RFC 2050: INTERNET REGISTRY IP ALLOCATION GUIDELIN...
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class


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... IP addresses need to be assigned/allocated in classless blocks. With this in mind, assignments will not be made in Class Cs or Bs but by prefix length. Consequently, an organization that would have been assigned a Class ...
... Class Cs or Bs but by prefix length. Consequently, an organization that would have been assigned a Class B in the past will now be assigned a /16 prefix, regardless of the actual address ...
... prefix, regardless of the actual address class. 4. All IP address ...



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