Question

Write a program to demonstrate subnetting and find the subnet masks.

Answer 1

Program to show subnetting and find the subnet masks.

import java.util.Scanner;  

class Subnet{ public static void main(String args[])

{  

Scanner  = new Scanner(System.in);  

System.out. println (“Enter the ip address: “);  

String = sc. next Line();  

String = ip. split(“\\.”); .  

String split_bip[] = new String[4];  

split binary ip String bip = “”;  

for(int i=0;i<4;i++)

split_bip[i] = appendZeros (Integer.toBinaryString(Integer.parseInt

(split_ip[i])));  

}

Answer 2

A program to implement sub netting and find the su bnet masks:

In Java,

import java.util.Scanner

class Sub_net{

public static void main(String args[]){

Scanner sc = new Scanner(System.in);

System.out.print(“IP address: “);

String ip = sc.nextLine();

String split_ip[] = ip.split(“\\.”);  

String split_bip[] = new String[4];

String bip = “”;

for(int i=0;i<4;i++){

split_bip[i] =appendZeros(Integer.toBinaryString(Integer.parseInt(split_ip[i])));  

bip += split_bip[i];

}

System.out.println(“IP in binary = “+bip);

System.out.print(“Enter the addresses: “);

int n = sc.nextInt();

int bits = (int)Math.ceil(Math.log(n)/Math.log(2));

System.out.println(“Number of bits required = “+bits);

int mask = 32-bits;

System.out.println(“The sub net mask = “+mask);

int fbip[] = new int[32];

for(int i=0; i<32;i++) fbip[i] = charAt(i)-48;

for(int i=31;i>31-bits;i–)

fbip[i] &= 0;

String fip[] = {“”,””,””,””};

for(int i=0;i<32;i++)

fip[i/8] = new String(fip[i/8]+fbip[i]);

System.out.print(“First address is = “);

for(int i=0;i<4;i++){

System.out.print(Integer.parseInt(fip[i],2));

if(i!=3) System.out.print(“.”);

}

System.out.println();

int lbip[] = new int[32];

for(int i=0; i<32;i++) lbip[i] = charAt(i)-48;  

for(int i=31;i>31-bits;i–)

lbip[i] |= 1;

String lip[] = {“”,””,””,””};

for(int i=0;i<32;i++)

lip[i/8] = new String(lip[i/8]+lbip[i]);

System.out.print(“Last address is = “);

for(int i=0;i<4;i++){

System.out.print(Integer.parseInt(lip[i],2));

if(i!=3) System.out.print(“.”);

}

System.out.println();

}

static String appendZeros(String s){

String temp = new String(“00000000”);

return temp.substring(s.length())+ s;

}

}