XML Acceleration Using Virtual Appliances

I have never met Gordon Moore. But his law? Well, Moore’s Law is my best friend. My entire career, it helped to make my work run faster. On more than one occasion, I think it may have saved my job. I like Moore’s Law a lot.

Moore’s Law has had a big impact on XML acceleration. XML processing—specifically schema validation, XSLT transform and XPath query—is one of those problems that lends itself well to acceleration using specialized silicon. Tarari (now a part of LSI) is the leader in developing specialized chip sets for accelerating basic XML functions. We’ve leveraged their technology for years here at Layer 7 for our hardware appliance line, and we will continue to do so in the future. But like all specialized chip designers, Tarari’s engineers are engaged in a protracted battle with the ever-increasing capacity of general-purpose processors. Dr. Moore’s Law pursues them with a relentless pace, driving Tarari toward the breakthroughs that leave general CPUs far behind each time these begin to nip at their heels.

Silicon, however, is not the only approach to accelerating XML. Tremendous gains in XML processing can also be realized using highly optimized, pure-software algorithms that run on generic CPUs. These, of course, effortlessly ride the wave of Moore’s law. We use such algorithms at Layer 7 to provide very real XML acceleration in our virtual appliances, which obviously have no access to dedicated acceleration boards.

This fact that virtual appliances can accelerate XML processing is often missed. I was reminded of this when reading Joe McKendrick’s latest blog entry  The Case for Considering XML Appliances. Joe’s entry builds off a recent piece published by Thomas Rischbeck from IPT concerning SOA intermediaries (I’m particularly fond of the last diagram in Thomas’ article). As with all of Joe’s work, his article today is very perceptive, but I disagree with one statement he makes:

And, as is the case with appliances these days, they also come in virtual form as well. The only catch is that virtual XML appliances cannot provide XML acceleration.

I see XML acceleration as a continuum like this:

Virtual appliances may not be as fast as hardware appliances for XML acceleration, but they do accelerate processing over conventional approaches. And one of value propositions of virtual appliances is that these provide a simple means to scale horizontally (in clouds, or in conventional virtualization farms) instead of vertically. Moore’s Law is its friend too.

Layer 7 Technologies is the only SOA Gateway vendor that offers a product line that features both hardware and virtual appliances. You can buy the hardware SecureSpan Gateway appliance that includes silicon for XML acceleration. Or you can buy the virtualized SecureSpan Gateway appliance that includes our highly tuned algorithms for XML acceleration. These products offer identical functionality—so choose the one that makes the most sense in your architecture.

And don’t ever let a form factor dictate your architecture.