Several screenshots of TCP/IP protocol and Their subnet division methods

TCP/IP protocol and subnet division method




I. questions to consider when dividing subnets: 1. number of subnets to be divided 2. number of hosts per subnet 2. to determine the subnet mask, follow these steps: 1. determine the number of subnets, convert them to the binary number, and determine the number of digits n. For example, if you need 6 subnets, the binary value of 6 is 110, a total of 3 digits, that is, n = 3; 2. Write the default subnet mask according to your IP address type. For example, in class C, the default subnet mask is 11111111.111111.1111.00000000. 3. Set the positions of the default subnet mask and the first n digits of the host number to 1, and the remaining positions to 0. If n = 3 and is a class C address, the subnet mask is 11111111.111111.11111111.11111111100000, And the decimal value is used to obtain invalid bandwidth. Because the network is divided into six subnets, it occupies the first three digits of the host number. If it is a class C address, the host number can only be expressed as five digits, therefore, the number of hosts in each subnet is (5 to the power of 2)-2 = 30. The role of the subnet mask is to allow us to parse the network number by bit and hour with the IP address, that is to say, the location corresponding to the network number should be 1 (including the location corresponding to the subnet number, of course ). Another problem is that we divide four subnets. The subnet masks of five subnets are the same as those of six subnets, because the binary values of four, five, and six are three, therefore, in the subnet mask, all three are set to 1, so there is no problem with the division. We can understand that the Division is 4, 5, and 6 subnetworks all occupy three of the host numbers.