EX9188E series are the embedded controllers designed to meet the most common requirements of Internet or Ethernet applications. An on-board 10base-T port is equipped with a RJ-45 connector, which let you connect to the network through a cable. It is powered by 80188-40 processor with 512K bytes of static RAM and 512K bytes of flash memory. RS232 and RS485 ports are provided. EX9188E is can be treated as a RS232 to Ethernet converter. The central computers can control all the RS232 ports through Ethernet with the help of EX9188E. RS232 devices can be hooked to the closest network hubs and link to the central computer. After linking all these devices together, the software application would have to develop in order to access them. In general, it is more difficult to develop a TCP/IP based application program than COM port based program. To get a software “VSP(Virtual Serial Port) or VirCom” from Web/CD of TOPSCCC or Easy net co. that It can be used to take care of network protocol layers and let the host computer visualize COM ports of EX9188E. It makes the host computer have virtual COM ports which are actually mounted in EX9188E. Therefore, the software applications can be COM port based and the old COM port based application can still be used. The advantages can be concluded that it provides a easy interface for software development and it also keeps the old system going without program modification.