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Virtual Modem PRO - How to connect 2 computers using Virtual Modem?

In order to connect 2 PCs using Virtual Modem PRO you must install it on both computers, set up one computer as a client (the one which will initiate connection, i.e. dial up to remote host) and the second one as a server (it will wait for incoming call and respond to it). Apart from creating virtual modems you must configure applications that will use virtual modems to establish the link between two computers. Here we will describe the standard Windows Hyperterminal and dial-up configuration wizard.

Let's assume that you have installed Virtual Modem PRO into 2 computers on the Internet/WAN/LAN and one has IP 192.168.0.1 while the second PC has IP 192.168.0.2. We are going to configure the host with IP 192.168.0.1 as a server and 192.168.0.2 as a client. Please, note that mentioned IPs are taken solely for example. You must provide actual static IP addresses that are assigned to your PCs. If not sure, please, consult your Internet provider or system administrator. The final configuration is shown on the image below.

Setting up Virtual Modem PRO as a server

  • Select Add/Remove Modems tab in Configuration Panel.

  • Select the serial communication port which virtual modem will be assigned to from "Modem serial port" combo-box. Let's select COM 10 for example. Please, note that you will not be able to select port which is already in use.

  • Specify TCP port which will be used to accept incoming connections on. You may type any number from 1 to 65535, however, make sure that it doesn't interfere with other network services (DNS, Mail, HTTP, SMB, etc.). Let's select TCP port equal to 12345.

  • Click "Add modem" button.
  • On successful creation, you will see confirmation message:

To check modem's settings switch to Statistics tab:

Once the virtual modem is successfully added, it may accept incoming calls. To be able to initiate the call, you must specify remote host IP address and port (i.e. configure it as a client).

Setting up Virtual Modem PRO as a client

  • Select Add/Remove Modems tab in Configuration Panel area.

  • Select the serial communication port which virtual modem will be assigned to from "Modem serial port" combo-box. Let's select COM 11 for example. Please, note that you will not be able to select port which is already in use.
  • Click "Add modem" button.
  • Now, select the newly created modem in the left panel and type remote host IP address (or Fully Qualified Domain Name) and TCP port in the corresponding "Host:port" textfields. Please, note that TCP port must match "Server port" value set at the remote side. In our case you should type 192.168.0.1:12345

  • Click "Set" button.

To check modem's settings switch to Statistics tab:

Virtual Modem PRO is a middleware, which acts as a man-in-the-middle between your application and Internet. Since each particular application is different, we will describe how to set up standard Windows Hyperterminal utility ("Program File" -> "Accessories" -> "Communications" -> "HyperTerminal") and use Windows dial-up connection wizard to connect two computers.

Setting up HyperTerminal

Make sure that it is installed on both of your computers. Client and server-side settings are essentially the same but differ only in communication settings which you assign to the terminal. We will emphasize the difference below. To configure HyperTerminal, please, do the following steps:

  • Launch Hyperterminal using "Start" menu.
  • Type in any name for this connection. For instance type "Server" for the computer that will accept phone call and "Client" to the computer that will initiate the call. Click "Ok" button to proceed.

  • In "Connect using" combo-box select "COM10" and "COM11" options for the server and client sides respectively. Click "Ok" button when done.

  • In the next dialog you will be asked to specify serial port connection parameters, however you may skip this step since Virtual Modem PRO will set them automatically during handshaking process.
  • Once the configuration parameters for both terminals are set you may type Hayes commands to establish connection. Please, note if you are using your own application then you won't need to type any commands at all but press necessary buttons or select options to establish the link. For the HyperTerminal, however, we will create the link manually. Type in "ATDT192.168.0.10:12345" at the client-side and press "Enter". When you see "RING" at the client side, type "ATA" and press "Enter" to accept the call. This will establish connection between two hosts. Modems will switch to data mode. For more information about the Hayes commands, please, consult Supported Hayes Commands page.

Setting up connection using dial-up connection wizard

  1. Server-side modem (the host that will accept incoming calls)

    • Launch connection wizard using "Start" menu ("START" -> "Settings" -> "Control Panel" -> "Network Connections" -> "Create a new connection")

    • Select "Set up an advanced connection" option

    • Select "Accept incoming connections" option

    • Choose virtual modem that will accept the call

    • Press "Next" button at the next dialog to proceed

    • Select the user for the authorization process. If chosen user account has a password, you should specify it when creating client-side connection

    • Make sure that "Internet Protocol (TCP/IP)" option is enabled and click "Next" button to proceed

    • Finally, click "Finish" button to complete "New connection wizard" dialog
  2. Client-side modem (the host that will initiate the call)

Launch connection wizard using "Start" menu ("START" -> "Settings" -> "Control Panel" -> "Network Connections" -> "Create a new connection")

Enable "Connection to the network at my workplace" option and click "Next"

Enable "Connection to the network at my workplace" option and click "Next"

Select "Dial-up connection" option

Select virtual modem that is connected to COM11

Type any name for this connection and click "Next" button

Type in server's IP address and TCP port to connect to. In our case "192.168.0.10:12345"

Click "Finish" button to finalize the wizard dialog

Once client-side modem is configured you may call to the server. For that you must specify username, which you have selected at server-side connection wizard dialog and the password if required.