Network & Web Technologies ii - Protocols & Standards

Question 1

HTTP (Hypertext Transfer Protocol)

Answer 1

Application Layer
Facilitates clients requesting information from the servers.
Each HTTP request by a client expects a HTTP response from the server.

Question 2

Get and Post requests

Answer 2

The two main types of HTTP request.
‘Get’ is harmless, repeatable and can be bookmarked.
‘Post’ is for when change is meant to occur (e.g. create/update/ destroy operations).

Question 3

URL (Uniform Resource Locator)

Answer 3

Text string representing a destination for a protocol (e.g. HTTP) request.
Several parts to URLs; protocol, host, port, path and query.

Question 4

API (Application Programmers Interface)

Answer 4

Series of functions or protocol endpoints allowing apps to access features of another system.
E.g. web APIs that use HTTP/ API libraries that provide custom functions.

Question 5

Server Side Processing

Answer 5

Server generating on demand content (e.g. personalised HTML) to send to clients.

Question 6

Web API

Answer 6

Modern approach to server side processing.

Sends unformatted data to the client on demand and the client decides how to render it.

Question 7

Client Side processing

Answer 7

Client generating content based on a data requested from the server.

Question 8

Javascript

Answer 8

Created to make web pages interactive.
Can execute HTTP requests without page reload; allowing dynamic web apps to be created (e.g. Google Docs) where the JS interacts with the web APIs.

Question 9

LAN (Local Area Networking)

Answer 9

Geographically small area e.g. buildings or several buildings on the same site.

Question 10

WAN (Wide Area Networking)

Answer 10

Geographically remote area e.g. across a country, between continents.
Connects LANs together.

Question 11

Explain Bus Topology

Answer 11

All devices are connected to a central (backbone) cable.
All devices have equal rights via the backbone cable.
If 2(+) devices send data via the backbone a collision occurs
Random timer + request withdrawn in collision in order to resend the request.

Question 12

Bus Topology (+ve & -ve)

Answer 12

+ve: Easy setup & maintenance
Cheap installation
For small networks

-ve: More devices = Less efficient
Heavily dependent on central cable
Low security - all devices can see the data
Hard to isolate faults
Collisions occur

Question 13

Explain Ring topology

Answer 13

Singular direction data transfer direction using control signal called ‘token’.
Only the node with the ‘token’ can transmit data, avoiding collisions.
Message examined by each successive computer. (to check if they are the message’s destination.
When the message is received, the token is put back on the network for the next node that requires its use.

Question 14

Ring Topology (+ve & -ve)

Answer 14

+ve: unidirectional data transmission.
Easily modular for devices.
Cheaper than star network

-ve: Less secure; data transmitted between 2 devices pass through all intermediate devices.
More devices = slower data transmission
1 node failure = whole network fail.