LEARNING OBJECTIVES
-
Know and understand the different types of hardware required to build a network.
SUCCESS CRITERIA
Success Criteria:
-
Identify and differentiate between different hardware devices used to build a network.
-
Be able to build a working network using a number of devices.
1.4 Wired and Wireless Networks
Learners should have studied the following:
-
types of networks:
LAN (Local Area Network)
WAN (Wide Area Network) -
factors that affect the performance of networks
-
the different roles of computers in a client-server and a peer-to-peer network
-
LO4 - the hardware needed to connect stand-alone computers into a Local Area Network:
wireless access points
routers/switches
NIC (Network Interface Controller/Card)
transmission media -
the internet as a worldwide collection of computer networks:
DNS (Domain Name Server)
hosting the cloud -
the concept of virtual networks.
KEYWORDS
Network Interface Card (NIC) - A card that enables devices to connect to a network.
Wireless Access Point -is a networking hardware device that allows a Wi-Fi compliant device to connect to a wired network.
Networks - LESSON 3
Hardware to connect a network
Most LANs have traditionally been connected by means of copper wire. This allows fast and reliable data transmission. The wire is usually UTP (unshielded twisted pair), which provides fast data transmission and minimal interference. UTP cable is thin and flexible, which makes it relatively easy to install.
lo4- Transmission Media
Coaxial cable is a type of cable that has a central wire that is surrounded by an insulating layer. Many coaxial cables then have a final outer layer that acts like a jacket. This type of cable is mostly used in Ethernet.
Twisted cable is a type of cable that has two separately insulated wires wrapped around each other inside an outer layer. This is the most common type of cable that is used in network.
Fibre-optic cable is a type of cable that has lots of very fine glass threads inside an outer layer. Many networks are slowly replacing their cables with fibre-optic cables as it carries data much faster than other media.
Twisted cable
Fibre-optic cable
Coaxial Cable
lo4-Network interface card
As well as transmission media, a computer will need some way of connecting the transmission media to the computer so that data can be transmitted around the network. The component that is required for this is called a network interface controller , or card (NIC). A NIC is a circuit board that is installed into a computer to allow it to be connected to a network.
A computer can also be fitted with a wireless network
interface controller (WNIC) to allow a computer to be
connected wirelessly to a network.
In order for computers to connect wirelessly to a network, the network will need to have wireless access points (WAP). A WAP is a network hardware device that has Wi-Fi capabilities to connect to the network. In many home networks the WAP is built into the router.
A router is a hardware device that is essential for connecting computer networks together. It is the device that is used to connect our devices at home to the Internet. It is responsible for forwarding packets of data from one network to another network. A router will scan a packet of data that enters the device to see whether its destination is the network that it is currently travelling in or another network. It will the forward the packet on to its destination.
Hubs are less common these days on large enterprise networks. Home users sometimes get small hubs to connect a few devices because they are cheaper than switches or routers and require no setting up.
Hubs receive signals from a device and rebroadcast them indiscriminately to all connected nodes. They do not have any routing tables and they have no means of deciding where to send data. Hubs also switch the available bandwidth between any connected computers so they slow down network traffic.
A switch also connects computers together but a switch sends packets of data only to the intended destination, not to every connected node. Switches are usually self learning so that they build up a table of connected devices and use this to route data packets to their correct destination.
Switches are more expensive than hubs but they vary in cost according to their capabilities. The number of ports built into a switch can make a difference to its performance because the throughput of data may be divided between them.
Switches usually work at a higher capacity than the ethernet transmission medium, which is traditionally 10 Mbps (megabits per second). Modern installations are more likely to be gigabit ethernet (GbE), which can transmit ethernet frames at a rate of a gigabit per second (1 000 000 000 bits per second).
lo4- Router
lo4-Switch
