Answer to Question #321226 in Computer Networks for Prem

Question

What is the Network ID, Broadcast Address, First Usable IP, or Last Usable IP on the sub-network

that the node 192.168.1.15/26 belongs to?

Answer 1

Each network device should have IP address for working, i.e. for send and receive information, just like anybody should have the post address for send and receive the mail or any things via postal service.

There are many-many persons, firms, providers, and so on, who need the IP addresses, so, the IP addresses’ all range divided into many networks/subnetwork. 

Network ID

Network ID is the portion of an IP address that identifies the network for a given host, i.e. identifies the network on which a host resides. For clearly understanding now provide example on 192.168.1.0/24 network.

/24 means that Subnet Mask: 255.255.255.0

IP address range for hosts is 192.168.1.1 – 192.168.1.254. We can see that host IPs changes from 1 to 254, so, the hosts ID is, for example, 0.0.0.10. But stay unchangeable the 192.168.1. – it is the Network ID – 192.168.1.0.

Broadcast Address

Each IP range/network has the borders, the start/first IP and last IP. First IP and last IP are not usable for hosts. If the first IP determinate the “Network Address”, the last IP is a “Broadcast Address”. In other words the highest address in the subnet your IP address falls in is the broadcast address.

A broadcast address used to target all systems on a specific subnet network instead of single hosts, i.e. broadcast address allows information to be sent to all machines on a given subnet rather than to a specific machine.

First Usable IP, or Last Usable IP

As wrote above the from provided IP range the first IP and last IP are not usable for hosts. The remainders are in use. First IP from reminder range is “first usable IP”, the last IP from reminder range is “last usable IP”.

           

For easy understanding will provide example on 192.168.1.15/26

/24 means that Subnet Mask: 255.255.255.192

Our IP range:                        192.168.1.0 – 192.168.1.63

Network Address:                192.168.1.0

Broadcast Address:             192.168.1.63

Total Number of Hosts:       64

Usable Host IP Range:         192.168.1.1 - 192.168.1.62

Number of Usable Hosts:    62

First Usable IP:                     192.168.1.1

Last Usable IP:                     192.168.1.62

 

192.168.1.15/26 node is a host which has IP address from selected network.