How caching works: the concept

Assume you are working on a Soap Opera Daily channel that consists of 25 individual pages, each of which are updated every day at midnight. It is a very popular channel, and you have also got a subscriber base of half a million people. Your customers, wanting to get the latest Soap Opera news every day, are updating their channels daily like clockwork.

Here is what happens if you do not have your channel set up for caching:

Step 1: Every day, half a million people ask your M-Business Sync Server for updates to your channel.

Channel users synchronize without caching

Step 2: Your M-Business Sync Server hits your home page, grabbing 25 individual pages half a million times a day, meaning your server is dishing out 12.5 million pages a day just to your M-Business Sync Server.

M-Business Sync Server hits Web server for each page request

Step 3: The M-Business Sync Server compresses these files and uploads them to the users' Palm OS or Microsoft OS device.

M-Business Sync Server downloads compressed pages to users

This is a pretty slow process. Your server is probably struggling under the weight of dishing out 12.5 million pages a day just for your M-Business channel. Worse, your readers are waiting a long time for their channels to synchronize because your M-Business Sync Server first has to get the pages from your overworked server, compress them for better viewing on M-Business Client, and then upload them to their mobile device.

This is what happens if you do set up your page for caching:

Step 1: You specify that all the pages on your channel are good for, say, 24 hours.

Step 2: Each day, the first time a user asks to update the channel, your M-Business Sync Server hits your home page, grabbing 25 individual pages. It compresses them, and uploads them to the user's M-Business Client.

M-Business Sync Server hits Web server for pages once a day

Step 3: The M-Business Sync Server holds on to those pages (already compressed) for future use.

M-Business Sync Server caches channel compressed pages

Step 4: The remaining 499,999 times a user asks to update the channel, the M-Business Sync Server simply sends off the precompressed, preloaded channel pages to users' Palm OS or Microsoft OS devices.

Note

This is an oversimplification. The M-Business Sync Server caches different versions of the compressed page depending on the M-Business Client device type (Palm OS vs. Microsoft OS). So it is not actually a savings of 500,000 to 1. It is more like a savings of 500,000 to 60. Which is still pretty good.

M-Business Sync Server sends cached pages to channel users

Your server is happy because its only working to push out 25 pages a day instead of 12.5 million. Your users are happy because they can get pages directly from the M-Business Sync Server instead of having to wait for that server to retrieve them from your Web server and then compress them.