[evla-sw-discuss] alerts - reliable delivery

[Boyd Waters]

> Anyone know of a nice, thin layer or set of libraries that could be 
> used
> as the publish-subscribe mechanism between the antenna objects and the
> interested parties, such as flagger ?  Maybe something like ACE 
> toolkit/
> framework, only for Java rather than C & C++ ?
>


Why do we need an additional layer between antenna and flagger? 
Particularly if this particular issue will force the adoption of 
message-oriented middleware -- why not have the point-to-point of 
alerts go to the flagger box?

I have a straw-man diagram which shows a role called "Array Monitor", 
which received directed communications from the array. The services 
running on that box are Database Dumper, Flagger, and Checker.

This sounds like Ken's "layer whose job is to catch all monitor point 
values and alerts and then make this information globally available."

(My toy diagram also shows an "Antenna server" for control purposes.)