Enterprise Resource Planning is a very popular class of enterprise applications represented by such companies as Oracle, Peoplesoft, Baan and SAP. The software is comprised of various modules for managing different company departments while integrating them as well. The current application model is described as a three tiered design that describes the flow of traffic between client and servers. The application is comprised of a client software module, an application server module and a database server module. The three tiered model has the application and database modules residing on different server machines.
There is significant performance improvement with the three tiered model since all application and database transactions can be co-located at a high speed Data Center with Gigabit campus switches. The client software is engineered to send an efficient smaller request, which is 2-3 Kbytes across a WAN link to an application server. The application server processes that request by sending a specific query to the database server, which will be on the same campus segment. The database finds the database record and returns that to the application server. The application server then sends an SQL reply with that information to the client across the WAN.
This model was designed for the most effective utilization of circuit bandwidth, which has the most affect on company costs and application performance. As well, co-locating the application and database servers on the same campus segment and on different machines allows for scalability and performance. The campus Gigabit links at the Data Center are at least 10x faster than the WAN circuits. That and splitting the application and database modules allow for scalable databases and higher performance application servers. With both modules running on one server there would be an upper limit at which those modules would have to be separated. Future developments with ERP applications will focus on making a client software module that requires even less bandwidth than the current 3 Kbytes for a faster response time and cost effective bandwidth usage.
Shaun Hummel is author of Network Planning and Design Guide available at amazon.com and CiscoDesignBooks.com featuring Networking Books, eBooks, Certifications, Articles and Design Tools.