DDS™ - The Proven Data Connectivity Standard for IoT™ Nov. 2016 - Page 8

HOW DOES DDS WORK? How Does DDS Work? HIGH LEVEL DATA-CENTRIC INTERFACES REPLACE MESSAGE-CENTRIC PROGRAMMING The main goal of DDS is to share the right data at the right place at the right time, even between timedecoupled publishers and consumers. DDS implements global data space by carefully replicating relevant portions of the logically shared dataspace. THE RIGHT DATA Not all data needs to be everywhere. Middleware should only deliver the data that consumers really need. Interest-based filtering can apply to both content and data rates. With proper implementation, DDS saves bandwidth and processing power, and minimizes overall application complexity. As a data-centric solution, DDS can understand the schema of the shared data. This allows it to filter on content, age and/or lifecycle to provide applications with only the data they need. For example, you can send only boiler temperatures over 300 (content filter) with at most ten updates per second (rate). This efficient approach can often save 90% of the data communications overhead in many systems. THE RIGHT PLACE Data must be available where it is needed, to facilitate self-forming systems. DDS distributes and maintains data so it is readily available. DDS dynamically discovers publishers and subscribers, the data types they want to share, and the related Quality-of-Service (QoS). Following a successful match, DDS enforces timely distribution according to the QoS. It implements a QoS-enforced logical channel for each data stream between each publishersubscriber pair. A DDS subscriber can be sure that its peer publisher is actually alive and that any data produced will be delivered. This greatly simplifies application development and error handling. THE RIGHT TIME Real-time systems interact with the real world. Data must be available on timeβ€”the right data too late is a failure. Data differ in priority, reliability, timing, an ½Ρ‘•ΘΉ½Έ΅™ΥΉΡ₯½Ή…°ΑΙ½Α•ΙΡ₯•ΜΈL‰…±…Ή•ΜΥΡ₯±₯ι…Ρ₯½Έ½˜Ν…ɍ”Ι•Ν½Υɍ•ΜΡΌ‘₯ΝΡΙ₯‰ΥΡ”‘…Ρ„…Ёё”Ι₯‘ЁΡ₯΅”Έ)L΅₯‘‘±•έ…Ι”Ύ͕±½₯…°E½LΑ½±₯₯•Μ°…͕́Ё‰δΡ‘”…ΑΑ±₯…Ρ₯½ΉΜ…ЁΙΥΉΡ₯΅”°ΡΌ‰…±…Ή”•™™₯₯•Ήδ…Ή)‘•Ρ•Ι΅₯Ή₯Ν΄ΈQ‘”E½L½ΉΡΙ…Ρ́•ΉΝΥΙ”Ρ‘•Ν”Ρ₯΅₯ΉœΙ•±…Ρ₯½ΉΝ‘₯ΑΜΈ½Θ•α…΅Α±”°₯˜„ΝՉ͍Ι₯‰•ΘΙ•ΕΥ₯Ι•Μ)…ΈΥΑ‘…Ρ”•Ω•Ιδ€ΔΑ΅Μ…Ή₯Ρ́΅…э‘•ΑΥ‰±₯Ν‘•Θ‘½•ΜΉ½Π‘•±₯Ω•Θ°Ρ‘”ΝεΝΡ•΄‘•±…ɕ́…Έ•ΙΙ½Θ°•Ή…‰±₯Ήœ)Ι•΅•‘₯…°…Ρ₯½ΈΈE½LΑ½±₯₯•Μ½Ω•Θ΅…Ήδ‘…Ι…Ρ•Ι₯ΝΡ₯Μ°₯Ή±Υ‘₯ΉœΥɝ•Ήδ°₯΅Α½ΙΡ…Ή”°Ι•±₯…‰₯±₯Ρ䰁Α•ΙΝ₯ΝΡ•Ή”°…Ή±₯Ω•±₯Ή•ΝΜΈ((ΰ((0