Every spring, Monster.com, one of the largest job sites in the United States with an average of more than 3 million visitors per month, experiences a large increase in traffic.

Aaron Braham, vice president of operations, attributes the spike to college students who increase their job-search activities as they approach graduation.

Monster.com uses a three-tier client–server architecture that has 150 Web servers and 30 databaase servers in its main site in Indianapolis. It plans to move that to 400 in 2001 by gradually growing the main site and adding a new site with servers in Maynard, Massachusetts, just in time for the spring rush. The main Web site has a set of load-balancing devices that forward Web requests to the different servers, depending on how busy they are.

Braham says the major challenge is that 90 percent of the traffic is not simple requests for Web pages but, rather, search requests (e.g., network jobs available in New Mexico), which require more processing and access to the database servers. Monster.com has more than 350,000 job postings and more than 3 million résumé on file, spread across its database servers. Several copies of each posting and résumé are kept on several database servers to improve access speed and provide redundancy in case a server crashes, so just keeping the database servers in sync so that they contain correct data is a challenge.

Questions

1. What are the two or three primary nonfunctional requirements that have influenced Monster.com’s application architecture?

2. What alternatives do you think Monster.com considered?