I get the same results as Marko, but this may lay it out so you (and others) can see the development:
IP address = 32 bits Network portion = 22 bits Host portion = 10 bits Total addresses for host portion = 2^10 = 1024 Start with 192.168.24.0/22 Focus on the 3rd octet (network_host): 000110_00 400 hosts requires 9 bits (2^8 = 256, 2^9 = 512) and you will have some left in this block divide the /22 into two blocks of 512 addresses each: 0001100_0 (.24/23) and 0001111_0 (.26/23) use .24/23 for the 400-host network 200 hosts requires 8 bits (2^7 = 128, 2^8 = 256) and there will be some left in this block, too divide the .26/25 into 2 blocks of 256 addresses each: 00011110 (.26/24) and 00011111 (.27/24) use .26/24 for the 200-host network 50 hosts requires 6 bits (2^5 = 32, 2^6 = 64) and you will again have some leftovers divide the .27/24 into 4 blocks of 64 addresses each now looking at the 4th octet: 00_000000 (.0/26), 01_000000 (.64/26), 10_000000 (.128/26), and 11_000000 (.192/26) use the first two for the 50-host networks and the rest is easy My personal rule is to always start with the biggest blocks and work down from there. HTH Annlee Steven Aiello wrote: > I just started my routing class for my CCNP. We are covering CIDR. The > book is VEEEEEERY vague on how the bit patterns break down and are used. > > > This was a problem posed in one of my CCNP labs > > I have network number > > 192.168.24.0 / 22 > > from this I need > networks with > > 400 hosts > 200 hosts > 50 hosts > 50 hosts > 2 hosts (for serial int - no ip un-numbered allowed ) > 2 hosts > 2 hosts > > Also no NATing > > Thanks all I really could use the help > > Steve > **Please support GroupStudy by purchasing from the GroupStudy Store: > http://shop.groupstudy.com > FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html ________________________________________________________________________ This email has been scanned for all viruses by the MessageLabs Email Security System. For more information on a proactive email security service working around the clock, around the globe, visit http://www.messagelabs.com ________________________________________________________________________ Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=75172&t=75050 -------------------------------------------------- **Please support GroupStudy by purchasing from the GroupStudy Store: http://shop.groupstudy.com FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html