Quiz 2

Question 1

Which of the following protocols belong to the application layer of the TCP/IP protocol stack?

a) TCP

b) DNS

c) UDP

d) HTTP

e) IP

Answer 1

b) DNS
d) HTTP

Question 2

What service does the TCP/IP network layer provide

a) Unreliable multi-hop communication of datagrams between
endpoints

b) Reliable point-to-point transmission of datagrams

c) Reliable bidirectional transmission of a stream of bytes

Answer 2

a) Unreliable multi-hop communication of datagrams between endpoints

The network layer, specifically the Internet Protocol (IP), provides basic packet delivery services. It forwards datagrams from the source to the destination across multiple hops (routers). However, it does not guarantee delivery, order, or protection against duplication. Hence, the communication is considered “unreliable.”

Question 3

Assume that a router is connecting to three different communication links. How many instances of the link layer would the router have

a) 6

b) 1

c) 3

Answer 3

c) 3

Question 4

What is the IP address 10011110001110010100011001111010 (32-bit) written in dotted-decimal notation

a) 158.57.70.122

b) 127.56.1.7

c) 236.17.90.2

Answer 4

a) 158.57.70.122

Question 5

What 48-bit pattern does the link-layer address 50:7B:9D:E7:19:D0 correspond to

a) 010111100111101101011101111001111101100111010000

b) 010101000111101110001101101001110000100101010000

c) 010100000111101110011101111001110001100111010000

Answer 5

c) 010100000111101110011101111001110001100111010000

50: 01010000
7B: 01111011
9D: 10011101
E7: 11100111
19: 00011001
D0: 11010000

Question 6

How are communication end-points identified at the transport layer of the TCP/IP protocol stack

a) Using IP addresses and link-layer addresses

b) Using IP addresses and port numbers

c) Using only IP addresses

d) Using IP addresses and process identifiers

Answer 6

b) Using IP addresses and port numbers

Question 7

What is the main purpose of the Socket API provided via the operating system

a) Makes it possible to access the Domain Name Systems from
within applications

b) Makes it possible for application developers to access the
TCP and UDP transport services

c) Makes it possible to implement shared memory
communication between processes on the same machine

Answer 7

b) Makes it possible for application developers to access the
TCP and UDP transport services

Question 8

What service does the UDP protocol provide

a) Reliable transmission of datagrams of a single
communication link

b) Unreliable end-to-end transmission of datagrams between
hosts

c) Reliable bidirectional transmission of datagrams between
hosts

Answer 8

b) Unreliable end-to-end transmission of datagrams between
hosts

Question 9

What service does the TCP protocol provide

a) Unreliable transmission of a sequence of bytes between
hosts

b) Reliable bidirectional transmission of byte-streams between
hosts

c) Reliable transmission of datagrams on a single
communication link

Answer 9

b) Reliable bidirectional transmission of byte-streams between
hosts

TCP (Think Chat Protocol): Reliable, ordered, and controlled conversation between two devices.

Question 10

All running processes constituting a networked and distributed application must be implemented in the same programming language

a) True

b) False

Answer 10

b) False

Question 11

Which of the following method/operations does the HTTP protocol support

a) POST

b) DELETE

c) GET

d) PUT

Answer 11

a) POST

b) DELETE

c) GET

d) PUT

Question 12

What is a main purpose of the Domain Name System (DNS)

a) Mapping of IP addresses to link-layer addresses

b) Mapping of hostnames to IP addresses

c) Mapping of Universal Resource Identifiers to HTML webpages

Answer 12

b) Mapping of hostnames to IP addresses