IP Addressing

Question 1

What do IP addresses provide?

Answer 1

A consistent method to identify a node/interface for every connection to the network.

Question 2

How long are IP addresses?

Answer 2

32 bits (4 decimal integers, each corresponding to one byte)

Question 3

Who is responsible for assigning address ranges?

Answer 3

ARIN - American Registry for Internet Numbers

Question 4

What portions are in an IP address?

Answer 4

Network portion (Network ID) and one that identifies the device on the network (Host ID)

Question 5

What are the leading edge bits and ranges for Class A, B, C, D, and E?

Answer 5

A: 0..   0.0.0.1-127.255.255.255
B: 10..   128.0.0.0-191.255.255.255
C: 110..   192.0.0.0-223.225.255.255
D: 1110...   224.0.0.0-239.255.255.255
E: 11110..   240.0.0.0-247.255.255.255

Question 6

Which class is reserved for future use and which for multicast?

Answer 6

Class D is multicast.

Class E is future use.

Question 7

How many tiers did the Internet originally have? What were they?

Answer 7

2: Internet, user networks

Question 8

How many tiers does the Internet have now? What are they?

Answer 8

3: Internet, subnet, user network

Question 9

What is a subnet?

Answer 9

Portion of the network distinguished by a subnet number that shares a network address with other portions of the network. Like a mini-internet to the nets below it.

Question 10

What is a subnet mask?

Answer 10

A number that identifies a subnetwork so an IP address can be shared on a LAN.

Question 11

What are two popular subnetting methods?

Answer 11

Fixed, complex

Question 12

T/F: to communicate, hosts must know either the physical address or the Internet address of each other.

Answer 12

False. They must know both.

Question 13

T/F: the relationship between the Ethernet address and IP address is an algorithm understood by ARP.

Answer 13

Not quite. There is no relationship. Address Resolution Protocol enables a host/router to obtain the correct Ethernet address when it sends a packet across the physical network with a known IP address.

Question 14

What is ARP?

Answer 14

Address resolution protocol

Question 15

T/F: Media Access address, Ethernet address, and physical address are all the same thing.

Answer 15

True, I think?

Question 16

What is ICMP?

Answer 16

Internet Control Message Protocol. Allows router or destination host to report an error in datagram processing to the source of the packet.

Question 17

T/F: ICMP and IP are mutually exclusive.

Answer 17

False. They need to be together forever!

Question 18

T/F: ICMP makes IP very reliable.

Answer 18

False. Higher-up applications must have better procedures to check stuff.

Question 19

What is the main purpose of ICMP?

Answer 19

To report errors. If it’s easy.

Question 20

Who provides supernetting addresses? What class are these?

Answer 20

ISPs provide C-class addresses for supernetting.

Question 21

T/F: ISPs can divide a C class address between customers.

Answer 21

False. They divide B-class Network IDs between customers.

Question 22

Fixed subnetting is used in what environment?

Answer 22

Class B. Portions of the host address is used for subnetting.

Question 23

What type of subnetting should be used for a sophisticated IP network architecture?

Answer 23

Complex

Question 24

Where is an ICMP message carried?

Answer 24

In an IP packet

Question 25

T/F: Checksum is applied on all fields of the ICMP packet.

Answer 25

True