Networks
Broadband: a high speed connection to the internet
Bandwidth: the amount of data that can fit through an internet connection. Bandwidth is measured in Kbps and Mbps
Download: the transfer of data from a central computer to your computer
Upload: the transfer of data from your computer to a central computer e.g. an ISP
ISP: a company that provides access to the internet
Reasons for having for example a home network include:
Ethernet (Local Area Networks)
Ethernet: a set of rules or protocol for linking computers together to form a LAN. Ethernet networks may be cable or wireless networks. To create a network, you need a router. Each computer or device on the network is assigned an IP address by the router. The router uses this address to send data e.g. web pages to different computers and devices on the network.
There are two main types of Ethernet network, Cable and Wireless Networks.
Cable
Cable: Often referred to as Cat5 or Cat5e. Cable is connected to Network Interface Cards (NIC’s) on the computers, the plug for which is very similar as those that are used to connect telephones. The fastest Ethernet connection available is Gigabit which is 1000Mb (1 billion bits per second)
Advantages of using Ethernet cable networks are:
Disadvantages of using Ethernet cable networks are:
Wireless Networks
Wireless (Wifi): A network where computers communicate by radio or microwaves. Wifi network transmission speeds are up to 54Mbps
Advantages of using Wifi networks are:
Disadvantages of using Wifi networks are:
Powerline networks: Use existing mains power circuits for data transmission
Wireless Network Security
Broadband: a high speed connection to the internet
Bandwidth: the amount of data that can fit through an internet connection. Bandwidth is measured in Kbps and Mbps
Download: the transfer of data from a central computer to your computer
Upload: the transfer of data from your computer to a central computer e.g. an ISP
ISP: a company that provides access to the internet
Reasons for having for example a home network include:
- Share printers
- Share files e.g. music or pictures
- Share an internet connection between different computers and devices
Ethernet (Local Area Networks)
Ethernet: a set of rules or protocol for linking computers together to form a LAN. Ethernet networks may be cable or wireless networks. To create a network, you need a router. Each computer or device on the network is assigned an IP address by the router. The router uses this address to send data e.g. web pages to different computers and devices on the network.
There are two main types of Ethernet network, Cable and Wireless Networks.
Cable
Cable: Often referred to as Cat5 or Cat5e. Cable is connected to Network Interface Cards (NIC’s) on the computers, the plug for which is very similar as those that are used to connect telephones. The fastest Ethernet connection available is Gigabit which is 1000Mb (1 billion bits per second)
Advantages of using Ethernet cable networks are:
- More secure than wifi
- Quick transmission speeds
Disadvantages of using Ethernet cable networks are:
- Expensive to install e.g to install cables in walls
Wireless Networks
Wireless (Wifi): A network where computers communicate by radio or microwaves. Wifi network transmission speeds are up to 54Mbps
Advantages of using Wifi networks are:
- Can access the signal anywhere e.g. the garden.
- Cheaper (and quicker) to install than cable networks
Disadvantages of using Wifi networks are:
- Signal can be affected by household appliances
- Slower transmission speeds than cable networks
- Less secure than cable networks
Powerline networks: Use existing mains power circuits for data transmission
Wireless Network Security
When connecting to a wireless network using a Windows computer, you often see the window above which tells you:
The unique name (or SSID) of each wireless network
The signal strength for the network (in bars)
Which network you are currently connected to
Which networks are secured and which are not (see below)
To protect data on a network:
Encryption: Set up encryption e.g. WEP or WPA-PSK (WPA-PSK is the latest encryption standard and is the most secure). Encryption scrambles the data on your network meaning only computers with the correct encryption key can read it.
Router:
Change the default login details for the router – these are often set to admin and password
Install anti-virus software
Install firewall software
Storing and backing up data
Primary storage: Data saved on a computer. Primary storage devices include hard disks and solid state hard disks
Secondary storage: Data saved in a different place to a computer. Secondary storage devices include Flash memory, CDR’s, magnetic tape
Backup: A second copy of data
Online data storage: A company that provides storage space for data to be backed up online
Advantages of online data storage include:
Data can be accessed anywhere in the world with an internet connection
Can usually be automated (does it by itself)
No need to employ someone to be responsible for data backup
Disadvantages of online data storage include:
Need an internet connection to access data
Download/upload speeds can be effected by the speed (bandwidth and latency) of an internet connection.
Why backup?
Data could be stolen
Data could become corrupt and unreadable
Human error – data could be deleted
Protecting data in case of disaster
Backup data
Use RAID technology
Fit surge protectors
Use Uninterrupted Power Supply (UPS)
The unique name (or SSID) of each wireless network
The signal strength for the network (in bars)
Which network you are currently connected to
Which networks are secured and which are not (see below)
To protect data on a network:
Encryption: Set up encryption e.g. WEP or WPA-PSK (WPA-PSK is the latest encryption standard and is the most secure). Encryption scrambles the data on your network meaning only computers with the correct encryption key can read it.
Router:
Change the default login details for the router – these are often set to admin and password
Install anti-virus software
Install firewall software
Storing and backing up data
Primary storage: Data saved on a computer. Primary storage devices include hard disks and solid state hard disks
Secondary storage: Data saved in a different place to a computer. Secondary storage devices include Flash memory, CDR’s, magnetic tape
Backup: A second copy of data
Online data storage: A company that provides storage space for data to be backed up online
Advantages of online data storage include:
Data can be accessed anywhere in the world with an internet connection
Can usually be automated (does it by itself)
No need to employ someone to be responsible for data backup
Disadvantages of online data storage include:
Need an internet connection to access data
Download/upload speeds can be effected by the speed (bandwidth and latency) of an internet connection.
Why backup?
Data could be stolen
Data could become corrupt and unreadable
Human error – data could be deleted
Protecting data in case of disaster
Backup data
Use RAID technology
Fit surge protectors
Use Uninterrupted Power Supply (UPS)