ANDing - Linux Installation and Configuration Lecture Notes PDF

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Linux Installation and Configuration Lecture Notes...

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AND’ing The logic of ‘AND’ing can be explained by the following diagram. A

B TRUTH TABLE Switches SWITCH# 0 = open Light A B 1 = closed 0 0 0 = off 0 1 0 = off - + 1 0 0 = off 1 1 = ON

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Battery NOTICE THAT THERE IS ONLY ONE COMBINATION THAT ALLOWS THE LIGHT TO BE TURNED ON. THAT IS HOW logical ‘AND’ing is done. When we logically ‘AND’ the destination host IP address and the subnet mask, the result will give us the subnetwork (or network) address of the destination host. NOTE: I will only get a “1” result -if I “AND” a ‘1’ with another ‘1’ If either bit is 0 (zero) – I’ll get a 0 (zero) result. This is done vertically with the bit in the top binary number ‘AND’ed with the bit in the number below. Example: IP address 192. 168. 16. 33 Binary equivalent 11000000. 10101000. 00010000. 00100001 (Default ) subnet mask (255.255.255.0) 11111111. 11111111. 11111111. 00000000 result of ‘AND’ing 11000000. 10101000. 00010000. 00000000 (in dotted decimal form) 192. 168. 16. 0 This gives me the network ID for this host

Look at another example with 3 bits borrowed for subnetting. Example: IP address 192. 168. 16. 33 Binary 11000000. 1010100. 00010000. 00100001 Subnet mask (255.255.255.224) 11111111. 11111111. 11111111. 11100000 result of ‘AND’ing 11000000. 10101000. 00010000. 00100000 (in dotted decimal form) 192. 168. 16. 32 Notice that this gives us the sub-network number to which this host belongs in....