UBF and asynchronous communication

[Edmund Dengler]

Hi all!

In reviewing the UBF items from Joe's website, it looks like the entire
system is premised mostly on the basis of synchronous communication, with
a server being the only component that can send asynchronously. Basically,
it appears that UBF cannot talk about concurrent communication events (or
essentially, substates) or asynchronous sends. This has a couple of items
that impact usage from my end:

(1) We do some of our work over satellite, and with one-way trip times of
1 second to 4 seconds, having a communication synchronize on a response
would generate significant throughput slowdown.

Is there the equivalent of: "type() -> EVENT", similar to "EVENT ->
type()" for server initiated messages. Basically, messages that do not
need to wait for a response.  Possibly "type() -> state"?

(2) If the above is feasible, has any thought been given to supporting
concurrent operations? There are two approaches to this off the top of my
head: (a) the use of multiple "channels" where each channel would
implement the synchronous communication, or (b) the idea of concurrent
states where replies can actually impact state rather than the NULL
operator of EVENT.

Regards!
Ed