A VTS Internet Server, actually includes two servers: an HTTP server built into the System Library layer and a VTS Internet Server built into the VTS engine itself.
The job of the HTTP server is to respond to non-VIC HTTP requests. When Internet Explorer (IE) is pointed at the URL for a server and realm, (e.g. https://dataonline1.trihedral.com/demo) the VTS engine routes the request to HTTP server. The HTTP server challenges the user for authentication credentials, resulting in a username/password dialog box appearing on the machine running IE. Once the user has supplied authentication credentials, IE re-submits the request to the HTTP server and the HTTP server then validates the credentials against those held by SecurityManager in the application that the realm is configured on.
After the HTTP server has authenticated the user, it sends a message back to IE. The screen displays that message informing the user the VIC is being downloaded. If the most current VIC is already installed on the client machine, the download is skipped and the VIC is simply instantiated.
If the VTS Internet Server has been configured for redundant VTS Internet Client operation, additional information will be sent from the HTTP server to allow the VIC to function in a redundant mode. Failure to receive the extra information causes the VIC to behave in a non-redundant manner, so that an initial connection to an older server will function in legacy mode.
The extra information consists of:
• Display Manager state information
• a list of VTS Internet Servers
• redundant operation parameters