aaronjwilkinson Posted February 12, 2014 Share Posted February 12, 2014 i've working in IT for a fair while, but the logic behind subnetting is something i've always struggled with (and mental arithmetic in general)I've decided to pull my finger out with this and try to get the process hard-wired in my brain due to an exam i'm studying to pass.Anyway, could someone in the know take a look at the workings in the following link and see if you agree it's accuracy?Cheers http://imageshack.com/a/img822/6992/qfv5.jpg Link to comment Share on other sites More sharing options...
+BudMan MVC Posted February 12, 2014 MVC Share Posted February 12, 2014 here you go, looks like your good to go matches up. Subnet Network Address Starting Host End Host Broadcast Netmask 0 192.168.0.0 192.168.0.1 192.168.0.30 192.168.0.31 255.255.255.224 1 192.168.0.32 192.168.0.33 192.168.0.62 192.168.0.63 255.255.255.224 2 192.168.0.64 192.168.0.65 192.168.0.94 192.168.0.95 255.255.255.224 3 192.168.0.96 192.168.0.97 192.168.0.126 192.168.0.127 255.255.255.224 4 192.168.0.128 192.168.0.129 192.168.0.158 192.168.0.159 255.255.255.224 5 192.168.0.160 192.168.0.161 192.168.0.190 192.168.0.191 255.255.255.224 6 192.168.0.192 192.168.0.193 192.168.0.222 192.168.0.223 255.255.255.224 7 192.168.0.224 192.168.0.225 192.168.0.254 192.168.0.255 255.255.255.224 Link to comment Share on other sites More sharing options...
aaronjwilkinson Posted February 12, 2014 Author Share Posted February 12, 2014 Yey, the only mistake i look to have made is calling network 0 network 1 I keep forgetting that zero is a REAL number in subnetting haha Cheers :) Link to comment Share on other sites More sharing options...
Descartes Posted February 12, 2014 Share Posted February 12, 2014 I keep wondering why the IP team chose a decimal notation over hexadecimal or binary to begin with. At least that's fixed in IPv6 :P Link to comment Share on other sites More sharing options...
+John Teacake MVC Posted February 12, 2014 MVC Share Posted February 12, 2014 Depends if you are using Cisco (Or other vendors, See appropriate documentation). You can set the ip subnet zero I think. Link to comment Share on other sites More sharing options...
sc302 Veteran Posted February 12, 2014 Veteran Share Posted February 12, 2014 Ok, so lets do this logically 32 bit mask is 255.255.255.255 which allows for 1 address per network 31 bit mask is 255.255.255.254 which allows for 2 addresses per network 30 bit mask is 255.255.255.252 which allows for 4 addresses per network 29 bit mask is 255.255.255.248 which allows for 8 addresses per network 28 bit mask is 255.255.255.240 which allows for 16 addresses per network 27 bit mask is 255.255.255.224 which allows for 32 addresses per network 26 bit mask is 255.255.255.192 which allows for 64 addresses per network You want to divide 6 into 255 which gives you roughly 42. You can go anywhere up to 42 address per network and have your 6 required networks. If you notice everything is doubling on the network address side...1*2=2, 2*2=4, 4*2=8 on the bit mask side 255-1=254, 254-2=252, 252-4=248, 248-8=240 (see the pattern? the -x is doubling as well). Basically, the doc you have is correct. Link to comment Share on other sites More sharing options...
riahc3 Posted February 13, 2014 Share Posted February 13, 2014 Hello, Woah! Handwriting! Havent seen that in a while! Very nice handwriting BTW. Anyways, here is a good thread also that makes sense to me at least: http://www.techexams.net/forums/ccna-ccent/38772-subnetting-made-easy.html Link to comment Share on other sites More sharing options...
Recommended Posts