Usage scenarios and examples

[Carl Wolff]

If you know an usage example/scenario, please post it here, we can use this info by defining the API.

[Jaap Crezee]

Scenario:

All computers in the office network have temperature, processorfan-speed sensors and/or voltage sensors. These sensors could be read out by corresponding SQLBusRt supplier processes and put onto the SQLBusRt bus. There can be several SQLBusRt subscriber processes which subscribe to the supplied  data using SQL queries. Example:

PC1: temperature, cputemperature, cpufanspeed, 12v, 5v
PC2: cpufanspeed, casefanspeed, 12v, 5v
PC3: temperature, 12v, 5v

all publish to the SQLBusRt manager...

Subscriber1:

SELECT * FROM temperature WHERE sensorid BETWEEN PC1 AND PC2 DEADLINE 1, 3 ORDER BY timestamp DESC LIMIT 1, 15

Result: every 1 second min and 3 seconds max (timeout...) give from PC1 & PC2 the last 15 sensor readings...

Subscriber2:

SELECT * FROM cpufanspeed WHERE sensorid IS PC2 DEADLINE 2, 10 ORDER BY timestamp DESC LIMIT 1, 5

Result: every 2 seconds min and 10 seconds max give from PC2 the last 5 cpufanspeed sensor readings....

[Bram Smulders]

Stock trading

Multiple publishers supply stock value information to the bus. This information is stored in the database.
Stock traders can do a request to monitor the stock values they are interested in. Not only the current, but also history data should be available, so they can analyze this data to make predictions, and to create graphs.

[Bram Smulders]

Pushing information on mobile devices

Many people have mobile phones. It would be interesting to send them news or facts specific to a certain location.

Imagine that with the signal strength between a mobile phone and different gsm antenna's we predict the mobile phone's position.

We have information suppliers who post information specific to a certain location (or area, it does not necessarily have to be a point).

Whenever a mobile phone is predicted to be close to a location or in a certain area for which information is available, this information can be pushed onto the mobile (for instance with an sms).

[Bram Smulders]

Video streams

A supermarket has multiple surveillance camera's.

a security guard monitors the images from these camera's. When the need exists to monitor some images in the past, the security guard can request these images.

Also, it is possible to view the stream with a fixed delay. For instance, we can continuesly view the images as they were taped 5 minutes ago.