There are few steps which we have to follow to implement Push Notification.

Step 1: First we will write the api to get token and device type . Here is the controller code of push notification.

public function pushNotification() {
        $validator = Validator::make(Request::all(), [
                    'userId'=>'required',
                    'accessToken'=>'required',
                    'senderId'=>'required',
                    'token'=>'required',
                    'deviceType'=>'required'
        ]);
        if ($validator->fails()) {
            #display error if validation fails      

            $this->status = 'Validation fails';
            $this->message = 'arguments missing';
        } else {
            $userId =Request::get('userId');
            $accessToken=Request::get('accessToken');
            $senderId=Request::get('senderId');
            $token=Request::get('token');
            $deviceType=Request::get('deviceType');
            $checkUserStatus =User::where('id','=',$userId)->first();
            if(!empty($checkUserStatus)){
                if( $deviceType=='Android'){
                    $setMessage='You have a new activity on KarmaCircles.';
                    $pushNotificationStatus=NotificationHelper::androidPushNotification($token,$setMessage);
                    $this->status = $pushNotificationStatus;
                    $this->message = 'Push Notification Message';
                }else{
                    $pushNotificationStatus=NotificationHelper::iphonePushNotification($token,$setMessage);
                    $this->status = $pushNotificationStatus;
                    $this->message = 'Push Notification Message';
                }
            }else{
                $this->status = 'Failure';
                $this->message = 'There is no such user available';
            }
        }
        return Response::json(array(
            'status'=>$this->status,
            'message'=>$this->message
        ));
       }

Now we use NotificationHelper to perform notification.

Step 2:

In NotificationHelper.php the code is:

  /**
     * Apple Push Notification Services (APNS)
     *
     * @param   string  device_token
     * @param   string  message
     * @return  string  status  success|failure
     */
     public static function iphonePushNotification($device_token, $msg = null) {


        // Set private key's passphrase_local cert file path
        $passphrase = PASSPHRASE;
        $local_cert = LOCAL_CERT_PATH;
        $streamContext = stream_context_create();
        stream_context_set_option($streamContext, 'ssl', 'local_cert', $local_cert);
        stream_context_set_option($streamContext, 'ssl', 'passphrase', $passphrase);
        $fp = stream_socket&_client('ssl://gateway.sandbox.push.apple.com:2195', $error, $errorString, 20, STREAM_CLIENT_CONNECT, $streamContext);
        // Open a connection to the APNS server

        if (!$fp) {

            $status = "failure";

        } else {

                // iPhone Device Token Without Any Spaces
                $device_token = str_replace(' ', '', $device_token);

                // Set badge
                $badge = 1;

                // Check if device token not empty
                if (!empty($device_token)) {
                    // Create the payload body
                    $body['aps'] = array('alert' => $msg, 'badge' => $badge, 'sound' => 'default');

                    // Encode the payload as JSON
                    $payload = json_encode($body);
                    try {

                        // Build the binary notification
                        $msg = chr(0) . pack('n', 32) . pack('H*', $device_token) . pack('n', strlen($payload)) . $payload;

                        // Send it to the server
                        $result = fwrite($fp, $msg, strlen($msg));

                        Log::info("ios result ::". var_export($result,TRUE) );


                    } catch(Exception $e) {
                        //echo "1. Exception: " . $e -> getMessage() . "<br />\n";
                        Log::info("ios error ::". $e -> getMessage() );
                    }

                }

            $status = 'success';
        }
        fclose($fp);

        Log::info("returning  ::". $status );

        return $status;

    }

By this way we can implementing push notification using laravel 4.x