Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
22 Cards in this Set
- Front
- Back
- 3rd side (hint)
|
What are the characteristics of a network and what are the 2 main types? |
It has 2 or more computers connected together with the ability to transmit data between each other. The 2 types are LAN and WAN. |
|
|
|
What is a LAN? |
LAN stands for local area network; it is spread over a small geographical area or a single site. |
Example: a networking at a school or at home |
|
|
What is a WAN? |
WAN stands for wide area network; it is spread over a large geographical area. |
Example: a networking covering a country |
|
|
What is a physical topology? |
It's the physical layout of the wires and components which form the network. |
Examples: bus, star, mesh |
|
|
What is a logical topology? |
It's the layout which shows how data flows. |
|
|
|
What is a physical bus topology? |
- all devices are connected to a backbone cable which the ends of it are connected to a terminator. |
|
|
|
What are the advantages of a bus topology? |
- inexpensive - no additional hardware required |
|
|
|
What are the disadvantages of a bus topology? |
- if the cable fails, the entire network gets disconnected - as traffic increases, performance decreases - all computers can see the data transmission - low security |
|
|
|
What is a physical star topology? |
It has a central node (switch). It keeps record of the unique MAC address of each device on the network and can identify which device it should send data to. |
|
|
|
What are the advantages of a star topology? |
- if one cable fails, only one station is affected (simple to find faults) - consistent performance even with heavy traffic - higher transmission speeds, giving better performance than a bus topology - can easily add new stations without disrupting the network - more secure as messages are sent directly to the central computer; cannot be intercepted by other stations |
|
|
|
What are the disadvantages of a star topology? |
- expensive due to the length of cable required -if the central switch fails, the rest of the network fails and data can no longer be transmitted to any of the nodes. |
|
|
|
What is a physical mesh topology? |
- every node is connected to every other node, by transmitting data across any intermediate nodes - only one node needs a connection to the Internet and all others can share this connection - most commonly found with wireless technology such as Wi-Fi |
|
|
|
What are the advantages of a mesh topology? |
- wireless: no cabling costs - as the number of nodes increases, the reliability and speed of the network increases - nodes are automatically incorporated into the network - nodes don't need to go through the central node so fast communcation/speed |
|
|
|
What are the disadvantages of a mesh topology? |
- wireless: devices with wireless capability must be purchased; cost increases - wired network: a large quantity of cable is required; expensive - maintaining the network is difficult |
|
|
|
What is a WAP? |
A wireless access point allows Wi-Fi devices to connect to a wired network. |
|
|
|
What are IP addresses? |
- An Internet Protocol address is a unique address that is assigned to a network device. - It indicates where a packet of data is to be sent/has been sent from. - Routers use this address to direct the data packet accordingly |
|
|
|
What is a URL? |
- A Uniform Resource Locator is a full address of an Internet resource. - specifies the location of a resource on the Internet, including resource name and usually file type so that a browser can request it from the website server. - "http" - method - "www" - host - "webpage" - location - "element" - resource |
http://www.domainname.com/folder/subfilder/webpage.html#element |
|
|
What is a MAC address? |
- Media Access Control - assigned to a NIC - unique |
|
|
|
What is a firewall? |
A security checkpoint designed to prevent unauthorised access between 2 networks. |
|
|
|
What does a typical firewall consist of? |
- a separate computer containing 2 NICs with one connected to the internal network and the other connected to the external network - each data packet that attempts to pass between the 2 NICs is analysed against packet filters then accepted or rejected |
|
|
|
What is a proxy server? |
- it intercepts all packets entering and leaving a a network, hiding the true network addresses of the source from the recipient. - enables privacy and anonymous surfing - maintains a cache of websites commonly visited and returnd the webpage data to the user immediately without needing tonreconect to the Interent and re-request the page from the web server. - speeds up user access to webpage data and reduces web traffic |
|
|
|
What are proxy servers used for? |
To filter requests providing administrative control over the content that users may demand |
Example: a school web proxy filtering undesirable/unsafe online content |
