IPv4 Addresses and Subnets

What is subnet mask 255.255.128.0 in CIDR notation?

/17

What are the possible values of a bit?

0 and 1

Express 10.5.21.12/12 in binary format for the IP address and subnet mask.

00001010.00000101.00010101.00001100 11111111.11110000.00000000.00000000

How many bits are each octet made up of?

8 bits

Is the IP address 125.16.0.5 a valid IP address? Why?

Valid. Octal values may range from 0 to 255. However, an IP address may not start with a 0.

What is the decimal value of the binary 10101010?

170

Write the subnet mask for /12

255.240.0.0

Write the subnet mask for CIDR /18.

255.255.192.0

Every device on a network has a unique ______ and _______.

IP address MAC addresss

How does allocating subnets reduce the number of hosts are available?

Because each subnet requries a broadcast address and a network address

To which IP class does the IP 192.12.13.14 belong?

Class C

A _____ is any end user device such as a computer, printer, laptop, or tablet that connects to the network.

host

A network can be divided into smaller networks called ________

subnets

In IP address 192.168.5.23/29, how many subnets and hosts are created?

subnets = 2^5=32 and hosts are 2^3=8. So there are 32 subnets each containing 8 host IP addresses.

What can subnets be used for?

1. Provide individual organizational units (i.e. teams or departments) 2. Simplify network 3. Make departmental data private

The bits set with a 1 are the _____ portion of the subnet mask and the bits set to 0 are the ______ portion of the mask

1. network address 2. host

Write the subnet mask for CIDR /21.

255.255.248.0

What is a private IP address?

Classes A, B, and C each have a range of IP addresses reserved for internal use, which means that they cannot be used on the public Internet.

What is the IP address 11000000.00101010.00000111.00001111 in decimal format?

192.42.7.15

Express the decimal value 127 in binary format.

01111111

Express the IP address 127.124.16.1 in binary format.

01111111.01111100.00010000.00000001

The mask divides an IP address into an extended ________ and a ___________.

1. network address 2. Host address

Express 192.168.24.12/27 in binary format for the IP address and subnet mask.

11000000.10101000.00011000.00001100 11111111.11111111.11111111.11100000

Express the decimal value 252 in binary format.

11111100

What is the CIDR notation of 192.168.5.12 255.255.255.128?

192.168.5.12/25

If needed, allocate the network on IP 202.8.21.12 to have at least 12 hosts per subnet. What would be the CIDR notation?

202.8.21.12/28

What are the 2 ip addresses that are in use by default for 207.21.54.0/24?

207.21.54.0 network address 207.21.54.0 broadcast address

What is the decimal value of the binary 00011110?

30

How many bits are always in an IPv4 address?

32 bits (8 bits times 4 = 32 bits).

How many Octets does an IPv4 address have?

4

How many bytes are always in an IPv4 address?

4

How many bytes does a subnet mask have?

4 bytes (same as IP address) ex: 255.0.0.0

In IP address 192.168.5.23/29, how many bits are allocated for subnets and hosts?

5 bits are allocated for subnets and 3 for hosts.

How many classes of IP addresses are there? WHat are they for?

5 classes A - public B - public C - public D - multicast E - research and development

You need to allocate the network on IP 205.225.16.84 to have at least 60 hosts per subnet. Write the CIDR notation. Then, write the network, broadcast and last Host IP address for each subnet

Allocate 4 subnets each containing 64 host IP addresses. 205.225.16.84/26. Subnet 1: NW=205.225.16.0, BC=205.225.16.63, LH=205.225.16.62. Subnet 2: NW=205.225.16.64, BC=205.225.16.127, LH=205.225.16.126. Subnet 3: NW=205.225.16.128, BC=205.225.16.191, LH=205.225.16.190. Subnet 4: NW=205.225.16.192, BC=205.225.16.255, LH=205.225.16.254

How many available subnet addresses and host addresses are available on the network address 207.21.54.0/24? What is the range of host addresses in that subnet?

Available addresses in subnet: 2^8 (256) addresses are available in the subnet Available host addresses in subnet: 256 - 2 (network address & broadcast address) = 254 host addresses available. Range: 207.21.54.1 to 207.21.54.254

What notation does IPv4 addresses use?

Dotted decimal notation

What is CIDR notation?

CIDR stands for Classless Inter-Domain Routing, and is a way of specifying the subnet mask for an IP address. It simplefies the notation for the subnet mask. EX: 192.168.5.12/25

To which IP class does the IP 10.27.13.25 belong?

Class A

To which IP class does the IP 141.68.27.102 belong?

Class B

T/F subnet masks can not bre written in the same format as an IP address

F

What is an IPv4 address?

It is a core protocol used for Internet communication that was introduced in 1983.

What 2 ways are used to translate a private ip address to a public ip address?

Network Address Translation (NAT) Port Address Translation (PAT)

Does a CIDR mask of /31 or /32 make sense? Why or why not?

No because /31 allocates 1 bit for hosts which is only 2^1=2 hosts and both IPs would be used for the network and broadcast addresses. /32 allocates 0 bits for hosts so it's useless.

Can IP address 10.27.14.8 travel over the public Internet? Why?

No, it is a Class A private IP address.

Can IP address 192.168.1.27 travel over the public Internet? Why?

No, it is a Class C private IP address.

Is the IP address 152.62.256.1 a valid IP address? Why?

Not valid. No octet may exceed 255.

What is the basic process to translate private IP addresses to public IP addresses?

Outgoing data from your device is sent through a router, which maps your device's private IP address to a public IP address. When the data returns to that router, it looks up your device's private IP address and routes it to its destination.

In the last Class C subnetting example shown with IP 192.168.2.7/27, what are the network, broadcast, and last Host IP address for subnets 3,4,5, 6 and 7?

Subnet 3: NW=192.168.2.64, BC=192.168.2.95, LH=192.168.2.94. Subnet 4: NW=192.168.2.96, BC=192.168.2.127, LH=192.168.2.126. Subnet 5: NW=192.168.2.128, BC=192.168.2.159, LH=192.168.2.158. Subnet 6: NW=192.168.2.160, BC=192.168.2.191, LH=192.168.2.190. Subnet 7: NW=192.168.2.192, BC=192.168.2.223, LH=192.168.2.222.

What does a subnerrt do?

The subnet provides a specific range of IP addresses for a group of hosts use.