Easy way to remember IP Classes?

MPNX2

Does anyone have a trick for remembering what IP addresses are in what class? I have my test tomorrow afternoon and that is one thing I am stumbleing over. Also, there has been talk of DSL questions on the exam I see nothing about DSL in the technotes or in my Mike Meyers All In One book. Where could I get some quick info on that as well. Thanks for the help and the great site!

dcyphr80

I don't know any tricks but the main ones that I remember being on the test are only Class A, B, and C.

Class A 1-126 126.xxx.xxx.xxx

Loopback 127.xxx.xxx.xxx

Class B 128-191 191.124.xxx.xxx

Class C 192-223 223.149.16.xxx

The addresses to the right of the classes are examples.

Think of it this way. A is the first letter of the alphabet so it gets one network octet. B is the 2nd letter in the alphabet so it gets 2 octets, and C = 3 letter so it gets 3 octets. Hey I did just come up with a trick didnt I?? If you can remember the Maximum that each class can go then you should have no problem remembering the start point of each class because the start point is the next number after the previous Class Max, Except for the loopback just remember 127 and you should be fine. Then you know class B starts after that.

Max for A 126. Loopback 127. Max for B 191. Max for C 223. If you can remember the loopback is 127 you should have no problem. Because you alrdy know Class B starts after 127. And since you have memorized the Max of class B (191) then you alrdy know where class C starts (192). And if you memorize the Max of class C (223) then classes for the test will be a piece of cake.

I wish I could help ya on the DSL questions but I don't have the info for that.

viper75

No tricks, just go over the material over and over. It will sink in.

garv221

just know where "A" stops and "C" begins, then fill in the gaps.