WHAT IS DDS?
All together, the local stores give applications the illusion of having access to the entire global data space. This is only an illusion; there is no global place where all the data lives. Each application locally stores only what it needs and only for as long as it needs it. DDS deals with data in motion; the global data space is a virtual concept that is really only a collection of local stores. Every application, in almost any language, running on any system, sees local memory in its optimal native format. The global data space shares data between embedded, mobile, and cloud applications across any transport, regardless of language or system, and with extremely low-latency.
QUALITY OF SERVICE
WHAT IS DDS?
The behavior of data communication can be configured with flexible Quality of Service( QoS) specifications including reliability, system health( liveliness), and even security. In a real system, not every end-point needs every item in your local store. DDS is smart about sending just what it needs. If messages don’ t always reach their intended destinations, the middleware implements reliability where needed. When systems change, the middleware dynamically figures out where to send which data, and intelligently informs participants of the changes. If the total data size is huge, DDS intelligently filters and sends only the data each end-point really needs. When updates need to be fast, DDS sends multicast messages to update many remote applications at once. As data formats evolve, DDS keeps track of the versions used by various parts of the system and automatically translates. For security-critical applications, DDS controls access, enforces data flow paths, and encrypts data on-the-fly.
The true power of DDS emerges when you specify all of these things simultaneously, at extremely high speeds, and in a very dynamic, demanding, and unpredictable environment.
MITRE is a strong supporter of standards-based solutions and approaches to foster interoperability today and evolution into the future. DDS has demonstrated its ability to play a major role in addressing distributed data distribution challenges faced by our sponsors and those they depend on in the Industrial IoT World.”
- Dr. Mark Maybury, Vice President and Chief Security Officer, Director, NIST National Cybersecurity FFRDC, The MITRE Corporation
DYNAMIC DISCOVERY
DDS provides Dynamic Discovery of publishers and subscribers. Dynamic Discovery makes your DDS applications extensible. This means the application does not have to know or configure the endpoints for communications because they are automatically discovered by DDS. This can be completed at runtime and not necessarily at design or compile time, enabling real“ plug-and-play” for DDS applications.
This dynamic discovery goes even further than discovering endpoints. DDS will discover if the endpoint is publishing data, subscribing to data, or both. It will discover the type of data being published or subscribed to. It will also discover the publisher’ s offered communication characteristics and the subscriber’ s requested communications characteristics. All of these attributes are taken into consideration during the dynamic discovery and matching of DDS participants.
DDS participants can be on the same machine or across a network: the application uses the same DDS API for communications. Because there is no need to know or configure IP addresses, or take into account the differences in machine architectures, adding an additional communication participant on any operating system or hardware platform becomes an easy, almost trivial, task.
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