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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