1.4 Wired and Wireless Networks Flashcards
What is a NETWORK?
Networks are multiple devices (computers) connected together to share resources
What is a local area network called?
LAN
What is a wide area network is called?
WAN
List 2 characteristics of LANs
- Covers small geographic areas
- Connected with a switch
List 2 things about WANs
- Cover a large geographic area
- Connects LANs together in a large geographical area
List 3 disadvantages of NETWORKS
- Malware and viruses spread very easily between computers
- Expertise is expensive requires lot of money
- Increased secured risk of data
Give an example of Network
Internet
The speed of a network is measured in …
Bit per Second
What does… mean
- Kbps
- Mbps
- Gbps
Kilobits per second
Megabit per second
Gigabits per second
Define “Bandwidth”
It describes how much data can be transferred over a connection in a given time.
List the 2 types of copper Ethernet cables
Cat-5 goes to 100Mbps (Slower)
Cat-6 goes to 1 Gbps (Faster)
Define how fiber optic cables work
Fiber optic cables are a lot faster and transfer data using light, Fiber is really expensive.
Define “Backbone”
A backbone is a part of computer network that interconnects various pieces of network.
Name the 2 radio bands of WiFi
2.4 and 5ghz
List 3 characteristics in Wired Network
- It’s more costly than Wi-Fi to install in a building
- Allows hundreds of people to log in at the same time
- It is immune to radio interference
What is a server?
A server is a special computer on a network that is not used as a work station but is a computer dedicated to serving files and managing services.
What is the name of the network that uses a server?
A network that uses a server is called client-server model.
What is the name of a network that doesn’t use a server?
A network that doesn’t uses a server is called peer to peer model.
List 3 characteristics of Client server
- Server controls access and security to one shared file store.
- A server runs a backup of data.
- Most larger local area networks will use a client server type
Advantages of Client server
- Easier to manage security of files.
- Easier to take backups of all shared data. (because is connected to the server)
- Easier to install software updates to all computers.
Disadvantages of Client server
- Can be expensive to set up and maintain.
- Requires IT specialists to maintain.
- The server is a single point of failure. User would lose access if the server fails.
- If it overloads, stops sharing files
List 3 characteristics of Peer to Peer server
- Peers serve their own files to each other.
- Each peer is responsible for its own security.
- Each peer is responsible for its own backup.
Advantages of Peer to Peer server
- Very easy to maintain. Specialist staff are not required.
- No dependency on a single computer. (No single point of failure)
- Cheaper to set up. No expensive hardware required.
Disadvantages of Peer to Peer server
- The network is less secure. (No single service area that authenticates users, each client will need to authenticate it themselves)
- Users will need to manage their own backups.
- Can be difficult to maintain a well ordered file store.(If peers are sharing files with each other)
What is a Wireless access point (WAP)?
- Allows for wireless devices to connect a network (either LAN or WAN) Includes connections through WI-FI and Bluetooth.
- They provide Internet in public places (often known as Wi-Fi hotspots) For example in a school.
Define “Router”
- A computer that is programmed to move data.
- An interconnection devise used on networks to connect two or more devices.
What do Routers contain?
Routers can contain a routing table which has a list of IP addresses and common routes for packets to take Routers examine packets IP addresses.
How does the Router share packets?
- The router will apply a subnet mask to identify a network and determine which network the packet should be forwarded to.
- If the packet is for this network - the router determines which host to send the packet to.
- Routers allow packets from different network types to be exchanged.
Define “HUB”
Is a common connection points for devices in a network. It is similar to a switch
Define “Switch”
Is an interconnection device that connects 2 or more devices together and helps in solving the issue of data collisions.
List 2 things that Switches do
- As a data packet arrives at the switch – its destination address is examined and the switch creates a direct connection to that device.
- It can cause more pressure in the bandwidth.
What is a “NIC”?
Network Interference Card
List the uses for NICs
- A network interference card allows a computer to connect to a wired network.
- A NIC allows data packets to travel to and from a computer.
- A NIC contains MAC address which is a physical hardware address.
- A NIC allows an Ethernet cable to be plugged into this.
What is a “MAC Address”?
Is an unique number that is in a hexadecimal format it is also static.
List the characteristics of “Packets”
- Data transmitted over a network is broken down into packets
- Each packet contains the address of the sender and the receiver (IP addresses)
- Packets will contain a sequence number
- Packets will have time to live (how many hops around the network they can take before they disappear)
What is DNS?
DNS (Domain Name Server) is a list of domain names and their associated IP addresses
What is the role of DNS?
All packets are transmitted as IP addresses - therefore to access the server that hold the OCR website - we would need to know the IP address
What does “http”do to a computer?
Tells the computer to use the hypertext transfer protocol, which puts the packets together to be use in a web browser
What does “www” mean?
Is a webpage and that it is located on the world wide web
What does “HOSTING” mean?
In order to let other people see your web site, it will be placed on a web server.
What does Hosting do?
- It would ensure that the domain name is unique and not already registered
- Each registered domain name would have an associated IP address – this would then be registered on a DNS
What is “The Cloud”?
The cloud or cloud computing refers to computing that is done outside of your local network
The Cloud is a network of servers, what are their jobs?
- Some servers will run applications
- Some servers will store data
List 3 benefits of the Cloud
- Increase storage e.g. from mobile phones
- Access files from anywhere in the world
- Collaborate with others from around the world
