Computer communications and networking Flashcards
What is a network?
A collection of connected computers plus their peripherals
What is a device on a network called?
Node
What is a LAN?
Local area network
What is a WAN?
Wide area network
Advantages of a LAN
- Makes data sharing easier
- Makes backups easier
- Computers are easily updated/reconfigured
- Computers can be monitored easily
- Users can communicate with each other
Disadvantages of a LAN
- Specialist staff needed for maintenance
- Network problems could affect all users
- Security may be a problem because data is accessible from many places
Differences between a LAN and WAN
- A LAN is confined to one site
- A LAN is owned and maintained by a single organisation but a WAN may not
What is a network interface controller (NIC)?
A device that generates and receives suitable electrical signals. It holds the MAC address of each node.
What is a MAC address?
Media access control address.
Allows a node on a network to be identified.
What are fibre-optic cables?
Cables that transmit data using light waves
What is a network hub?
Hardware that connects many network devices together into a single network segment.
A signal arriving at one is transmitted to all others
What are switches? (No, not the lightbulb switches)
Devices that connect multiple network segments or devices.
Messages are only sent to the intended device
What is the difference between hubs and switches?
Hubs transmit a message to all devices connected to it
However
Switches transmit a message to an intended device
What are bridges?
Devices that connect more than one network together
What are wireless access points?
Devices often connected to a router which allow a connection to a LAN without the need for cables
What features do wireless access points have to protect them from security risks?
- encryption
- hiding their broadcast identities
- allowing access to only certain MAC addresses
What is a router?
A device that receives data in the form of packets and forwards them to their destination.
What is a client-server network?
Where one or more servers provide services to many client machines where the users work