The cloud forecast for WAN optimization - more than just ADCs

Ann Bednarz recently wrote a Network World piece where she discusses the need for WAN optimization in the rapidly growing cloud computing environment.  The focus of the article was on F5 and how their Big-IP application delivery product is geared towards the enterprise cloud computing market as opposed to the public cloud services like Amazon and S3.  

F5's Big-IP product is an asymmetrical solution with a single appliance residing at the datacenter.  The F5 appliance offloads SSL servers that are bombarded with requests from SSL-encrypted cloud-based applications in addition to providing caching and pre-fetching of web-based cloud applications.  Gartner notes that application delivery controllers can provide data center efficiencies of 20% to 50%.

Reading this article reminds me that there is still much to do with regards to educating the market about the different types of WAN optimization technologies that are available.  While the focus of this article is on single box application delivery controllers (ADC) that reside at the data center, it is important to understand that symmetrical solutions like Riverbed where you have an appliance on both sides of the network or a piece of software at one side and an appliance on the other side, play an important role in enterprise cloud computing apps as well.

I first want to qualify my intentions up front.  I am not bashing or disbarraging asymmetrical application delivery products from the likes of F5 and in fact, I believe ADCs are complementary to a symmetrical WAN optimization solution like what Riverbed provides.  How are they complimentary?  It is very common to have an F5 box at the data center handling the offload of the heavy resource intensive crypto processing that the server environment would otherwise have to deal with.  By offloading the servers, the servers can deliver content to more users and by not being bogged down, response times can improve.

With the server-side processing performance bottlenecks addressed, what about the WAN-side bottlenecks that exist with limited bandwidth, but more importanltly the impact that high latency has on the response time of web-based enterprise cloud applications?  Performing compression on a single-ended device has a limited impact on the WAN traffic.  This is where Riverbed comes into play.  Riverbed's Steelhead appliance and Steelhead Mobile software are positioned at both ends of the WAN link.  Both work together to safely decrypt the SSL encrypted stream and apply highly effective data-deduplication algorithms to the encrypted traffic.  The result is often between 60% to 95% of the traffic is reduced from the WAN.  In addition to reducing the data payload for web-based apps, the Riverbed dual-ended solution also applies two levels of protocol optimizations to improve client-side performance at both the TCP layer and application layer.  The result for many web-based applications is not just 50% faster performance, but in many cases 300%, 500%, or even greater. 

The point is don't focus solely on application delivery controllers when tackling web-based application performance within your enterprise cloud environment.  Symmetrical WAN optimization solutions like Riverbed can also play a critical role in improving performance.

I would love to hear from you if you have both ADCs and symmetrical WAN optimization devices in your envrionment. 

Comments

[Dan Campbell]

Your comments are correct. Some of it is with the term "WAN optimization" taking on broader and more convulated meaning, somewhat because the vendors in various "upper layer optimizaiton" areas play in the arena but have other features. Historically, F5 was into server and global load balancing, SSL optimization, etc. More recently it has gotten into the true WAN optimization side of it like Riverbed where you are trying to speed up the performance of an application over a link that has latency, and/or reduce the traffic on the (perhaps low speed and/or congested) link. Those two latter benefits have little to do with server load balancing or SSL optimization (but of course those are also great, necessary features.)