Chapter 12: IP Addressing and Subnetting

Use the 2^s-2 formula and avoid the zero and broadcast subnets, if

classful routing protocol
RIP Version 1 or IGRP protocol
no ip subnet zero is configured

Use the 2^s formula and use the zero and broadcast subnets, if

classless routing protocol
RIP Version 2, EIGRP, or OSPF protocol
ip subnet zero command is configured or omitted (default)
VLSM is used
no other clues are provided

VLSM

Variable-Length Subnet Masking

SLSM

Static-Length Subnet Masking

NAT

Network Address Translation

Class A private reserved networks?

10.0.0.0

Class B private reserved networks?

172.16.0.0 to 172.31.0.0

Class C private reserved networks?

192.168.0.0 to 192.168.255.0

Length of an IPv6 address

128 bits

What is a bitwise operation

A bitwise operation is a Boolean operation carried out on a string of bits

Prefix notation is also known as ________

CIDR notation

resident subnet

The subnet in which a given IP address resides

subnet number

Like a network number, it's equal to the first possible address in a given subnet. Can be found by AND-ing an IP with its associated subnet mask. This will show what subnet the IP resides in.

given the subnet number (and probably subnet mask), how to find the subnet's directed broadcast address

change the values in the host part of the address to all 1's

The largest possible decimal value for an IP address octet

255 (256 values starting with 0)

The two reserved numbers in each subnet

the subnet number itself (lowest #, host portion all 0's)
AND
the directed broadcast address (highest #, host portion all 1's)

How to find the range of IP addresses in a subnet (how to find 1st and last addresses)

1st address: take the subnet number, add 1 to the 4th octet
last address: take the broadcast address, subtract 1 from the 4th octet