Basic HTML version of Foils prepared September 13 1998
Foil 22 Exploiting Multi-Tier Commodity Software Model
From Computing on the Pragmatic Object Web EuroPar Invited Presentation -- September 4 1998. byGeoffrey C. Fox
Essential idea is consider a three tier model
Top tier is the client (in "Network Computer" based 4 tier architectures this becomes 2 tiers)
Second tier are servers coordinated by commodity technologies such as the Web and CORBA and communicating via HTTP(Web), IIOP(CORBA), RMI or custom Java sockets.
Use middle tier component/container model -- Enterprise Javabeans
Third tier are services such as databases, MPP's
Preserve the first two tiers as a high functionality commodity information processing system and confine HPCC to the third (lowest) tier.
MPI becomes the high performance "machine code" for message passing which you use if HTTP, IIOP or RMI have insufficient performance
