4. Compress and Encrypt in the Right Place

Often times host machines compress information prior to transmission. This is meant to improve bandwidth utilization in a virtual environment. However, compression obfuscates visibility into the actual data, which makes it difficult for downstream WAN optimization devices to provide their full value. Therefore, it may be a better choice to turn off compression functionality in the virtual host (if possible), and instead enable it in the WAN optimization device.

Moving compression into the WAN optimization device has another added benefit: it frees up CPU cycles within the host machine. This can lead to better performance and scalability throughout a virtual environment.

IT staff should also consider where encryption takes place in a virtual infrastructure, since encryption also consumes CPU cycles in the host.

5. Go With the Flows

Network scalability can have an important impact on the performance of virtual applications and VDI. The average thin client machine has 10 to15 TCP flows open at any given time. If thousands of clients are accessing host machines in the same centralized facility, that location must be equipped to handle tens of thousands of simultaneous sessions.

When it comes to supporting large numbers of flows, there are two "best practice" recommendations. First, as discussed above, it is recommended that compression and encryption be moved off the host machine to free up CPU cycles. Second, make sure your WAN acceleration device supports the right amount of flows for your environment. The last thing you want to do is create an artificial bottleneck within the very devices deployed to remove your WAN's bottlenecks.

© 2009 CXO Media Inc.