Challenges
Reliability means that the user always receives complete information of the highest possible timeliness. Incomplete information has to be detected and, if possible, must be requested again. Otherwise the application or user has to be notified about the transmission failure. In
less critical situations it might be possible to reuse information from previous transmissions.The second important factor is the
performance of the system. Beside the application, the response time of the system depends on the bandwidth of the communication
channel. Hence low transmission rates make it difficult to deliver e.g. complex maps within a short time. The data management has to guarantee the efficient usage of the communication channels. Moreover, the response time of the system should be largely independent of the number of communication partners in the system.
Furthermore the data structures used for data exchange must be flexible in different ways. Sensors can provide their data in proprietary formats. Hence they have to be transformed at some point to the standard data structure. This can be done at the receiving device or, if the device is not able to do this, the data has to be encapsulated into
a standard message and transformed at some other point. In addition, the compatibility of different versions of data schemas has to be handled. Data schemas can change over time if new versions of an application are developed, but it is important that devices with different application versions be still able to communicate.