WHAT ARE THE TYPES OF COMPUTER NETWORK?

One way to categorize the different types of computer network designs is by their scope or scale. For historical reasons, the networking industry refers to nearly every type of design as some kind of area network.

Introduction to LANs, WANs, and Other Kinds of Area Networks

Common types of area networks are:

1. LAN - Local Area Network

                                                 LAN (LOCAL AREA NETWORK)

A LAN connects network devices over a relatively short distance. A networked office building, school, or home usually contains a single LAN, though sometimes one building will contain a few small LANs (perhaps one per room), and occasionally a LAN will span a group of nearby buildings. In TCP/IP networking, a LAN is often but not always implemented as a single IP subnet.

LANs are typically used for single sites where people need to share resources among themselves but not with the rest of the outside world. Think of an office building where everybody should be able to access files on a central server or be able to print a document to one or more central printers. Those tasks should be easy for everybody working in the same office, but you would not want somebody just walking outside to be able to send a document to the printer from their cell phone! If a local area network, or LAN, is entirely wireless, it is referred to as a wireless local area network or WLAN.

2. PAN - Personal Area Network

                                            PAN (PERSONAL AREA NETWORK)

A personal area network, or PAN, is a computer network organized around an individual person within a single building. This could be inside a small office or residence. A typical PAN would include one or more computers, telephones, peripheral devices, video game consoles and other personal entertainment devices.

This type of network provides great flexibility. For example, it allows you to:

• Send a document to the printer in the office upstairs while you are sitting on the couch with your laptop.
• Upload a photo from your cell phone to your desktop computer.
• Watch movies from an online streaming service to your TV.

3. MAN - Metropolitan Area Network

 

                                             MAN (METROPOLITAN AREA NETWORK)

A metropolitan area network, or MAN, consists of a computer network across an entire city, college campus or small region. A MAN is larger than a LAN, which is typically limited to a single building or site. Depending on the configuration, this type of network can cover an area from several miles to tens of miles. A MAN is often used to connect several LANs together to form a bigger network. When this type of network is specifically designed for a college campus, it is sometimes referred to as a campus area network, or CAN.

4. WAN  - Wide Area Network

A wide area network, or WAN, occupies a very large area, such as an entire country or the entire world. A WAN can contain multiple smaller networks, such as LANs or MANs. The Internet is the best-known example of a public WAN.

Sources:

https://study.com/academy/lesson/types-of-networks-lan-wan-wlan-man-san-pan-epn-vpn.html

https://www.lifewire.com/lans-wans-and-other-area-networks-817376

https://www.techopedia.com/definition/5079/personal-area-network-pan

What are the types of Cables?

Introduction to Network Cables

Despite advances in wireless technologies, many computer networks in the 21st century still rely on cables as a physical medium for devices to transfer data. Several standard types of network cables exist, each designed for specific purposes.

Types of Cables:

Twisted-pair Cable

• STP- Shielded Twisted Pair
• UTP- Unshielded Twisted Pair 

Coaxial Cable 

Fiber-optic Cable

                                                                                                                                                                

~Twisted Pair Cables ~

Twisted pair eventually emerged during the 1990s as the leading cabling standard for Ethernet, starting with 10 Mbps (10BASE-T, also known as Category 3 or Cat3), later followed by improved versions for 100 Mbps (100BASE-TX, Cat5, and Cat5e) and successively higher speeds up to 10 Gbps (10GBASE-T). Ethernet twisted pair cables contain up to eight (8) wires wound together in pairs to minimize electromagnetic interference


Two primary types of twisted pair cable industry standards have been defined: Unshielded Twisted Pair (UTP) and Shielded Twisted Pair (STP). Modern Ethernet cables use UTP wiring due to its lower cost, while STP cabling can be found in some other types of networks such as Fiber Distributed Data Interface (FDDI) 

Shielded Twisted Pair (STP)

Often used in “noisy” environments where a shield of metallic foil is wrapped around each of the wire pairs, with an additional overall shielding to protect against excessive electromagnetic interference.

UTP (Unshielded Twisted Pair)

               Is the most common form of twisted pair wiring.  It is less expensive and easier to work with than STP.

               Unshielded twisted pair (UTP) cables are widely used in the computer and telecommunications industry as Ethernet cables and telephone wires.

~Coaxial Cable~

     The standard media used by cable TV operators.

     It consists of a plastic insulator that separates the solid copper inner conductor and the woven, copper braid outer conductor.

Coaxial cable, or coax , is a type of electrical cable that has an inner conductor surrounded by a tubular insulating layer, surrounded by a tubular conducting shield. Many coaxial cables also have an insulating outer sheath or jacket. The term coaxial comes from the inner conductor and the outer shield sharing a geometric axis.

~Fiber-optic Cable~

has a reflective coating that allows light beams to travel without outer interference.

An optical fiber cable, also known as a fiber optic cable, is an assembly similar to an electrical cable, but containing one or more optical fibers that are used to carry light. The optical fiber elements are typically individually coated with plastic layers and contained in a protective tube suitable for the environment where the cable will be deployed.

Difference Between Straight Through and Crossover Cable

Ethernet cables can be wired as straight through or crossover. The straight through is the most common type and is used to connect computers to hubs or switches. They are most likely what you will find when you go to your local computer store and buy a patch cable. Crossover cable is more commonly used to connect a computer to a computer and may be a little harder to find since they aren’t used nearly as much as straight through cable. Then, what’s the difference between them? Difference between straight through and crossover cables will be introduced in this blog.

T568A And T568B Wiring Standard Basis
A RJ45 connector is a modular 8 position, 8 pin connector used for terminating Cat5e or Cat6 twisted pair cable. A pinout is a specific arrangement of wires that dictate how the connector is terminated. There are two standards recognized by ANSI, TIA and EIA for wiring Ethernet cables. The first is the T568A wiring standard and the second is T568B. T568B has surpassed 568A and is seen as the default wiring scheme for twisted pair structured cabling. If you are unsure of which to use, choose 568B.

What Is Straight Through Cable?
A straight through cable is a type of twisted pair cable that is used in local area networks to connect a computer to a network hub such as a router. This type of cable is also sometimes called a patch cable and is an alternative to wireless connections where one or more computers access a router through a wireless signal. On a straight through cable, the wired pins match. Straight through cable use one wiring standard: both ends use T568A wiring standard or both ends use T568B wiring standard. The following figure shows a straight through cable of which both ends are wired as the T568B standard.

What Is Crossover Cable?
An Ethernet crossover cable is a type of Ethernet cable used to connect computing devices together directly. Unlike straight through cable, crossover cables use two different wiring standards: one end uses the T568A wiring standard, and the other end uses the T568B wiring standard. The internal wiring of Ethernet crossover cables reverses the transmit and receive signals. It is most often used to connect two devices of the same type: e.g. two computers (via network interface controller) or two switches to each other.

Choose a Straight Through or Crossover Cable?
Usually, straight through cables are primarily used for connecting unlike devices. And crossover cables are use for connecting unlike devices alike devices.
Use straight through cable for the following cabling:

• Switch to router
• Switch to PC or server
• Hub to PC or server

Use crossover cables for the following cabling:

• Switch to switch
• Switch to hub
• Hub to hub
• Router to router
• Router Ethernet port to PC NIC
• PC to PC

Conclusion
Straight through and crossover cables are wired differently from each other. One easy way to tell what you have is to look at the order of the colored wires inside the RJ45 connector. If the order of the wires is the same on both ends, then you have a straight through cable. If not, then it’s most likely a crossover cable or was wired wrong. At present, the straight through cable is much more popular than crossover cable and is widely used by people. FS.COM provides a full range straight through Cat5e, Cat6, Cat6a and Cat7 Ethernet patch cables with many lengths and colors options. Look for Ethernet patch cables, just come to FS.COM!

Sources:

https://www.lifewire.com/introduction-to-network-cables-817868
https://www.techopedia.com/definition/13454/unshielded-twisted-pair-cable-utp
https://en.wikipedia.org/wiki/Optical_fiber_cable

http://www.cables-solutions.com/difference-between-straight-through-and-crossover-cable.html