Very nice Kenn!! Ok so if I had 192.168.1.0/25 the range would be 192.168.1.0 - 192.168.1.127 /26 would be 192.168.1.0 - 192.168.1.192 ? or is it 192.168.1.0 - 192.168.1.64 ? Is that correct? Not sure how to make a net mask out of 192.168.1.0/25 - would it be 255.255.255.128? Thanks!! On 2015-08-31 02:55, parabellum7@yahoo.com wrote: > Hi Keith, > > If I recall correctly, the /24 part of 192.168.0.0/24 is the subnet > specified in CIDR notation (Classless Inter Domain Routing). > > Think in binary terms, that /24 equals > 11111111.11111111.11111111.00000000 (note there's 24 1's) equals > 255.255.255.0 so is a class C subnet with the first three octets being > the network mask. > > Likewise if you had an IP addy followed by a /8 that equals > 11111111.00000000.00000000.00000000 equals 255.0.0.0 so is a class A > subnet. > > Called octets cuz there's 8 bits hence a decimal max of 255. > > CIDR is usually seen at ISP's or in enterprise networks that need to > subnet further as the network mask does not have to align with the > octet boundary as it does in the classfull network addressing we're > used to. That's where things get weird and all this because those > silly routers only speak binary. :] > > If you're seeing 192.168.0.0/24 in a zenmap target field it means scan > everything from and including 192.168.0.0 to 192.168.0.255. > > > IP network classes or Classfull Network Addressing > > - Range - - mask - # of networks # of nodes CIDR mask > A 1.1.1.1 - 126.255.255.255 255.0.0.0 126 16,777,214 /8 > B 128.0.0.1 - 191.255.255.255 255.255.0.0 16,384 65,534 /16 > C 192.0.0.1 - 223.255.255.255 255.255.255.0 2,097,151 254 /24 > D 224.0.0.1 - 239.255.255.255 > E 240.0.0.1 - 255.255.255.255 > > > > --Kenn > > --------------------------------------------------- > PLUG-discuss mailing list - PLUG-discuss@lists.phxlinux.org > To subscribe, unsubscribe, or to change your mail settings: > http://lists.phxlinux.org/mailman/listinfo/plug-discuss -- Keith Smith --------------------------------------------------- PLUG-discuss mailing list - PLUG-discuss@lists.phxlinux.org To subscribe, unsubscribe, or to change your mail settings: http://lists.phxlinux.org/mailman/listinfo/plug-discuss