Abstract

A broadcast data distribution system collects, edits, verifies, formats and distributes real-time (dynamic) and non-real-time (static) data.A central database is maintained and updated continuously. Data in the central database is continuously broadcast to an unlimited number of subscribers, each having receiving apparatus and a local database. In normal data traffic situations, real-time data messages are broadcast as they are received. In heavier data volume situations, newly received data messages are compared with last-known values for the particular data record being updated. If the change is determined to be significant, the update message is broadcast; otherwise, it is not. In extremely heavy data traffic volume situations, real-time data messages are not broadcast.The invention ensures that the subscribers' local databases are current, even when real-time data messages are not being generated, or are only being generated for data records whose values have changed significantly.Static (non-real-time) data messages are interleaved with real-time data messages to provide subscribers with a variety of different types of information.Subscriber access to broadcast data messages may be controlled by broadcast entitlement messages or message headers which enable or disable a particular subscriber's receiving apparatus. Once messages are properly received, the subscriber's local database is updated with the data contained in those broadcast messages.

Other References

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