Posted Thu, 01 Jan 2015 06:00:00 GMT by Portal Admin

What does the "/24" mean? How does that relate to my subnet mask?

InterMapper uses the Classless Inter-Domain Routing (CIDR) notation to represent IP subnet information. The number in the "/xx" shorthand stands for the number of bits set to one in the subnet mask. The convention is always to start at the left end of the 32-bit subnet mask. The table below shows the correspondence between the "/xx" notation and the actual numeric representation.

Code:
    Subnet Mask    # of Addresses              Subnet Mask      # of Addresses
/1  128.0.0.0    2.1 billion          /17  255.255.128.0    32,766
/2  192.0.0.0    1 billion            /18  255.255.192.0    16,382
/3  224.0.0.0    536 million          /19  255.255.224.0    8,190
/4  240.0.0.0    268 million          /20  255.255.240.0    4,094
/5  248.0.0.0    134 million          /21  255.255.248.0    2,046
/6  252.0.0.0    67 million           /22  255.255.252.0    1,022
/7  254.0.0.0    34 million           /23  255.255.254.0    510
/8  255.0.0.0    17 million (Class A) /24  255.255.255.0    254 (Class C)
/9  255.128.0.0  8.4 million          /25  255.255.255.128  126
/10 255.192.0.0  4.2 million          /26  255.255.255.192  62
/11 255.224.0.0  2.1 million          /27  255.255.255.224  30
/12 255.240.0.0  1 million            /28  255.255.255.240  14
/13 255.248.0.0  524 thousand         /29  255.255.255.248  6
/14 255.252.0.0  262 thousand         /30  255.255.255.252  2
/15 255.254.0.0  131 thousand         /31  255.255.255.254  RFC 3021
/16 255.255.0.0  65,534 (Class B)     /32  255.255.255.255  A single address

You must be signed in to post in this forum.