XML can be a bit of a power-eater – its verbose nature and constant switching between XML and non-XML formats can...
really be a drain on precious processing power. Fortunately, this type of functionality fits very neatly with the appliance model, where a dedicated piece of external hardware can provide an offload for XML processing and even hardware-assisted acceleration. Vendors such as IBM, Layer 7 and others have moved in to offer XML acceleration in appliance formats, while others like Intel claim to offer similar benefits with a software-only model running on a dedicated but general-purpose server.
But these companies are not standing still. This appliance model for XML handling, whether a hardware appliance or the oxymoronic ‘software appliance’ mooted by Intel, offers the opportunity to do more than just plain XML acceleration. The hardware appliance in particular is an excellent vehicle for offering XML security/firewall functionality, offering a tamper-proof environment that is ideal for the DMZ. Then there is the possibility of moving more infrastructure functionality into the appliance to handle broader XML-related needs such as ESB-style messaging and data format mapping. These are all important expansion opportunities for appliance vendors, and there are already a wide range of value-add appliance-based offerings around XML.
However the most interesting change in the marketplace is the shifting needs driving purchases of these devices. Whereas initially the major driving force might have been to offload and optimize XML handling, the key focus now is to use the appliances to remove complexity from XML networks. Service oriented architecture (SOA) is still a big driver of XML usage, and as SOA usage expands the infrastructure required to handle it can become complex. In addition, the wider the SOA network spreads through a user organization and beyond, the harder skills issues bite.
The appliance offers an extremely attractive answer to these problems, not only addressing some of the performance issues through the XML acceleration but more importantly consolidating functions from multiple servers into a single, pre-packaged and pre-loaded device that can be remotely configured. In addition, this consolidation into tamper-proof hardware devices provides the ideal point at which to control XML traffic security, governance and performance. In this context, performance no longer means the speed of handling XML operations, but instead covers the end to end performance of the overall XML network. In other words, these devices provide throttling points where uneven XML traffic patterns can be smoothed out and rationalized.
One scenario where the security angle plays strongly is in the interactions within a cloud computing model. Most cloud usage involves a significant amount of data and applications remaining in the local environment and interoperating with those elements that are suitable for cloud deployment. With XML being the preferred standard for the traffic, the XML appliance can offer a controlled and secure gateway between the cloud and the internal processing environment.
XML accelerators may have started from a very narrow base of simply making XML processing faster and more cost-effective, but the whole concept has now blossomed into a much wider market of specialized XML appliances that can simplify infrastructure, ensure security and optimize performance at an end-to-end level.