Lesson 1: Introduction, History, and Internet Architecture

Question 1

Who created the first experiment for the internet and how was it done?

Answer 1

J.C.R. Licklider led researchers Roberts to connect 2 computers, one in Massachusetts and one in California, via dial up telephone line

Question 2

What is the initial APRANET (1969)

Answer 2

Created by Roberts, it was a network of 4 computer nodes

Question 3

What is the Network Control Protocol (NCP) and why was it created?

Answer 3

The first APRANET host-to-host protocol was created to allow user application development (email)

Question 4

Who created TCP/IP, and for what functions?

Answer 4

Bob Kahn. New version of NCP that used open-architecture networking. IP for simple packet forwarding and addressing, TCP for flow control and lost packets recovery

Question 5

What is the DNS

Answer 5

Domain Name System, used to translate domain names into IP addresses

Question 6

What is the internet architecture?

Answer 6

layered protocol stack model, each layer dependent on service above and below it

Question 7

what is the OSI model?

Answer 7

7 layers: application, presentation, session, transport, network, data link, and physical

Question 8

What is the traditional Internet Architecture Model?

Answer 8

5 layers: application, transport, network, data link, and physical

Question 9

what are sockets?

Answer 9

the interface (how the layer is accessed) between the application and transport layer in the internet architecture model.

Question 10

name 4 protocols in the application layer.

Answer 10

HTTP, SMTP, FTP, DNS

Question 11

what is a packet of information called in the application layer

Answer 11

message

Question 12

What does the presentation layer do?

Answer 12

formats information and sends to application layer

Question 13

what is the session layer?

Answer 13

manages different transport streams within the same session between user applications

Question 14

what is the transport layer and what are its protocols?

Answer 14

responsible for end to end communication between end hosts. TCP and UDP.

Question 15

What is TCP?

Answer 15

transport control protocol, connection oriented service to application layer, manages message delivery to application, flow control, and congestion-control

Question 16

what is UDP?

Answer 16

user datagram protocol, connectionLESS, service to application layer without any reliability

Question 17

what is a packet of information called at the transport layer?

Answer 17

segment

Question 18

what is a packet of information called at the network layer?

Answer 18

datagram

Question 19

what is the network layer and its protocols?

Answer 19

moves datagrams between internet hosts. IP and routing

Question 20

what is the IP?

Answer 20

governs how data is sent and received across the internet, defines the hosts and routing

Question 21

what are packets of information called at the data link layer?

Answer 21

frames

Question 22

what are protocol examples at the data link layer?

Answer 22

Ethernet, WiFi, PPP

Question 23

what happens at the data link layer?

Answer 23

moves frame one node (host or router) to the next node. some guarantee of transmission delivery, but no reliability services like TCP

Question 24

what is encapsulation?

Answer 24

process of appending a header to a payload from the previous layer. used for layers and protocols to communicate information to each other.

Question 25

what is de-encapsulation?

Answer 25

the reverse process, where the header is stripped at each layer