1.3 Computer networks, connections and protocols Flashcards
What does the DNS convert?
Converts domain names into IP addresses for routers.
What is layering?
Dividing complex tasks of networking into smaller and simpler tasks that work well with each other.
What do both hardware and software have?
A defined responsibility.
What does each layer do?
Provide a service to the layer above it
twoWhat are three advantages of layering?
- Complexity of the problem is reduced into manageable sub-problems.
- Products from different companies are compatible.
What are three features of a LAN?
- Small geographical area
- Hardware is owned by the organisation using it
- LANs are wired with UTP cable, fibre optic or wireless using Wi-Fi
What are three disadvantages of networking?
- Increased security risks to data
- Lots of traffic from data causes the computer to run slower
What is bandwidth?
The amount of data that can be sent and received successfully in a given time.
Do wired or wireless connections have a higher bandwidth?
Wired
Do fibre optic or copper cables have a higher bandwidth?
Fibre optic
What does latency mean?
The delay from transmitting data to receiving it.
What is an example of something that causes latency and how does it cause latency?
Bottlenecks.
This can be caused by not using switches to appropriately segment traffic on a network.
What are four differences between a client-server model and a peer-to-peer model?
Client-server model:
- A client makes requests to the server for data and connections
- Controls access + security to one shared file store
Peer-to-peer model:
- A peer is a computer on a network. It is equal to all other peers
- Each peer is responsible for its own security and backup
What are three advantages of the client-server model?
- Easier to manage secuirty files
- Easy to take backups of all shared data
- Easy to install software updates to all computers
What are two disadvantages of the client-server model?
- Can be expensive to set up and maintain
- Server is a single point of failure
What is the rule for IPv4 address?
- 4 groups of denary numbers
- Separated by full stops
What is the rule for IPv6 address?
- 8 groups of hex numbers between 0 and FFFF
- Separated by colons
What is the format of a MAC address? (2)
- Usually presented in hex, denary or binary
- 48 bits long
- Separated by colons
(Explain) Why should an airport also allow the network to be accessed using a wireless connection? (3)
- Backup if the wired connection fails.
- Easier to connect more devices.
- Some devices can’t connect using a wired connection.
What is one benefit of an office using a star topology instead of a mesh topology?
Easier to add new nodes.
What is the role of the switch in a star topology? (3)
- Connects all the devices together in a network.
- Receives data from all devices in a network.
- Uses the MAC address of devices.
What are three things that affect the performance of a network?
- Bandwidth
- Latency
- Error rate
What is bandwidth?
The amount of data that is sent and received successfully in a given time.
What is latency?
The delay between data being sent and received.
What is error rate?
How many packets of data that don’t reach their destination.
