4.9.2 Networking Notes Flashcards
What is the topology?
The structure of the network.
What are the two types of topology?
- Physical network topology
* Logical network topology
What is the physical network topology?
• Actual architecture of the network.
How is a physical star network laid out?
Each client ( that is a device connected to the hub ) has its own direct connection to the central hub. The hub receives packets for all of the clients connected to it and is responsible for delivering them to the correct recipient.
How can a server be added to the physical star network?
The server can be added to the network in the same way that clients are connected to the central hub.
What are the advantages of a star network topology?
- Packets are sent directly to their recipient over a cable that is connected only to the recipient. Other clients on the network cannot see packets that aren’t intended for them
- It is easy to add and remove clients to and from the network
- Each cable has just one device communicating over it, eliminating the possibility of collisions
- The failure of the cable does not affect the performance of the rest of the network
What are the disadvantages of a star network topology?
- Should the central hub fail, all communication over the network is stopped
- Expensive to install thanks to the amount of cable required.
What is a physical bus?
- A physical bus connects clients to a single cable called a backbone.
- A device called a terminator is placed at either end of the backbone.
Where are central hubs present in the physical bus topology?
There is no need for a central hub in a bus topology, and a server can be connected to the backbone just like a client.
What are the advantages to the bus topology?
- No central hub, reducing the chances of a network failure and decreasing the cost of installation
- Inexpensive to install as a minimum length of cable is required
What are the disadvantages of a bus topology?
- Packets are sent through the shared backbone allowing every client on the network to see packets that aren’t intended for them
- The backbone is used for communication by multiple clients, introducing the risk of collisions.
- Should the backbone fail, the entire network becomes unusable.
What is a logical topology?
The flow of data packets within a network.
What is the logical difference between a bus and a star?
Logical bus network delivers packets to all clients on the network whereas a logical star network delivers packets only to their recipient.
How may topologies be mixed?
If a network is set up as a physical star, it can still behave as a logical bus.
What does running a bus protocol allow for?
Running a bus protocol on the hub allows it to distribute packets to all of the connected clients so as to act like a bus network.