Do you think cache is something only an ISP needs? Think again. As the Internet becomes more business-critical, cache vendors are anticipating that private companies and government will be their next—excuse the pun—cash cow.

What can cache offer you? Vendors claim cache can:

  • Deliver content within your company faster and more efficiently.
  • Increase the delivery of content to your customers.
  • Filter content.
  • Add a layer of security.

But with prices ranging from $3,000 to more than $100,000, plus the staff you may have to dedicate to your cache machine, is it worth it?

In many cases, you can expect an ROI within three to 12 months, experts say. But in some cases, you may have a difficult time justifying the expense.

Speeding content delivery inside your company
The most common use for cache is to speed up delivery of popular Internet content to your company. The process is also called forward proxy.

Cache technology hardware and software sits between your users and the Internet, retaining copies of images and content from high-volume sites. When users request the information, their request passes through the cache, which checks to see if it has a copy. If the cache has the information in its memory, it instantly checks to ensure it has an updated copy. If so, the user receives the information directly from the cache, reducing network traffic and download time.

Proxy servers are armed with a certain amount of cache, but you can also buy cache software or a cache-dedicated appliance to add extra caching power.

“Caching is a very proven way, a very quick way, of solving some fairly significant performance problems,” said Greg Govatos, director of marketing at CacheFlow, Inc., one of the major cache players. “Any business, if it has 50 employees and up, would benefit from caching.

“Where you’re going to get the most benefits is if you have distributed sites where you have expensive network connections to pay for at each of those sites.”

Forward proxy can also be justified in terms of ROI, according to Giga Information Group analyst Joel Yaffe, who has researched and written about Web caching and its implications for businesses.

“With a forward proxy, you get a monthly Internet usage bill and you see what it costs you,” Yaffe said. “And then you can say, ‘Well, if we can cut a certain percentage by investing this much money (for caching) one time, then we break even in six months or 12 months or whatever.’”

If your enterprise is located outside the United States, you can recoup the costs even more quickly, according to Duane Wessels, a cache researcher and developer with the IRCache, a University of California San Diego program funded by grants from the National Science Foundation.

Bandwidth is more expensive outside the U.S., and since most of the content is U.S.-based, a company in Europe or Australia will spend more than a U.S. company retrieving the same content, Wessels explained. That makes it easier to justify the costs of cache.

“A company in Australia puts in a cache and it pays for itself in probably two months,” said Wessels. “In the U.S., the payoff’s going to be longer. It might be six months or a year.”

Speeding content delivery to customers
Cache can also help speed content to online customers and prevent peak events from crashing your servers. This is referred to as reverse proxy or server-side caching.

The cache speeds delivery of content to your customers by monitoring which pages are frequently requested and holding those pages in memory. When a user asks for that content, it can be served up immediately rather than sent through the server. For dynamic content, the cache can still serve static elements, freeing up the server to process other requests.

“As Web sites get bigger and as the needs and traffic volumes grow more and more, we see customers deploying larger products so they can handle peak events,” Govatos said. “We handle peak events very, very gracefully.”

Server-side caching also provides an alternative to adding additional servers. You don’t have to be to benefit from cache, Govatos added. CacheFlow’s customers include a law firm in the Northwest with approximately five offices in the region.

The firm used caching in each office and was able to cost justify in three months, he said. Others have told him cache appliances allowed them to eliminate between five and 10 Web servers.

“That’s a huge advantage both for capital cost reasons and management cost reasons,” said Govatos. “That’s a huge, huge benefit, so we see an exploding amount of growth in this server-side caching space as Web sites become more business critical, and as they start selling their products online and participating in these business-to-business exchanges.”

But since software and hardware for Web servers really aren’t that expensive, it’s harder to justify the expense of reverse proxy, according to Yaffe, who researches cache.

“With a forward proxy, you get a monthly Internet usage bill, and so you see what it costs you,” Yaffe said. “With a reverse proxy cache, it’s much more difficult to determine what the costs of all the Web servers are because you don’t get a monthly bill for it, typically.”

Filtering and security
Cache can also include features that address two major corporate usage dilemmas: filtering and security.

A cache machine can be used to authenticate users, differentiate between users and screen out certain categories of content.

Universities frequently use cache to differentiate between professors and students, allowing professors to access content more quickly, according to Wessels.

“One of the most popular features for Web caches is filtering requests,” he said.

For example, one way that businesses might use filtering would be to keep employees off job-search sites, Govatos said.

Because cache machines use a customized operating system, cache can also provide another layer of network security. They are also being packaged with virus protection software.

Recently, CacheFlow introduced a cache appliance that can protect your server from denial of service attacks, Govatos said. The cache can determine whether a request is part of an attack and drop the requests out of the network, he explained. Predictably, this is proving to be a very attractive feature with executives.

“CTOs get rewarded when their sites perform like a champ, but they get fired when sites go down because of something like a DoS attack,” he said.

But do you need it?
There’s no question cache can improve your Internet performance—but how can you tell if you should invest in this technology?

“You know you need it if your proxy server software isn’t able to keep up with your demand or you’re having to throw in an inordinate amount of infrastructure servers and proxy power to solving that problem,” Yaffe said. “Is there a ratio I can offer? No.”

Giga predicts that most companies will receive their cache services from ISPs and other hosts, who will package cache as an added value.

For example, Yaffe said data centers plan to offer reverse proxy caching as an added service to protect against peak events.

Cache also will require maintenance, Wessels cautioned.

“It’s not the kind of thing you just put it there and it works,” he said.

The bottom line: It’s still unclear whether cache will become a WAN staple. You should evaluate cache’s ROI to determine if it’s worthwhile for your company.

“As with any new technology, it takes a little bit of time to figure out how to best leverage it,” Yaffe said. “The jury is still out.”
We’re curious: Do you have a machine dedicated to cache? What do you—or would you—use it for? Let us know if you think cache is worthwhile by e-mailing us or posting a response below.