In order to find network id (NID) of a Subnet, one must be fully acquainted with the Subnet mask.
It is used to find which IP address belongs to which Subnet. It is a 32 bit number, containing 0’s and 1’s. Here network id part and Subnet ID part is represented by all 1’s and host ID part is represented by all 0’s.
If Network id of a entire network = 126.96.36.199 (it is class C IP). For more about class C IP see Classful Addressing.
In the above diagram entire network is divided into four parts, which means there are four subnets each having two bits for Subnet ID part.
Subnet-1: 188.8.131.52 to 184.108.40.206 Subnet-2: 220.127.116.11 to 18.104.22.168 Subnet-3: 22.214.171.124 to 126.96.36.199 Subnet-4: 188.8.131.52 to 184.108.40.206
The above IP is class C, so it has 24 bits in network id part and 8 bits in host id part but you choose two bits for subnet id from host id part, so now there are two bits in subnet id part and six bits in host id part, i.e.,
24 bits in network id + 2 bits in subnet id = 26 (1's) and 6 bits in host id = 6 (0's)
Subnet Mask = 11111111.11111111.11111111.11000000 = 255.255.255.192
If any given IP address performs bit wise AND operation with the subnet mask, then you get the network id of the subnet to which the given IP belongs.
If IP address = 220.127.116.11 (convert it into binary form) = 11000001.00000001.00000010.10000001 Subnet mask = 11111111.11111111.11111111.11000000 Bit Wise AND = 11000001.00000001.00000010.10000000 Therefore, Nid = 18.104.22.168
Hence, this IP address belongs to subnet:3 which has Nid = 22.214.171.124
If IP address = 126.96.36.199 (convert it into binary form) = 11000001.00000001.00000010.01000011 Subnet Mask = 11111111.11111111.11111111.11000000 Bit Wise AND = 11000001.00000001.00000010.01000000 Therefore, Nid = 188.8.131.52
Hence, this IP address belongs to subnet:2 which has Nid = 184.108.40.206
- Computer Network | Introduction to variable length subnet mask (VLSM)
- Computer Network | IPv4 classless Subnet equation
- C Program to find IP Address, Subnet Mask & Default Gateway
- Computer Network | Simple network management protocol (SNMP)
- Computer Network | Integrated services digital network (ISDN)
- Computer Network | Types of Network address translation (NAT)
- Computer Network | Synchronous Optical Network (SONET)
- Computer Network | Packet flow in the same network
- Computer Network | Packet flow in different network
- Computer Network | Network address translation (NAT)
- Computer Network | Evolution of Network
- Computer Network | Network Simulator 3
- Computer Network | Network goals
- Computer Network | How ARP works?
- Computer Network | Dynamic NAT (on ASA)
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