1.3.4 Web Technologies pt2

Question 1

Index

Answer 1

A record of resources located on the world wide web

Question 2

Web crawler

Answer 2

Internet bots that continuously crawl the web to discover and record publicly available web pages
Creates an index that is searched for relevant content when you search

Question 3

Meta tags

Answer 3

A description of the content of a web page inside the HTML tags to make it more likely to be found

Question 4

PageRank uses

Answer 4

Ranks web pages based on how many web pages link to them and the amount of pages that link to those

Question 5

PR(A) formula

Answer 5

PR(A) = (1-d) + d(PR(Ti)/C(Ti) + … + PR(Tn)/C(Tn))

Ti -> Tn are all the pages that lead to a page so divide each page rank by the amount of outward links and sum

Question 6

d

Answer 6

Damping factor - probability of a user not opening that link

Question 7

C(Ti)

Answer 7

The number of outward links from page TI

Question 8

PageRank Process

Answer 8

Starting with each PageRank as 1, iterate the algorithm for each.
Keep iterating, feeding new values only at the end of each iteration (when every page has had PageRank run on it)

Question 9

Client-server

Answer 9

Clients on terminals access the central server to carry out tasks
Diagram has a central server connected to terminals by lines

Question 10

Client-server advantages

Answer 10

+ Secure
+ Can be used for small and large organisations
+ Complex tasks are performed quicker

Question 11

Client-server disadvantages

Answer 11

• Requires specialist IT staff to maintain (expensive)

- If the server breaks down no devices can be used

Question 12

Peer-to-peer architecture

Answer 12

Has no central server, processing is done by the client’s devices which are connected to each other
Diagram has terminals connected like in a full mesh topology

Question 13

Peer-to-peer advantages

Answer 13

+ Computers can communicate without going through a server

+ Useful for small organisations

Question 14

Peer-to-peer disadvantages

Answer 14

• No central server to protect security

- Data cannot be retrieved from a computer that is switched off

Question 15

Client side processing

Answer 15

Scripts that handle initial processing are run on the terminal rather than the main server

Question 16

Client-side uses

Answer 16

Tasks such as validating inputs which could be run quicker without being passed to a server

Question 17

Client side advantages

Answer 17

+ Quicker execution as there is no communication with the server
+ Removes potentially unnecessary processing from the server

Question 18

Client side disadvantages

Answer 18

• Not all browsers support all scripts

- Dependent on the machine’s performance

Question 19

Application Programming Interface(API)

Answer 19

A set of tools that can be used for building software applications

Question 20

Server

Answer 20

A device which provides a central point of control

Holds information and resources and has greater processing power

Question 21

Search engine

Answer 21

A program that searches through a database of internet addresses based on criteria set by the client