IP Addressing Learn to Subnet In a single
IP Addressing Learn to Subnet In a single Slideshow
The Binary (This is not as hard as it looks) If we take our imaginary network of 208. 98. 1. 0 and convert it to binary: 11010000. 01100010. 00000001. 0000 Now we can sub-divide this network into smaller networks. We have 8 bits available in the ‘host’ portion of this network under the default netmask
This Is Easy (If you grasp the binary) We can divide these 8 bits whichever way best fits the number of networks and hosts per network that we require. If, for example we choose to split it down the middle, 4 and 4, we end up with 14 (2^4 = 16 – 2 = 14) networks and 14 hosts per network.
Breaking It Down (Enumerating the bits) So, we have 4 bits for the network portion, Let us enumerate all of the possible binary values using the 4 most significant bits of an 8 bit number: 0000 0100 1000 1100 0001 0101 1001 1101 0010 0110 1010 1110 0011 0111 1011 1111
Enumerating Subnets (What are the possible subnets) So, for each possible value for the 4 bits, we have a separate subnet: 208. 98. 1. 0 (0000) 208. 98. 1. 16 (0001 0000) 208. 98. 1. 32 (0010 0000) 208. 98. 1. 48 (0011 0000) … 208. 98. 1. 240 (1111 0000)
Enumerating Hosts (What are the usable IP addresses) In the subnet 208. 98. 1. 32 netmask 255. 240 we have 14 usable ips: 208. 98. 1. 33 (0010 0001) 208. 98. 1. 34 (0010) 208. 98. 1. 35 (0010 0011) … 208. 98. 1. 62 (0010 1110). 63 is the broadcast address (0010 1111)
Network Boundaries (Are you my neighbour? ) To calculate if two hosts are in the same network, you need to know their subnet mask. i. e. netmask 255. 240 208. 98. 1. 60 11010000. 01100010. 00000001. 00111100 208. 98. 1. 66 11010000. 01100010. 00000001. 01000010 So, we can see these two hosts are not in the same network
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