Two Example Web Applications

Scaling WebObjects
Example Apps
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Summary
Postscript

Our example applications allow us to make certain assumptions about what we will need to support , and how much money we can spend supporting those applications. There are no hard and fast rules for dealing with web applications, each one is different. But by showing two different applications, you can see how each one has different needs, which leads to a different upgrade path.

Nile.com: Nile.com is a web-commerce application. That is, its a a web storefront like amazon.com. In fact, lets say we're trying to build a clone of Amazon.com.

Going to the amazon.com front page, we can determine the following things: The front page uses 29K according to Navigator. (Tip: Use page Info to determine the size of any page, and the size of its components). So we'll use that as an average page size for the HTML. But lets not forget the images! The front page has images totaling another 40K. If I bring up a book page, I get a 30K HTML page and 12K of new images. (Images are reused from page to page. )

So lets make some assumptions here. Lets say an average user will look at 10 pages before making a purchase. That's 300K for the pages, 40K for the front page images, and 12K per page in new images. Grand total is 448K for 10 pages, or about 45K a page. Just for fun we'll say that the profit on each purchase is $5, but we only make sales for 8 hours/day on weekdays.

For illustration purposes, I'm going to take the time it took to engineer the original Dell online store (6 weeks), and double it. Since the original store took 6 man-weeks, doubled is a total of 3 man-months to implement nile.com. Lets say $150/hour for a web application consultant, or $72,000 worth of engineering.

Lets say that there are 10 database transactions per page. That is, each page has 10 items that are pulled from the database.

Yippee.com: Yippee.com is some sort of web "information application" for a corporation. In this case, lets say we want to build a clone of Yahoo. Going to their front page, we find that it weighs in at 9K with 8K of images. One level down is 9K, with only an ad as a new image, which we'll ignore since this is supposed to be an internal corporate application. If we assume that Yahoo will serve 5 pages on average to a user, then Our grand total is 53K or about 10K a page.

For illustration purposes, I'm going to say one man month of engineering at the above rate or $24,000 worth of engineering.

I have no idea what the real number should be, but lets say that there are 25 database transactions per page. That is, each page has 25 items that are pulled from the database. Unlike nile.com where we have a profit motive, lets say every 25 pages/day is one user using the program for one day. Our corporate masters want to know the cost per user/per month if users only use the program during business hours. We'll spread any hardware or software purchases across each month by charging 1/10 of the cost to that month's bill.

Ok, we've just built our applications, lets deploy!

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