How to Identify Unknown Communications Protocol
- 1). Open the program or application for which you want to determine the communications protocol. Run the program or application so that its unknown protocol is in use.
- 2). Click the "Start" button on the Windows 7 PC desktop. Click "Programs" and click "Accessories." Right-click on the command line icon in the menu that appears and click "Run as Administrator." The command prompt window will appear.
- 3). Type "netstat -abv" and press the "Enter" key. Locate the name of the program executable for which you require protocol information. It will be inside square brackets below one of the blocks of information displayed in the command line output.
- 4). Note the number after the colon at the end of the computer name. The computer name is at the top of the information block in the "Local Address" column that includes the name of the program executable. Note the number after the colon at the end of the hostname or IP address to the immediate right of the "Local Address" computer name. Note the value listed in the "Proto" column of the information block (either "TCP" or "UDP").
- 5). Open a web browser such as Internet Explorer or Firefox. Connect to the "Ports.My-Addr.Com: Port Search" website (see Resources). If the program using the unknown protocol runs as a service to which other computers or devices connect, type the number noted earlier that was listed after your computer name into the text box below the "Legend" label displayed in the middle of the page. Otherwise type the other number noted earlier in the text box. Click the radio button corresponding to the value that was noted earlier in the "Proto" column in the command line output (either "TCP" or "UDP"). Tap the "Enter" key.
- 6). View the information for the port. The information will identify the unknown protocol.
