To read an introduction to the first release of the open-source DiaStar™ Server (DSS), learn how to configure it, understand how it handles call flow, and find out how to access more details, see Introduction to the DiaStar™ Server Release 1.0.
Summary
When used with open source telephony clients, the DSS acts as a network interface to the Public Switched Telephone Network (PSTN). Although it is possible to connect an application server, such as Asterisk, directly to one or more PSTN interface boards, placing this functionality in a separate server can provide the following benefits:
- Scalability — Media functions can be either performed by the telephony application or offloaded to the DSS to enable higher channel counts than are possible in a single-server system
- Redundancy — A system can be configured without a single point of failure. If interrupted, the system switches to a backup component.
- Reliability — Dialogic technology is engineered to provide high reliability and availability. Adding a DSS might require some initial downtime to configure Asterisk, but adding chan_woomera clients for Asterisk should not require downtime.
- Control – Placing functionality into separate, smaller components provides greater control over the functioning of each individual component
The DSS leverages Dialogic’s proven media processing software and PSTN network interface technology. The full suite of PSTN protocols (ISDN, CAS, and SS7 over T1/E1) found in the Dialogic® Global Call API can be used with DSS. In addition, Dialogic’s many years of experience in efficiently converting media streams from Time Division Multiplexed (TDM) to Internet Protocol (IP) helps to provide very low latency.
For telephony client connectivity, the DSS uses a communications protocol based on Woomera, an open source, IP-based signaling protocol for Local Area Network (LAN) environments. The protocol used by the DSS is a readable text-based protocol that is easy to understand and debug, and that uses Real Time Protocol (RTP) to deliver media streams efficiently.
Read Introduction to the DiaStar™ Server Release 1.0 for more details.