Another test added specifically for this review was a UDP video stream. To highlight the NX-5500's UDP and QoS capabilities, I set up a video stream using the open source VideoLAN software package. On the first pass, the video played correctly on my client PC and I saw a modest reduction in traffic on the WAN. Repeat plays of the same video showed a tremendous decrease in the amount of traffic on the WAN, owing its performance increase to Network Memory. The chunks stored in the cache are encrypted using hardware-based AES-128 (Advanced Encryption Standard) and are available across all data flows and applications, regardless of direction or session.

The Bottom Line Silver Peak NX-5500 2.0 Silver Peak, silver-peak.com Excellent  8.9 criteria score weight Performance 9 40% Traffic Management 9 25% Reporting 8 15% Setup 9 10% Value 9 10% Cost: $44,995 per appliance; all features enabled at listed cost. Platforms: Any Ethernet network running TCP and UDP traffic Bottom Line: Silver Peak's NX-5500 provides some of the best performance increases tested to date with a wide range of supported applications and protocols. Its ability to both optimize and cache UDP traffic is a major plus for enterprises doing branch office-to-datacenter replication or video streaming. Setup and configuration are straightforward, and reporting and monitoring provide a good view into the overall health of the system. About our Reviews and Scoring Methodology

Click for larger view.

Setting up and configuring the appliance was more straightforward than in the previous release, requiring fewer steps to create my optimization policies and tunnel definitions. I liked that I could define different policies based on application, protocol, source and destination address, and DSCP (differentiated services code point) marking. I was able to choose the type of optimization to employ, such as TCP and CIFS accelerations, based on the policy, or to simply pass the traffic through without any optimization. This granularity allowed me to define one policy for my Double-Take replication system and one for scripted tests on another PC.

The reporting engine in the NX-5500 provides a good all-around view of the health and efficiency of the optimized traffic. The graph of application stats details the amount of traffic on both WAN and LAN interfaces, total bytes on both, and also the overall reduction in traffic. The tunnel statistics show the amount of traffic between a pair of appliances, the overall latency, and reduction in traffic.

The historical graphs for applications and tunnels are very easy to read, but unfortunately only store one month of data. True historical reporting requires sending the collected information to another reporting engine for analysis, such as Netflow or a CSV (comma-separated value) file.

Now available with the Silver Peak appliance is a GMS (Global Management System) that allows for centralized administration and detailed reporting capabilities. GMS users can view detailed stats on application behavior, WAN performance, such as latency and loss, and bandwidth utilization. GMS is available on a stand-alone appliance and can handle as many as 500 NX appliances.

The NX-5500 is a smooth mix of application and protocol support, and its performance is, without question, one of the best I've ever tested. The TCP and UDP support is first rate, providing all traffic types excellent acceleration and optimization. The reporting engine provides enough day-in/day-out information to be useful, but to really see your WAN optimization over a long period of time requires an external reporting system. This one shortcoming aside, Silver Peak's NX-5500 should be on every network admin's short list for WAN acceleration and optimization.