s-Server can be used over the internet thanks to SQLstream's WebAgent, which functions as a simple, miniature web server. The WebAgent accepts HTTP requests representing SQL queries and sends those queries to an s-Server. Query results are then delivered as JSON objects in the WebAgent's reply. (See json.org for more details on JSON objects.)
WebAgent is an integral part of both StreamLab and s-Dashboard. In both cases, it provides a WebSocket interface for sending streaming data to the client. Additionally, for StreamLab, the WebAgent includes some server-side components (e.g. SQL orchestration, discovery, and the scrutinizer). The WebAgent is also delivered as part of the SQLstream Client Tools.
For more information about WebAgent, see Using s-Server over the Internet.