I'm creating a remote adapter in java and confused by the UD3 message.

It seems to me that it requires the java program to remember all the unique ID's that have been sent to it so that the program can append it to the ud3 message correctly. To me, it's not very scalable when millions of users connecting at the same time.

I'm not sure if I'm missing something but is there a way to broadcast all the change to all the user who are currently subscribing to a particular item without knowing their original request id. Any help is greatly appreciated