you create a Java webservice and a Flex client.
The client requests data from the webservice. All receieved data is
permanently stored in the client cache. The client then regularly
requests updates from the webservice. When an update is requested
only the updated or newly added data are sent.
See the attachment for detailed functional and non-functional
When bidding please provide some references and a very basic
concept for your solution, so we can rate your design.