better protection against interference.
Characteristics:
- Bandwidth: Higher bandwidth than twisted pair cables, suitable for high-frequency signals.
- Distance: Can transmit signals over longer distances without significant loss compared to twisted pair cables.
- Cost: More expensive than twisted pair cables.
- Installation: More difficult to install due to stiffness and bulkiness.
Applications:
- Cable television (CATV)
- Broadband internet
- Long-distance telephone transmission
- CCTV systems
3.) Fiber-Optic Cable
Fiber-optic cable is type of guided media that uses light to transmit data. It consists of a core made of glass or plastic fibers, surrounded by a cladding that reflects light back into the core, and an outer protective layer
Characteristics:
- Bandwidth: Extremely high bandwidth, capable of transmitting large amounts of data at very high speeds (up to several Tbps).
- Distance: Can transmit data over very long distances without significant signal loss (up to 100 kilometers or more).
- Cost: More expensive than both twisted pair and coaxial cables, but prices are decreasing with technological advancements.
- Installation: More complex and delicate installation process.
Applications:
- Internet backbone
- Long-distance telecommunications
- High-speed data networks
- Medical imaging and lighting
