# Terminal adapter #### ISDN Terminal Adapter An ISDN Terminal Adapter (TA) is a device that connects digital ISDN lines to traditional analog devices such as telephones, fax machines, or modems. Unlike a modem, which converts digital data into analog for transmission across standard phone lines, an ISDN TA directly connects devices to the digital ISDN network, enabling higher data transfer rates. The TA performs protocol conversion and signaling, ensuring seamless communication between digital networks and analog equipment. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://isdn.learn-telecom.com/devices/terminal-adapter.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.