2.06 - The Internet Infrastructure

Question 1

What is the Internet?

Answer 1

The internet is the biggest internetwork in exsistence and has evolved to its current form and is still evolving towards its future form. There is no agreed definition of the Internet’s structure, but there is a hierarchical aspect to it.

Question 2

What was the initial function of the ISP?

Answer 2

The initial function of an ISP was to give Internet access to an individual or company, and now it is performed by an access ISP

Question 3

What performs the initial function of the ISP?

Answer 3

Access ISP

Question 4

Name

An example of the hierarchy aspect of the Internet

Related to ISPs

Answer 4

Access ISPs connect to middle-tier or regional ISPs, which are connected to tier 1 or backbone ISPs.

Question 5

What are ISPs?

Answer 5

ISPs are networks. The initial function of an ISP was to give Internet access to an individual or company, and now it is performed by an access ISP.

Question 6

What are nodes?

Answer 6

The Internet is consist of a set of fibre-optic cables laid under the sea and across the land, which can be described as a mesh structure. The mesh of cables contains many points where the cables connect together, which we call nodes

Question 7

Where are the Routers found in the Internet?

Answer 7

At each node

Question 8

What are routers?

Answer 8

At each node there is a device called the router. It is conncted to several other routers and its function is to choose the best route for transmission

Question 9

Name

Another name for 1st tier ISP

Answer 9

Backbone ISP

Question 10

Name

Another name for middle tier ISP

Answer 10

Regional ISP

Question 11

What is the type of topology the Internet is conncted in?

Answer 11

Mesh topology

Question 12

Where else other than nodes are routers found?

Answer 12

Within the ISP networks

Question 13

Name

PSTN full form

Answer 13

Public Switched Telephone Network

Question 14

Name

POTS full form

Answer 14

Public Old Telephone Service

Question 15

What is the formal name of POTS

Answer 15

PSTN

Question 16

What is PSTN?

Answer 16

PSTN is a communication system that was not originally designed for computer networking but now provides significant infrastructure support for the internet

Question 17

In the past, What type of signals did telephone networks carry?

Answer 17

It carried analog signals, however digital signals could be used if there were a modem at each end to convert digital signals to analog.

Question 18

What are modems?

Answer 18

Modems convert digital signals to analog signals that are then sent down a telephone line. Another modem might be there to reverse the process accordingly

Question 19

Why did companies paid for leased line service?

In the past

Answer 19

Companies would be provided with a dedicated and permenant connection link with garanteed transmission speed

Question 20

What did companies use to establish WANs and MANs?

In the past

Answer 20

Leased line service

Question 21

How did PSTN upgrade their main communication lines?

Answer 21

Switched it to Fibre optic

Question 22

How did upgrading the main communication lines of PSTN benefit it?

Answer 22

It allowed improved leased line services to ISPs and allowed them to provide their own ISP services.

Question 23

What are the 2 types of services provided by the mordern PSTN?

Answer 23

1. Broadband network connection
2. WiFi Hostpot technology

Question 24

How are cell phones provided with an Internet connection?

Answer 24

Mobile phone companies act as ISPs. The phone is equipped with a software that communicates with standard cell tower, to access wireless telephone network, providing connection to the internet