# RTTP

Caplin’s Real Time Text Protocol (RTTP) is the streaming protocol used by client applications to communicate with [Caplin Liberator](index.md) via [StreamLink](../streamlink/index.md). RTTP is used to stream data to clients (such as updates to financial instrument prices), and to exchange messages with clients to support trading and other client - platform interactions.

RTTP is a robust text-based protocol that operates over intranets, the web, and over private networks (directly via TCP/IP). When operating over WANs, intranets and the web, RTTP is typically encapsulated in HTTP, or in HTTPS, to provide the highly secure messaging required by many financial applications.

RTTP features:

* Automatically tunnels between clients and Liberator, through firewalls and proxy servers, with no special TCP/IP port requirements.
* Uses persistent virtual connections, providing rapid and seamless recovery from transient connection loss.
* Designed to utilise bandwidth between Liberator and its clients extremely efficiently.
* Can handle information in various formats, including structured records, news headlines and news stories; containers and directories.

For more information about RTTP data formats, see [Data Types](../datasource/datasource-data-types.md) in the DataSource section.

For more on supported connection types, [StreamLink connection types](../streamlink/streamlink-connection-types.md).