EAI — extensions

3) Most of the extensions are transformation service "patterns", such as filter, aggregator, etc., yet some are messaging service "patterns" such as pub/sub, topic, etc. I like the idea that they can be stereotyped, but they are not associated to the traditional middleware services stack that we have been using for a while. I could get real detailed (e.g., aggregator should have a sort or orderby operation, etc.) but I am swamped at the time