Networking

Topologies & Networking Components & LAN, WAN, MAN, PAN

Topologies

BUS Network

In a bus network all the workstations, servers and printers are joined to one cable (the bus). At each end of the cable a terminator is fitted to stop signals reflecting back down the bus.


Advantages

  • Easy to install
  • Cheap to install, as it doesn’t require much cable

Disadvantages

  • If the main cable fails or gets damaged the whole network will fail
  • As more workstations are connected the performance of the network will become slower because of data collisions
  • Every workstation on the network "sees" all of the data on the network – this is a security risk

Ring Network

In a ring network each device (workstation, server, printer) is connected to two other devices, this forms a ring for the signals to travel around. Each packet of data on the network travels in one direction and each device receives each packet in turn until the destination device receives it.


Advantages

  • This type of network can transfer data quickly, even if there are a large number of devices connected because the data only flows in one direction, so there won’t be any data collisions.

Disadvantages

  • If the main cable fails or any device is faulty then the whole network will fail.

Star Network

In a star network each device on the network has its own cable that connects to a switch or hub. A hub sends every packet of data to every device, whereas a switch only sends a packet of data to the destination device.



Advantages

  • Very reliable – if one cable or device fails then all the others will continue to work
  • High performing as no data collisions can occur

Disadvantages

  • Expensive to install as this type of network uses the most cable (network cable is expensive)

  • Extra hardware required (hubs or switches) which adds to cost

  • If a hub or switch fails all the devices connected to it will have no network connection

Networking Components

Switch

A network switch is a small hardware device that joins multiple computers together within one local area network (LAN).

Server

In computer networking, a server is a computer designed to process requests and deliver data to other (client) computers over a local network or the Internet.

Networked Printer

A printer connected to a wired or wireless network. It may be Ethernet enabled and be cabled to an Ethernet switch, or it may connect to a Wi-Fi (wireless) network, or both.

Networked Camera

Also called an IP camera, a network camera records images and sends the compressed versions over the network. Network cameras used in surveillance systems usually offer a browser interface so the camera can be remotely accessed and viewed over the Internet. Network Video Recorder (NVR) systems use network cameras.

Client

A client is a piece of computer hardware or software that accesses a service made available by a server. The server is often (but not always) on another computer system, in which case the client accesses the service by way of a network.

Network Access Point

An access point is a device, such as a wireless router, that allows wireless devices to connect to a network. Most access points have built-in routers, while others must be connected to a router in order to provide network access. In either case, access points are typically hardwired to other devices, such as network switches or broadband modems.

Wireless Access Point

Wireless access points (APs or WAPs) are special-purpose communication devices on wireless local area networks (WLANs). Access points act as a central transmitter and receiver of wireless radio signals. Mainstream wireless APs support Wi-Fi and are most commonly used to support public Internet hotspots and other business networks where larger buildings and spaces need wireless coverage.

LAN, WAN, MAN, PAN?

LAN (Local Area Network)

A local area network, or LAN, consists of a computer network at a single site, typically an individual office building. A LAN is very useful for sharing resources, such as data storage and printers. LANs can be built with relatively inexpensive hardware, such as hubs, network adapters and Ethernet cables.

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.

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.

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.