Addressing IP v4
W.Lilakiatsakun
Anatomy of IPv4 (1)
Dotted Decimal Address
Network Address
Host Address
Anatomy of IPv4 (2)
Octet
32 Bit Address
Binary to Decimal Conversion (1)
Binary to Decimal Conversion (2)
Decimal to Binary Conversion (1)
Decimal to Binary Conversion (2)
Decimal to Binary Conversion (3)
Type of IPv4 Address-Network Address
Type of IPv4 Address – Broadcast Address
Type of IPv4 Address – Host Address
Netmask (1)
• To identify the bit for the same position in the IP
address whether it is Network bit or Host bit
• If the value of Netmask is
– 1 is the Network bit
– 0 is the Host bit
• Example : IP address – 192.168.10.10 Netmask255.255.255.0
– Network bit = the most 24 significant bits
– Host bit = the least 8 significant bits
Netmask (2)
• Netmask can be represented as “prefix” (slash
format)
• The number of 1 is counted
– Netmask is 255.255.255.0 = /24
– 255 = 1111 1111 (8 bits)
• We can find Network Address (Network ID)
from IP Address
• Network Address = IP adresss & Netmask
Netmask (3)
• Logic AND (&)
–
–
–
–
0&0–0
0&1–0
1&0–0
1&1–1
As a result,
• X&0–0
• X&1–X
• Logic OR (|)
–
–
–
–
0&0–0
0&1–1
1&0–1
1&1–1
As a result,
• X|1–1
• X|0–X
Netmask (4)
• Example: IP address 192.168.10.20 /28
Network Address = IP address & Netmask
192.168.10.20 & 255.255.255.240
11000000 .10101000.00001010.00010100
11111111. 11111111.11111111.11110000
11000000 .10101000.00001010.00010000
• Question: IP address = 192.168.10.20 /22
• Network ID = ?
Netmask (5)
Network Address & Broadcast Address
Network ID = IP address that all host bits are 0s
– 192.168.10.20/24
– Network ID = 192.168.10.0
Broadcast ID = IP address that all host bits are 1s
– 192.168.10.20/24
– Broadcast ID = 192.168.10.255
Different Prefixes (1)
Different Prefixes (2)
Assigning Addresses
Calculating Addresses
Quiz
Basic Subnetting (1)
Basic Subnetting (2)
Basic Subnetting (3)
Basic Subnetting (4)
Basic Subnetting (5)
Basic Subnetting (6)
VLSM (Subnetting a subnet)
Problem
• This scenario has the following requirements:
– IP address : 192.168.15.0/24
– AtlantaHQ 58 host addresses
– PerthHQ 26 host addresses
– SydneyHQ 10 host addresses
– CorpusHQ 10 host addresses
– WAN links 2 host addresses (3 Links)
Answer