1. Introduction to Networking (Yarnfield) Classful subnetting

2. Objective  To cover the subnetting process  Be able to subnet from a variety of information

3. Subnetting  The process of dividing a network up into subnets and to assign each subnet a valid network IP address, and the hosts on that subnet valid IP addresses Subnet 1 Subnet 3 Subnet 2

4. We need to find out  How many subnets does the subnet mask provide?  How many valid hosts per subnet are available?  What are the valid subnets?  What is the broadcast address of each subnet?  What are the valid hosts in each subnet?

5. We need  An IP address to subnet And  The number of subnets we wish to make Or  The subnet mask Or  The number of borrowed bits

6. Example 192.5.5.35 255.255.255.224

7. Example  IP address: 192.5.5.35  Subnet mask: 255.255.255.224  Work out 1. Network ID Class 2. Major network address 3. Major broadcast address 4. First host of the major network 5. Last host of the major network Class C 192.5.5.0 192.5.5.255 192.5.5.1 192.5.5.254

8. Example  IP address: 192.5.5.35  Subnet mask: 255.255.255.224  Now we need to work out the subnet information 1. Number of subnet bits 2. Number of host bits 3. Subnet address for the given host IP address 4. Range of host addresses for this subnet 5. Broadcast address for this subnet 3 subnet bits 5 host bits 192.5.5.32 192.5.5.33 – 192.5.5.62 192.5.5.63

9. Example  IP address: 192.5.5.35  Subnet mask: 255.255.255.224  Now we need to find other subnet information 1. Total number of useable subnets 2. Number of valid host IP addresses per subnet 3. Convert given subnet mask to binary 4. Convert given host IP address to binary 5. Subnetwork address with slash (/) mask for the assigned subnet 6 30 11111111.11111111.11111111.11100000 11000000.00000101.00000101.00100011 192.5.5.32 / 27

10. Exercise  IP address 202.168.2.40  Subnet mask 255.255.255.240  Find out: 1. Network ID Class 2. Major network address 3. Major broadcast address 4. First host of the major network 5. Last host of the major network 6. Number of subnet bits 7. Number of host bits 8. Subnet address for the given host IP address 4. Range of host addresses for this subnet 5. Broadcast address for this subnet 1. Total number of useable subnets 2. Number of valid host IP addresses per subnet 3. Convert given subnet mask to binary 4. Convert given host IP address to binary 5. Subnetwork address with slash (/) mask for the assigned subnet

11. Questions... ... are there any?