The first surprise you will get after you consolidate your branch office servers in the data center is that application performance over the WAN falls off and user productivity suffers. To fix this you deploy WAN Optimization Controllers (WOCs) so your applications go much faster and you recover bandwidth that was lost to redundant traffic. After the WOC’s are installed a strange thing happens to your performance reports. Application response appears to be instantaneous. It’s as if the distance between your data center and your branch office shrunk to nothing. We know that you can’t overcome the speed of light and there will always be some latency on WAN links. So what happened?
What happened is that the WOC distortion effect has come in to play. WOCs proxy TCP at each end and send acknowledgments immediately. As result performance monitoring systems lose visibility to the actual round-trip time. WOC distortion poses a challenge to getting accurate end-to-end performance analysis. To understand how your applications are performing you need to know the average response time between client and server, the Network round trip time to move data from one node to another as well as the server’s response time to a request and the data rate that was achieved.
To get accurate performance reporting you need a solution that overcomes the effect of the TCP proxy and can report on actual end-to-end application response time. Having access to accurate reporting will allow you to measure the benefits of a WOC deployment and to evaluate the expected performance improvements of WAN Optimization and identify locations that will benefit most from a WOC installation. Over the longer term an accurate reporting solution can be used to baseline the improvements in application performance and act as an aid in application, server and network tuning. Cisco has been working with a number of network management vendors including Fluke, Infovista and NetQos to provide management reporting. Read this paper to learn how Cisco and NetQoS are delivering Accurate End-To-End Performance Management Using NetQoS SuperAgent and Cisco Wide Area Application Services