Also Talk About subnet division and subnet Communication

Also Talk About subnet division and subnet Communication 1. network IP address and subnet mask classification: Class A: IP: 0.0.0.0-127.255.255.255.255.255 subnet mask: 255.0.0.0 or labeled as/8 (8 1) Class B: IP: 128.0.0.0-191.255.255.255 subnet mask: 255.255.0.0 or/16 (16 1) Class C: IP: 192.0.0.0-1223.255.255.255.255 subnet mask: 255.255.255.0 or/24 (24 1) 2. determine available resources and requirements for the IP address resources or network number (Network Segment) owned by www.2cto.com a>, for example, 129.250.0.0/16. B> How many ip addresses need to be allocated? Example: 4000 pcc servers> How many subnets are needed? For example, five subnets are required. 3. subnet mask conversion. a> bitwise conversion (2n indicates the Npower of 2, and n indicates the bits). This algorithm requires several subnets !!! 2n-2> = number of subnets to be divided. Example: 2n-2 = 5 result n = 3 so we need to use 3 as the subnet mask. The original subnet mask is 255.255.0.0 = 11111111.111111.20.2.16.00000000. The subnet mask is: 255.255.224.0 = 255.determined subnet mask: 255.255.255.224.0 subnet ip range determined: 255-224 = 31 so: Subnet A used: 129.250.0.1-125.250.31.254 (129.250.0.0 and 129.250.31.255 not used) subnet B: 129.250.32.1-125.250.63.254 subnet C: 129.250.64.1-125.250.95.254 subnet D: 129.250.96.1-125.250.127.254 subnet E: 129.250.128.1-125.250. 159.254b> bit throwing algorithm (that is, to calculate the number of zeros for the next digit in the subnet mask, n indicates the number of zeros): This algorithm needs to know the number of ip addresses for each subnet !!! 2n-2> = number of ip addresses in the required subnet/255 cases: the number of hosts in each subnet of a Class B subnet must reach 60X255 (approximately equivalent to X. Y.0.1 ~ X. Y.59.254. Www.2cto.com Description: The subnet mask of Class B is: 11111111.11111111.20.2.16.00000000 2n-2> = 60 evaluate n = 6 The subnet mask in all subnets the next bit has 6 0, that is, 2 1, so the subnet mask of the subnet is: 11111111.111111.1111600.00000000 = 201710000192.0 obtain the subnet mask and then calculate the ip address range of each subnet. 4. communication between different subnets communication between different subnets is not allowed directly through a layer-2 switch. A layer-2 switch only has the packet forwarding function and has no routing function, to implement communication between different subnets, we need to use the so-called vswitch with the routing function, that is, a layer-3 Switch, also known as a routing switch. Or directly use the vro. You can also use the proxy method: Enable RRAS on a Windows Server 2003 Server with dual NICs, and take an IP address from the two subnet IP address ranges (for example, the IP addresses of "subnet A", "192.168.0.33" and "subnet B", and "192.168.0.65 ") bind the two NICs respectively. Set all clients in subnet A to "192.168.0.33", and all clients in subnet B to "192.168.0.65 ". Now, the two subnets can not only access each other, but also effectively reduce the burden on the entire network and greatly improve the network utilization.