1. IP Addressing Dotted Decimal and Binary explanation

2. IP Addressing IP Addresses can be notated in Dotted Decimal and/or Binary, but you must understand both Dotted Decimal is what we are familiar with –eg. 128.41.230.65 –To find out what the value of the dotted decimal octet is we must know what the binary format is Binary bits are shown by a “1” or a “0” –“1” indicates that the binary place is “on” –“0” indicates that the binary place is “off”

3. IP Addressing IP addresses in dotted decimal contain 4 octets –Add up the number of “locations” contained by the dots : xxx.xxx.xxx.xxx = 4 octets –Each octet contains 8 binary bits that tell us what the value of the octet in the dotted decimal notation

4. Binary as it relates to the Octet XXX.XXX.XXX.XXX Each octet is made up of 8 binary bit “places” Calculate 4 octets X 8 bits = 32 bits total

5. Binary Place Values 00000000 1286432168421 = 0 00000001 = 1 00000011 = 3 = 255 01000011 = 67 10000000 = 128 ! Remember a binary bit is either on or off – “1” or “0” !

6. Converting Dotted Decimal to Binary 128.41.230.65 Lets convert the dotted decimal address shown here to binary

7. Converting Dotted Decimal to Binary Take the value of the first Octet 128 Binary would look something like this 10000000 ! Remember the value of the first binary bit place is 128 and the first bit place is “turned on” !

8. Converting Dotted Decimal to Binary Take the value of the second Octet 41 Binary would look something like this 00101001 ! Remember the values of the bit places turned on – 32, 8, and 1 – 32+8+1=41 !

9. Converting Dotted Decimal to Binary Take the value of the third Octet 230 Binary would look something like this 11100110 ! Remember the values of the bit places turned on – 128, 64, 32, 4, and 2 – 128+64+32+4+2=230 !

10. Converting Dotted Decimal to Binary Take the value of the forth Octet 65 Binary would look something like this 01000001 ! Remember the values of the bit places turned on – 64, and 1 – 64+1=65 !

11. Converting Dotted Decimal to Binary 128.41.230.65 The whole thing in binary would look like this 10000000.00101001.11100110.01000001

12. Now you Know how!!