Algorius Net Viewer Manual
Running over HTTPS (SSL)

Running over HTTPS (SSL)

You can use SSL for the Web server using the Stunnel application.

To enable SSL, follow these steps:

  • In the application settings on the Web server tab, enable Web access and specify an address, for example, http://+:3234/, where 3234 is a port for HTTP connection. The symbol ‘+’ in the address means accessibility by any local IP or host name. See Address String Format for more information.
  • Install the Stunnel application. The latest version is available at
  • In STunnel, select the menu ConfigurationEdit Configuration and uncomment the [https] section, it should look something like this:

; TLS front-end to a web server


accept = 443

connect = 3234

cert = stunnel.pem

; "TIMEOUTclose = 0" is a workaround for a design flaw in Microsoft SChannel

; Microsoft implementations do not use TLS close-notify alert and thus they

; are vulnerable to truncation attacks

TIMEOUTclose = 0

  • The accept parameter specifies the port for HTTPS connections (the default is SSL port 443).
  • The connect parameter specifies the port selected in Algorius Net Viewer for HTTP connections.
  • In STunnel, select the menu ConfigurationReload Configuration and check that the configuration has loaded without errors. Configuration successful should appear in the STunnel window.
  • Check that the Web server opens in a browser at https://localhost
  • Check that the Web server is available to other users. Instead of localhost, specify the address of the computer with the Web server (IP or DNS name).
  • The browser may return an error about the certificate, because STunnel generates a self-signed certificate by default. In this case, you need to choose to trust the certificate of this site in the browser. Or purchase a trusted certificate and upload it to STunnel if you need it.