Unit 5 Networks and Web Technologies
No description yet. This curated deck is ready for daily study.
Card preview (24)
What is the largest Network in the world?
The Internet
What is the Internet?
A network of inter-connected networks
What is the World Wide Web?
A collection of resources accessed via the Internet
What is the main part of the Internet known as?
The backbone
What is the Backbone of the Internet?
A set of dedicated connections that connect several large networks at various points on the globe. Each of these points are then connected to other regional networks, usually controlled by Internet Service Providers
What does an ISP do?
Internet Service Providers Provides access to individual end-users
What is an Internet Address?
Each device on a network needs to be uniquely identified so that data can be sent to the correct destination, much like an address on a letter
What is a URL stand for?
Uniform Resource Locator
What does a URL do?
Specifies the means of accessing a resource across a network and its location The protocol and the domain name of the resource together form the URL
What is a DNS?
Domain Name System Servers are dedicated computers with an index of domain names and their corresponding IP addresses
How many DNS servers work together to catalogue every domain name
13
Why do we not use IP addresses directly in a browser?
Because URLs are much more user friendly and easier to remember
What could happen when the DNS Server does not have a record for a specific domain? (2)
• It could recursively handle the request so that it can eventually deliver an IP address or print an error message • It could refer to a DNS server authoritative
Why must Domain Names be unique?
Because otherwise the DNS request could be confused
What are Internet Registries?
Organizations that control the allocation of domain names and IP addresses
How many global Internet Registries are there?
5
Who issues available Domain Names?
Internet Registries
What is a LAN?
Local Area Network Two or more computers connected together within a small geographical area
What is a WAN?
Wide Area Network A large network of information that is not tied to a single location
What is a Network Topology?
The 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
What are the advantages of a Bus Topology? (3)
• Inexpensive to set up • Devices can be easily added • Good for small networks
How does a Bus Topology work? (5)
• 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 the disadvantages of a Bus Topology? (4)
• Main cable is a point of failure • Limited cable length • Performance degrades with heavy use because of data collisions • Poor security