ARP and RARP in C , C program to implement ARP

Algorithm:

Step 1: Initialize the string of ip addresses
Step 2: For every ip address, assign an ethernet address
Step 3: To Perform ARP, enter the ip address
Step 4: The equivalent ethernet address is displayedStep
Step 5: If the ethernet address is not found, then 'not found' message is displayeS
Step 6: To Perform RARP, enter the ethernet address
Step 7: The equivalent ip address is displayed
Step 8: If the ip address is not found, then 'not found' message is displayed
Step 9: Provide option to perform both ARP and RARP
Step 10:Choose Exit option to terminate the program

Program:


#include<stdio.h>
#include<string.h>
#include<conio.h>
main()
{
char ip[10][20]={"192.168.0.64","192.168.0.60","192.168.0.68","132.147.3.3"};
char et[10][20]={"00_A8_00_40_8E_FS","00_16_17_31_8e_22","00_16_17_31_8E_F7","00_16_17_31_8E_08"};
char ipaddr[20],etaddr[20];
int i,op;
int x=0,y=0;
clrscr();
while(1)
{
printf("\n\n 1.ARP 2.RARP 3.EXIT");
printf("\n enter the choice");
scanf("%d",&op);
switch(op)
{
case 1:
printf("\n enter ip address");
scanf("%s",ipaddr);
for(i=0;i<=20;i++)
{
if(strcmp(ipaddr,ip[i])==0)
{
printf("Ethernet address is%s",et[i]);
x=1;
} }
if(x==0)
printf("invalid ip address");
x=0;
break;
case 2:
printf("enter ethernet address");
scanf("%s",etaddr);
for(i=0;i<=20;i++)
{
if(strcmp(etaddr,et[i])==0)
{
printf("IP address is %s",ip[i]);
y=1;
} }
if(y==0)
printf("Invalid ethernet address");
y=0;
break;
case 3:
exit(0);
} } }