didReceiveAuthenticationChallenge

for network Authentication 

-(void)connection:(NSURLConnection *)connection didReceiveAuthenticationChallenge:(NSURLAuthenticationChallenge *)challenge{

    if ([challenge previousFailureCount] == 0) {

        NSURLCredential *newCredential;

        newCredential=[NSURLCredential credentialWithUser:@"User_Name"

                                                 password:@"Password"

                                              persistence:NSURLCredentialPersistenceNone];

        [[challenge sender] useCredential:newCredential

               forAuthenticationChallenge:challenge];

        

    } else {

        

        [[challenge sender] cancelAuthenticationChallenge:challenge];

        // inform the user that the user name and password

        // in the preferences are incorrect

    }

    

}