[comp.protocols.tcp-ip] Allocating subnets

kurt@hi.unm.edu (Kurt Zeilenga) (06/28/88)

Just a note on allocating subnets (using a single netmask):

1) Pick an appropriate subnet mask (for then example: 255.255.255.0
   for a B).

2) Then allocate the subnets by changing the high order bits of the
   subnet field (ie: X.X.128 first, then 64, 192, 32, 96, ...)

3) Allocate hosts within a subnet using the low order bits of the
   host field (ie: 1, 2, 3).

Why?  Because what you think now might be the right subnet mask may
not be the right one in the future.  With this allocation scheme you
will have limited freedom to change the netmask later with minimal
hardship (renumbering).

	- Kurt