Exclusive: WAN optimization, the Cisco WAE
Cisco unwraps an impressive array of appliances for boosting WAN performance
WAE applies two caching techniques to TCP traffic to reduce response time and improve overall performance. First, as does the Steelhead, Cisco WAE caches both files and chunks of data on a local disk, with the file cache doubling as a local read-only file store when the WAN link fails. Additionally, Cisco’s DRE (Data Redundancy Elimination) caches byte segments — again, as does Riverbed’s solution — reducing redundant traffic on the WAN by serving the segments from the local appliance’s cache.
There is one major difference between each vendor’s byte segment caches. DRE segments in WAE are not shared among the various connected appliances. In other words, each byte segment cache is specific to the appliance pair that the traffic passed through. Riverbed doesn’t have this limitation and makes all cached segments available to any Steelhead pair. Riverbed’s larger pool of byte segments allows for a greater “first pass” match, which can help reduce traffic on first-time data.
Cisco’s application traffic policy engine is the smarts behind the scenes, determining how WAE will optimize a specific traffic type.
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A unique service to WAE is its print server capability, allowing IT to use the appliance as a centralized source for printer support by directly loading it with printer drivers. This is particularly useful for branch offices, where many WAEs will be placed, eliminating local file servers.
Report what you sow
WAE’s reporting engine is one of the best I’ve seen out of all the WAN optimization appliances I’ve reviewed. I was able to view traffic statistics based on many different criteria such as optimized vs. pass-through and reduction. I could also drill down into specific applications such as e-mail, messaging, and Web while choosing the traffic flow direction — inbound, outbound, and bi-directional. Consolidated reports are available when using a WAE as the central management point for appliances across the WAN.
It has been a long time in coming, but Cisco’s entry in to WAN optimization is a very solid effort that doesn’t leave any major feature out. It may not be the fastest appliance I’ve tested, but it is a very close runner-up and provides great overall performance improvement in all traffic situations. Reporting is well done, and setup is straightforward with little out-of-the-box tweaking necessary. If you have Cisco gear already in place, make sure you check out WAE.