If the range of IP 172.16.0.0/12 is class B , why can I use the subnet mask 255.255.255.0 in this range? - Quora
The Sky Networks - CIDR CIDR (Classless Inter-Domain Routing) notation rather than the common subnet mask 255.x.x.x when configuring addresses and networks. Refer to the CIDR Subnet Table to find the CIDR
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