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...Subnetting it might be useful for the same administrative domain to contain several different networks link layer protocols without complex bridges subdomains smaller tables on routers but class b network addresses are running out so we can t waste them by assigning where they won densely populated and c only accommodate off machines which is too small even modest solution carve sub subnets of larger cont if all needed aware this would drastically increase size routing avoid problem outside a know about whole within however need their achieved having inside interpret ip address differently compatibility particular must operate exactly as before make decisions based number once configured little portion space that normally used identify host partitioned into subnet done in much way itself was unlike bits each not fixed instead determined mask part one has example parsed packet s prefix separate from length an contains every position including everywhere else also additional distinguish ...