CIOIN

A cache by any other name... is still a cache.

Whether they're referred to as Wide Area File Systems (WAFS), Web caches, or Web application accelerators, the fact of the matter is that caches take a myopic view to an important enterprise challenge.

That challenge is to end the tug-of-war in which IT managers are stuck in the middle. On one hand, distributed employees need full, fast application access. But on the other, management wants to consolidate IT infrastructure in order to reduce expenses and meet regulatory compliance. How can an organization balance these needs? This challenge spans almost all applications that organizations use, from common end-user applications such as MS Office, file sharing and document management down to less visible administrative applications such as backup and replication, software distribution, and database synchronization.

Caching vendors claim that they solve these problems in one, easy-to-use device. They claim that their devices enable enterprise application acceleration, branch office IT consolidation, and bandwidth savings as well.

Caching, in fact, is a poorly architected, partial solution to enterprise application acceleration that may introduce more problems than benefits into a network. Caching devices, as we will explore in detail, seemingly improve throughput by short-circuiting the communication processes of applications and serving content locally. But this approach is limited in its efficacy, error-prone, and hard to manage.
This paper illuminates the 5 most dangerous shortcomings in the caching approach to enterprise application acceleration.

• Lack of breadth for application support
• Inability to handle common changes to information
• Data integrity weakness
• Inability to support disaster recovery
• Failure to really consolidate servers

Finally, this paper will present the Riverbed Steelhead appliance as an alternative to caches. By first understanding the shortcomings of caching, it will be easy to see why the Steelhead appliance is a more intelligent approach to meeting the application acceleration challenge. By the end of this paper, it will be easy to see how Steelhead appliances encompass the limited benefits of caching, but also give an enterprise much more acceleration power, breadth, flexibility, and manageability.

Read on to understand the ugly truths behind caching products and the troubles they can bring to your network. If you'd like to hear the real story behind caching, watch caching vendors squirm as they have to admit to these 5 deal-breaking limitations:
Ugly Truth #1: "You're likely to need multiple caches in each of your offices."
Ugly Truth #2: "If users make changes to files, caches are not very useful."
Ugly Truth #3: "Caches can interfere with basic data coherency."
Ugly Truth #4: "Caches can't accelerate backup and replication."
Ugly Truth #5: "It takes a lot of work to implement and maintain a cache."