IP Subents misunderstanding

themanofthehour · 01-31-2008, 06:38 AM

I dont understand this.

I need a minimum of 300 networks and with each network I want to allocate 50 host per network.

I have read books where its say I can use

255.255.255.128 = 11111111.11111111.11111111.10000000

That 1 in the end means 1 bit on. So 1 power of 2 is 2 correct?. This would give me 2 networks or 2 subnets.

In the book it says I can get 512 networks with 126 host each in network right?. I dont understand. Now I know where the 512 is coming from its coming from the left octet which is 9 1s including the next octect 1.Therefore I would get 512 networks.

However I dont understand, I thought you can only use bits which have 0 in them so I can use all those 1s in the 3 octet.

Please Help I dont understand!!!!

johnwill · 01-31-2008, 09:48 AM

Perhaps this will help: http://www.networkcomputing.com/unix...orial/001.html

Here's a subnet calculator: http://networking.ringofsaturn.com/IP/subnet.php

01-31-2008, 06:38 AM	#1 (permalink)
themanofthehour Registered User Join Date: Nov 2006 Posts: 20 OS: XP	IP Subents misunderstanding I dont understand this. I need a minimum of 300 networks and with each network I want to allocate 50 host per network. I have read books where its say I can use 255.255.255.128 = 11111111.11111111.11111111.10000000 That 1 in the end means 1 bit on. So 1 power of 2 is 2 correct?. This would give me 2 networks or 2 subnets. In the book it says I can get 512 networks with 126 host each in network right?. I dont understand. Now I know where the 512 is coming from its coming from the left octet which is 9 1s including the next octect 1.Therefore I would get 512 networks. However I dont understand, I thought you can only use bits which have 0 in them so I can use all those 1s in the 3 octet. Please Help I dont understand!!!!

01-31-2008, 09:48 AM	#2 (permalink)
johnwill Manager, Networking Forums Join Date: Sep 2002 Location: S.E. Pennsylvania, US Posts: 41,131 OS: Windows 7, XP-Pro, Vista, Linux Blog Entries: 1	Re: IP Subents misunderstanding Perhaps this will help: http://www.networkcomputing.com/unix...orial/001.html Here's a subnet calculator: http://networking.ringofsaturn.com/IP/subnet.php __________________ If TSF has helped you, Tell us about it! or Donate to help keep the site up! Microsoft MVP - Windows Desktop Experience