Data formatting for Mini-project: Cellular Tower logger

How I compress data for UDP.c

int format(){
  data  = "C,";
      data += ultoa(seq, numberBuffer, 36);
      data += ','; data += String(ultoa(strtoul(networkCode.c_str(), (char **)NULL, 10), numberBuffer, 36));
      data += ","; data += String(utoa (networkInfo.TAC,                                 numberBuffer, 36));
      data += ","; data += String(ultoa(networkInfo.ECI,                                 numberBuffer, 36));
      data += ','; data += String(utoa (
        strtoul(networkSignalQuality.csq.c_str(), (char **)NULL, 10), 
        numberBuffer, 
        36
      ));
      /****** /Format Data *****/
      Serial.print("\r\n* Data -> "); Serial.println(data);
       
      // UDPSend udp = AISnb.sendUDPmsg(serverIP, serverPort, strlen(data), data,MODE_STRING);
      // udp = AISnb.sendUDPmsgStr(serverIP, serverPort, "Test,52003,0Xa3c3,0X9c802a3");
      
      udp = AISnb.sendUDPmsgStr(serverIP, serverPort, data);

      /****** Format GPS Data *****/
      if(isGPSGet){
        data = "G,";
        data += ultoa(seq, numberBuffer, 36); data += ',';
        data += Lat; data += ',';
        data += Lng;
        Serial.print("\r\n* GPS  -> "); Serial.println(data);
        udp = AISnb.sendUDPmsgStr(serverIP, serverPort, data);
      }
}