Not very good at working out subnet masks. Have been told by a customer that the IP range that he has given me is running on a 24 bit subnet mask. So what should I set it to? 255.255.255.??
IP address range starts 10.60.15.0, 10.60.15.1 is the gateway.
Thanks
Andrew.
An IP address is the way IP distinguishes computers (or more specifically Interfaces) that exist on the same network. On a network you simply cannot have two computers sharing the same IP address, as this creates havoc when trying to send data to the correct location. All computers that are ‘on’ the Internet (or LAN) need different IP addresses. You have probably seen addresses in the form 128.211.23.45. This is a 32-bit number separated into 4 8-bit parts. The four parts are similar to a phone number.
In an IP address there are 2 parts, the network and the host identifiers. There are five classes of network addresses, but only three are usable for the internet or local area networks. The other two are for something else such as multicast and experimental use.
Just as in a phone number say 01273 195929 the 01273 is the exchange number and the last 6 digits are the number within that exchange.
Class A nnn.hhh.hhh.hhh
Class B nnn.nnn.hhh.hhh
Class C nnn.nnn.nnn.hhh
where n’s=network identifier, h’s=host identifier
With a class A network, there can be 126 networks and about 16.5 million hosts per subnet
With a class B network, there can be about 64 thousand networks and 64 thousand hosts per subnet
With a class C network, there can be about 16.5 million networks and 254 hosts per subnet
The subnet mask signifies the network address. So a 24 bit mask or 255.255.255.0 means that the network address in your example of 10.60.15.1 is 10.60.15 and the last 8 bits are reserved for the host i.e 1 to 254
The 255 in the subnet mask address, signifies which byte (8 bits) is the network address.
