Structure of the Internet ( Topologies ) Flashcards
What is a standalone?
One computer, not connected to any other computing devices.
When is a network formed?
When you connect two or more computers together.
What are the two types of network?
- Wide Area Network ( WAN )
* Local Area Network ( LAN )
What is a local area network?
- Two or more computers connected together within a small geographical area.
- Consists of a number of computing devices on a single site, or in a single building, connected together by cables.
What can a LAN network consist of?
Number of PCs, printers and scanners and a central server.
What is a wide area network?
- One that relies on a third party carriers or connection.
* WANs are typically spread over a large geographical area.
What is a network topology?
Arrangement of the various computing devices which make up a computer network.
What is a bus topology?
- An arrangement where nodes are connected in a daisy chain by a single central communications channel.
- All computers are connected to a single cable, ends of the cable are plugged into a terminator.
what is a star topology?
- An arrangement where a central node or hub provides a common connection point for all other nodes.
- A star network has a central node, which may be a switch or computer which acts as a router to transmit messages.
What does a switch do?
- Keeps a record of the unique MAC address of each device on the network.
- Can identify which particular computer on the network it should send the data to.
- Sends each communication to the specific computer it is intended for
What are the contents of the star topology?
• A star network has a central node, which may be a switch or computer which acts as a router to transmit messages.
How does a bus network function?
- All nodes are connected to a single backbone cable.
- Each end of the backbone is connected to either a terminator or a computer which stops signals bouncing back.
- Each node is passive
- Data is sent in one direction at a time only
- Only one computer can transmit successfully at any one time.
What are the advantages of a bus topology?
- Inexpensive to install, as it requires less cable and does not require any additional hardware.
- Good for small networks
- Devices can be easily added.
What are the advantages of a star network?
- Easy to isolate problems
- Good performance
- More secure if a switch is used as data is sent only to the recipient
- Higher transmission speeds can give better performance than a bus network
- No problems with collisions of data since each station has its own cable to the server
- System is more secure as messages are sent directly to the central computer and cannot be intercepted by other stations
- Easy to add new stations without disrupting the network
- if one cable fails, only one station is affected, so it is simple to isolate faults.
What are the disadvantages of a star network?
- Can be expensive to set up because of the length of cable required
- Central device is point of failure
What is the physical topology of a network?
Actual design layout, defines how the devices are physically connected
What is the logical topology?
- Defines how devices communicate across the physical topologies.
- Shape of the path the data travels in, and describes how components communicate across the physical topology.
What is a key feature of physical and logical topologies?
They are independent of each other
What is Wi-Fi?
- A wireless networking technology providing high speed internet and network connections.
- A local area wireless technology that enables you to connect to a device such as a PC.
How do devices connect to the internet?
Via a wireless network access point, WAP
What does a station consist of?
- A computer and an NIC
* An NIC is a wireless network interface card.
What does a WAP require?
A connection to a router, and the router requires a connection to a MODEM.
What does a wireless network require?
A wireless access point.
• This broadcasts on a fixed frequency, and all devices within range can connect.
