![]() ![]() How many hosts can each of these subnetworks accommodate? Well, there are now 8 bits left for host addressing. If we have 172.16.0.0/16 and we decide to borrow 8 bits for subnetting, we can create 2^8 or 256 different subnetworks. It is 2^n where n is the number of bits we borrow from the host bits. ![]() The formula for how many networks we can create is very similar. The formula for how many hosts you can have always remains the same it is 2^h-2. As we “borrow” bits for subnetting from the host bits, we can create more subnets, but we do so at the cost of being able to support fewer and fewer host systems per network. When we subnetwork, we play a balancing act. So if we want to use the 172.16.0.0 private address space, we need to “subnetwork” this address space in order create more network addresses that can each accommodate an appropriate number of host systems. That’s great, that’s amazing, and.it also turns out that this is impossible! In a typical TCP/IP network of today, you are going to have big problems if you start placing 500 or more systems in the same network (subnet), never mind 65,000 or more! Number of Subnets and Number of Hosts We need a calculator for this one because the number is so big! It turns out that 65,534 can live in this network. So the formula is 2^h-2 where h is the number of host bits. You take the number of bits used for host addressing (16), and you raise 2 to this power and then subtract 2. When you look at a Class B private address like 172.16.0.0/16 (255.255.0.0), you can calculate the number of hosts that can live in this network. Breaking the network up allows the network to be more efficient and more secure and more easily managed. Why do we even need this concept of subnetting? Well, we need to break up our networks into smaller networks all of the time. Also, this article assumes you can manually convert a binary octet to decimal, and vice versa. This article assumes you have a basic working knowledge of IP addressing and subnet masks. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |