1. Subnetting

2. Binary to Decimal Conversion Decimal to Binary Conversion Classes of IP Addresses Subnet Masks 7 step method to practical subnetting – Class C – Class B

3. Binary to Decimal Conversion

4. Place Card Method 1286432168421 2727 2626 2525 2424 23232 2121 2020

5. Binary to Decimal Conversion Place Card Method for 1100 0000 1286432168421 2727 2626 2525 2424 23232 2121 2020 11000000 192 = 128 + 64 + 0 + 0 + 0 + 0 + 0 + 0

6. Binary to Decimal Conversion Place Card Method for 1111 0000 1286432168421 2727 2626 2525 2424 23232 2121 2020 11110000 240 = 128 + 64 + 32 + 16 + 0 + 0 + 0 + 0

7. Decimal to Binary Conversion Place Card Method for 129 1286432168421 2727 2626 2525 2424 23232 2121 2020 129 = 128 + 0 + 0 + 0 + 0 + 0 + 0 + 1

8. Decimal to Binary Conversion Place Card Method for 129 1286432168421 2727 2626 2525 2424 23232 2121 2020 10000001 129 = 128 + 0 + 0 + 0 + 0 + 0 + 0 + 1

9. Decimal to Binary Conversion Place Card Method for 255 1286432168421 2727 2626 2525 2424 23232 2121 2020 11111111 129 = 128 + 64 + 32 +16 + 8 + 4 + 2 + 1

10. IP Address Example of an IP address is 148.8.20.10 (4 octets) Each octet is an 8 bit binary number Therefore, an IP address is 32 bits. 14882010 10010100000010000001010000001010

11. IP Address Each IP address is broken up into a Network Address and a Host address 14882010 10010100000010000001010000001010

12. IP Address Classes ClassNetwork AddressHost Address A1 st OctetLast three Octets B1 st Two OctetsLast Two Octets C1 st Three OctetsLast Octet

13. IP Address Classes A. B. C. D Class1 st OctetNumber of Networks Number of Hosts A1-1261262 24 = 16,777,216 B128-19116,3842 16 = 65,536 C192-2232,097,1522 8 = 256

14. Subnet Masks Tells the device which bits are host address and network address. ClassSubnet Mask Binary A 255.0.0.0 11111111.00000000.00000000.00000000 B 255.255.0.0 11111111. 11111111. 00000000.00000000 C 255.255.255.0 11111111. 11111111. 1111111.00000000

15. Subnetting What is subnetting – Process of subdividing a single class of network into multiple subnetworks. – A subnetted network address contains a network address, subnet address and host address.

16. Subnetting ClassSubnet Mask Binary A 255.0.0.0 11111111.00000000.00000000.00000000 B 255.255.0.0 11111111. 11111111. 00000000.00000000 C 255.255.255.0 11111111. 11111111. 1111111.00000000

17. Subnetting Why subnet – Reduce Collision Domain – Makes it easier to manage your network (lower TCO) – Makes you network more secure

18. Class C Subnet Example – Assigned 200.10.20.0

19. 1.) Determine # of subnets

20. 2.) Determine # of bits you can borrow 200 1100 1000 10 0000 1010 20 0001 0100 0 hhhh 148 1001 0100 8 0000 1000 0 hhhh 0 hhhh 11 0000 1011 0 hhhh 0 hhhh 0 hhhh For a class C address we have 8 host address bits to work with. You need to borrow at least 2 bits for the subnet address and you must leave at least 2 host bits for the host address. Therefore, we can borrow 2 to 6 bits on a class C address.

21. 3.) Determine # of bits you need to borrow 2^n -2 = number of useable subnets Borrowed BitsUseable Subnets Useable Host Addresses

22. 4.) High Order Bits Set the high order bits (determined above) to 1.

23. 5.) Subnet Mask Combine the Default Subnet Mask with value determined in step #4.

24. 6.) Determine the IP range of each subnet. 11100000 Sub Host 5 host address bits or 2^5 hosts per subnet

25. 7.) Determine Range of IP Addresses in each subnet We’ve determined that there are 32 hosts per subnet. 200.10.20.0200.10.20.

26. 7.) Determine Range of IP Addresses in each subnet We’ve determined that there are 32 hosts per subnet. 200.10.20.0200.10.20.31 200.10.20.32200.10.20.63 200.10.20.64200.10.20.95 200.10.20.96200.10.20.127 200.10.20.128200.10.20.159 200.10.20.160200.10.20.191 200.10.20.192200.10.20.223 200.10.20.224200.10.20.255

27. Useable IP addresses We discard the 1 st and last subnet Discard the 1 st and last IP address in each subnet. Our 1 st useable IP address in the first useable subnet that can be assigned to a node on our network would be: – 200.10.20.33