nigel6666

while we are on the subject of subnetting and trying to overload my brain i dont supose you have an easy way or example for vlsm the next section of the 125th subnet question wants to vlsm for 128 subnets my calcs ended up like this: so we start from 10.31.64.0 which is 00001010.00011111.01000000.00000000 so the original mask is 255.255.192.0 (/18) so we have used 10 bits for subnetting 00001010.00011111.01000000.00000000 so to futher subnet for 128 subnets i borrow a further 7 bits because 7 to power of 2 is 128 which is a mask of 255.255.255.128 (/26) so now i have 00001010.00011111.01000000.00000000 so i took the 00001010.00011111.01000000.00000000 turned all the borrowed bits on and end up with 64+32+16+8+4+2+1=127 so my first subnet is 10.31.64.0 (Subnet 0) 10.31.64.128 (subnet 1) 10.31.65.0 (subnet 2) and so on and i worked out my last subnet as being 10.31.127.128 (subnet 128) i think the math is correct. but i would like an easyer way to remember such as the way u explained earlyer not sure if u or anyone can help but it would be majorly appreciated!

Thanks for the reply, is there an easyer way to work out a specific subnet number? you seem to have done it alot easyer than i did! cheers

Hi just a quick question i'm studying for my CCNA and have been trying to wrap my head around subnetting, as part of my study i've been pulling questions from online and one of the questions was : identify the 125th subnet on a 10.0.0.0/18 (255.255.192.0) and for hours now i've been trying to work out a quick way to work out the 125th but have no idea of easy ways. i ended up doing: 10.0.0.0 is subnet 0 10.0.64.0 is subnet 1 10.0.128.0 is subnet 2 10.0.192.0 is subnet 3 10.1.0.0 is subnet 4 then i went "if subnet 4 is 10.1.0.0 then subnet 8 is 10.2.0.0 and so on" and worked my way to subnet 125. and my answer was 10.31.64.0 no idea if my answers are correct or not but can anyone point me in the right direction of an easy way to work out identifying specific subnet numbers?