CYCLIC REDUNDANCY CHECK


AIM:
           To write a program for TCP connection establishment.

ALGORITHM:
SERVER:

    STEP 1: Start
    STEP 2: Declare the variables for the socket
    STEP 3: Specify the family, protocol, IP address and port number
    STEP 4: Create a socket using socket() function
    STEP 5: Bind the IP address and Port number
    STEP 6: Listen and accept the client’s request for the connection
    STEP 7: Establish the connection with the client
    STEP 8: Display the dividend and divisor
    STEP 9: Display the dividend with zero appended
    STEP 10: Display the quotient, remainder and CRC value
    STEP 11: Close the socket
    STEP 12: Stop
CLIENT:
    STEP 1: Start
    STEP 2: Declare the variables for the socket
    STEP 3:  Specify the family, protocol, IP address and port number
    STEP 4: Create a socket using socket() function
    STEP 5: Call the connect() function
    STEP 6: Read the dividend and divisor
    STEP 6: Display the quotient, remainder and CRC value
    STEP 6: Close the socket
    STEP 7: Stop

SOURCE CODE:
SERVER:

#include<stdio.h>
#include<string.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<netdb.h>
#define SERV_TCP_PORT 5035
int main(int argc, char **argv)
{
int sockfd,newsockfd,clength;
struct sockaddr_in serv_addr,cli_addr;
char a[30],b[30],c[30]={0},q[30]={0},p[30]={0},np[30]={0},crc[10]={0},r[30]={0};
int n,m,i=0,j=0,count=0,k=0,l=0,ir=0,ip=0,cou=0,u=0,w=0,nk=0;
sockfd=socket(AF_INET,SOCK_STREAM,0);
serv_addr.sin_family=AF_INET;
serv_addr.sin_addr.s_addr=INADDR_ANY;
serv_addr.sin_port=htons(SERV_TCP_PORT);
printf("\n Binded...");
bind(sockfd,(struct sockaddr*)&serv_addr,sizeof(serv_addr));
listen(sockfd,5);
clength=sizeof(cli_addr);
newsockfd=accept(sockfd,(struct sockaddr*)&cli_addr,&clength);
read(newsockfd,a,30);
read(newsockfd,b,30);
m=strlen(b);
printf("\n Dividend:%s",a);
printf("\n Divisor:%s",b);
strcpy(c,a);
for(i=0;i<m-1;i++)
strcat(c,"0");
printf("\n Dividend with zero appended:%s",c);
for(i=0;i<m;i++)
{
    p[k++]=c[i];
    if(strlen(p)==m)
    q[j++]='l';
}
for(i=0;i<strlen(c);)
{
    if(p[nk++]==b[l++])
       r[ir++]='0';
    else
       r[ir++]='l';
    count++; 
if(count==strlen(b)&&i<(strlen(c)-1))
 {
     ip=0;
     for(u=0;u<strlen(b);u++)
     {
       if(r[u]=='l')
        {
         for(n=u;n<strlen(b);n++)
         {
             np[ip++]=r[n];
            r[n]='0';
            cou++;
         }
       }
    }
   count=0;
   nk=0;
   l=0;
   ir=0;
   if(cou!=strlen(b))
   {
    if((strlen(b)-cou)==(strlen(c)-(i+1))||(strlen(b)-cou)<(strlen(c)-(i+1)))
    {
    while(cou!=strlen(b))
     {
        i++;
        np[ip++]=c[i];
        cou++;
        w++;
     }
     strcpy(p,np);
     for(u=0;u<w-1;u++)
     q[j++]='0';
     if(w!=0)
     {
        i-=strlen(np);
        w=0;
     }
    }
    else
   {
    for(;i+1<strlen(c);)
    {
       i++;
       np[ip++]=c[i];
       w++;
    }
  
 if(ip<strlen(b))
   {
   for(;ip<strlen(b);)
   np[ip++]=' ';
   }
   strcpy(r,np);
   for(u=0;u<w-1;u++)
   q[i++]='0';
   i=strlen(c);
   w=0;
}
}
   if(cou=strlen(b))
   {
      q[j++]='l';
      cou=0;
   }
   ip=0;
   cou=0;
}
    i++;
}
printf("\n Quotient=%s",q);
printf("\n Remainder=%s",r);
for(i=strlen(r)-(m-1);i<=strlen(r);i++)
crc[w++]=r[i];
printf("\n CRC values: %s\n",crc);
write(newsockfd,q,30);
write(newsockfd,r,30);
write(newsockfd,crc,10);
close(sockfd);
return 0;
}

CLIENT:
#include<stdio.h>
#include<string.h>
#include<sys/types.h>
#include<sys/socket.h>
#include<netinet/in.h>
#include<netdb.h>
#define SERV_TCP_PORT 5035
int main(int argc,char * * argv)
{
       int sockfd;
       struct sockaddr_in serv_addr;
       struct hostent *server;
       char a[30],b[30],q[30],r[30],crc[10];
       sockfd=socket(AF_INET,SOCK_STREAM,0);
       serv_addr.sin_family=AF_INET;
       serv_addr.sin_addr.s_addr=inet_addr("127.0.0.1");
       serv_addr.sin_port=htons(SERV_TCP_PORT);
       connect(sockfd,(struct sockaddr*)&serv_addr,sizeof(serv_addr));
       printf("\nEnter the dividend:");
       scanf("%s",a);
       printf("\nEnter the divisor:");
       scanf("%s",b);
       write(sockfd,a,30);
       write(sockfd,b,30);
       printf("\n");
       printf("\nServer result:");
       read(sockfd,q,30);
       read(sockfd,r,30);
       read(sockfd,crc,10);
       printf("\n\nQuotient=%s",q);
       printf("\n\nRemainder=%s",r);
       printf("\n\nCRC values=%s\n",crc);
       close(sockfd);
       return 0;
}

OUTPUT:
SERVER:

CLIENT:

RESULT:
    Thus the program for Cyclic Redundancy Check was executed and the output was
verified.

Previous
Next Post »

Still not found what you are looking for? Try again here.