Symmetric Optimization in the Cloud

Cloud computing has opened new avenues for application deployment that allow a savvy IT manager with experienced staff to place applications in the location that makes the most sense for the application. Architects can choose between a primary data center deployment, or cloud deployment to suit the needs of the application in question.

But there is still a lot about cloud that is… cloudy, and this causes some issues when deploying applications wholly or partially to a cloud environment. If the cloud in question is a public cloud, there are a variety of issues to consider, from firewalling the applications to secure connections back to the datacenter. Most of these are eliminated if your cloud is private, simply because it can sit behind your firewall and will have a secure connection – secured on both ends.

There are some issues, however, that will persist when making a cloud deployment. One of them is an increased usage of your Wide Area Network (WAN) connection. Whether you are going to a private cloud in a remote data center or a public cloud in someone else’s data center, all communications with applications will have to flow through your WAN.

The WAN connection is slower and more prone to packet loss and latency, and data transferred over it needs to be protected from man-in-the-middle attacks. These are issues that all WAN communications have faced, almost since the inception of Wide Area Networking, and companies created solutions to minimize the risks. WAN optimization is the broad name attached to these solutions. By putting a specially designed system at each end of a connection, packets on the way out can undergo compression, TCP optimization, de-duplication, and encryption,; and at the destination, all of these things can be unwound, resulting in the same exact thing coming out that went in. The improvements for WAN connections can be truly astounding, depending upon the quality of the connection and the traffic being sent through it.

In the case of WAN optimizations, de-duplication on-the-wire is used for larger chunks of repeating data, while compression is used for what is left. TCP optimizations attempt to mitigate latency and packet loss by imposing rules about things like retries that are part of the TCP standard. Taken together they are a powerful set of optimization tools that can speed communications over the WAN many times over.

Not in the Cloud You Don’t!

But cloud environments do not generally offer WAN optimization, and even if you find one that does, WAN optimization techniques and procedures are unique to vendors – meaning the cloud provider would have to use the same WAN optimization gear as your organization uses. That’s unlikely, and again, it is also highly unlikely you would find a cloud provider that even offered access to WAN optimization hardware unless you negotiated for it at contracting time.

And this situation has created an environment where stand-alone applications that do not need access to the data center in any way are the only ones considered suitable for cloud deployment – particularly in public cloud scenarios.

But there are many applications that could make use of the cloud for reasons of traffic patterns or volume requirements, but need access to internal data center resources. In fact, it could be argued that the truly independent application is a rare beast in the modern data center, and even if one is deployed, it will eventually need integration into the core data center for reporting or security or accounting purposes. This is one of the things that keeps the number of applications actually deployed to the cloud for production use low, though the potential is very high.