3-tier with message server is an improved version of 3-tier TP monitor serving the same funnelling processes. However a message server connects with data sources instead of RDBMS as TP monitor. A message can be considered as a self contained object containing header and body of the message. The header includes the priority, addresses and ID number for directing the message reaching the server from the client and vice verse. The body part contains text, images information for processing by the server.
The prime difference and advantage of message server over TP monitor is that message server’s architecture is designed around the intelligence in the message whereas the TP monitor’s architecture intelligence is at the TP monitor or in the process logic of the application server. In some situation, message server acts as a router for routing the messages only. Message server is communication related and therefore would be more flexible and potable to different environment and networks than TP monitor(Schussel, 1995).
Configuration of Message based client/server is as below:
Reference
Schussel, G. (1995). Client/Server:Past, present and future. Retrieved March 9, 2008 from http://www.dciexpo.com/geos/dbsejava.htm
