Networking

Subnet Mask:

 IP Address Range : 98.114.91.230/24 

 /24 is subnet mask. It tells that first 24 bits in the IP address indicate subnet address ( 98.114.91.0)  and remaining 8 bits indicate host address ( 0.0.0.230 ). Binary IP addresses with a host portion of all ones and all zeros are invalid. Hence 98.114.91.0 and 98.114.91.255 are not valid IP addresses ( first and last address on any subnet can not be assigned to a host ).
/24 can also be represented as 255.255.255.0

Network Classes

 Class A :  255.0.0.0 & first octet ( 0-127 )
Class B :  255.255.0.0 & first octet ( 128-191 )
Class C :  255.255.255.0 & first octet ( 192-223 )

Reference : https://support.microsoft.com/en-us/help/164015/understanding-tcp-ip-addressing-and-subnetting-basics

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