Transmission Media

What is Coaxial Cable? 

It is used by cable operators but sometimes ago it also used by telephone companies. Coaxial cable is a type of cable that has an inner conductor surrounded by an insulating layer, surrounded by a conductive shielding. Many also have an insulating outer jacket the diagram below illustrates the construction of a typical cable. Electrical signal flows through the center conductor.

Table. Common coaxial cable types and uses. There are many additional RG designations, as well as variations within each number class. 

Cable type	Ω	Use
RG-6	75	Video, TV
RG-8	50	Radio, computer
RG-11	75	Long runs
RG-58	50	Radio, computer
RG-59	75	Video, TV

 

Advantages:

1. Coaxial cable can support greater cable lengths between network devices than twisted pair cable.

2. Thick coaxial cable has an extra protective plastic cover that help keep moisture away and stronger.

Disadvantages:

1. Thick coaxial is not bend easily so, it is difficult to install.

2. Difficult to troubleshoot a simple issue.


What is Twisted Pair Cable?

Twisted pair cable consists of a pair of insulated wires twisted together. It is a cable type used in telecommunication for very long time. Cable twisting helps to reduce noise pickup from outside sources and cross-talk on multi-pair cables.

The most commonly used form of twisted pair is unshielded twisted pair (UTP). It is just two insulated wires twisted together. any data communication cables and normal telephone cables are this type. Shielded twisted pair (STP) differs from UTP in that it has a foil jacket that helps prevent cross-talk and noise from outside source. In data communications there is a cable type called FTP (foil shielded pairs) which consists of four twisted pair inside one common shield (made of aluminum foil). The following are the cable types specified in ANSI/TIA/EIA which are mention below:

Category 1: Cat 1 cable was originally designed for voice telephony only, but thanks to some new techniques, long-range Ethernet and DSL, operating at 10Mbps and even faster, can be deployed over Cat 1.

Category 2: Cat 2 cable can accommodate up to 4Mbps and is associated with token-ring LANs.

Category 3: Cat 3 cable operates over a bandwidth of 16MHz on UTP and supports up to 10Mbps over a range of 330 feet (100 m). Key LAN applications include 10Mbps Ethernet and 4Mbps token-ring LANs.

Category 4: Cat 4 cable operates over a bandwidth of 20MHz on UTP and can carry up to 16Mbps over a range of 330 feet (100 m). The key LAN application is 16Mbps token ring.

Category 5: Cat 5 cable operates over a bandwidth of 100MHz on UTP and can handle up to 100Mbps over a range of 330 feet (100m). Cat 5 cable is typically used for Ethernet networks running at 10Mbps or 100Mbps. Key LAN applications include 100BASE-TX, ATM, CDDI, and 1000BASE-T. It is no longer supported, having been replaced by Cat 5e.

Category 5e: Cat 5e (enhanced) operates over a bandwidth of 100MHz on UTP, with a range of 330 feet (100 m). The key LAN application is 1000BASE-T. The Cat 5e standard is largely the same as Category 5, except that it is made to somewhat more stringent standards. Category 5e is recommended for all new installations and was designed for transmission speeds of up to 1Gbps (Gigabit Ethernet). Although Cat 5e can support Gigabit Ethernet, it is not currently certified to do so.

Category 6: Cat 6, specified under ANSI/TIA/EIA-568-B.2-1, operates over a bandwidth of up to 400MHz and supports up to 1Gbps over a range of 330 feet (100 m). It is a cable standard for Gigabit Ethernet and other network protocols that is backward compatible with the Cat 5/5e and Cat 3 cable standards. Cat 6 features more stringent specifications for crosstalk and system noise. Cat 6 is suitable for 10BASE-T/100BASE-TX and 1000BASE-T (Gigabit Ethernet) connections.

Category 7: Cat 7 is specified in the frequency range of 1MHz to 600MHz. ISO/IEC11801:2002 Category 7/Class F is a cable is based on four twisted copper pairs, features even more stringent specifications for crosstalk and system noise than Cat 6.

Advantages: 

1. Cheaper and far easier to splice
2. Less susceptible to electrical interference caused by nearby equipment or wires.
3. In turn are less likely to cause interference themselves.
4. Because it is electrically "cleaner", STP wire can carry data at a faster speed.

Disadvantages: 

1. STP wire is that it is physically larger and more expensive than twisted pair
wire.
2. STP is more difficult to connect to a terminating block.

 

What is Fiber Optic or Optical fiber Cable?

A fiber optic cable is a network cable that contains strands of glass fibers inside an insulated casing. They're designed for long distance, very high-performance data networking and telecommunications.

Compared to wired cables, fiber optic cables provide higher bandwidth and can transmit data over longer distances. Fiber optic cables support much of the world's internet, cable television and telephone systems.

Advantages:

1. One single mode fiber can replace a metal of time larger and heavier.

2. Multi-mode optical cable has a larger diameter and can be used to carry signal

over short distance.

Disadvantages:

1. Fiber optic versus metal cable is that it is difficult to make connections to

fiber optic cable.

2. The optical fiber must be highly polished to allow light to pass with little loss.