XML and the Bandwidth Challenge
While hardware accelerators can offload the processing burden for an XML server, there's no easy way to use hardware to reduce the size of XML traffic. Strategies for overcoming the size problem include applying standard compression algorithms such as GZIP for reducing the size of the XML as travels across the network. Using GZIP encoding over HTTP transport is an established technique for improving the performance of Web applications. High traffic web sites often use GZIP to make their user’s experience faster, and the compression technology is widely used to make files smaller for download and exchange.
But with straight compression there's no free lunch. If you compress to reduce size you then need to do additional processing to expand the XML back to its original form.
As an alternatives to compression, binary XML is now under official discussion as part of the newly formed World Wide Web Consortium’s XML Binary Characterization Working Group (XBC). In November of 2005, the W3C announced a new working group, the Efficient XML Interchange (EXI) Working Group to examine the feasibility of the Binary XML recommendations from the XBC group. Chartered through December 2007, the EXI group will begin by considering existing solutions and will evaluate each in terms of implementability and performance against the requirements and use cases produced by the XBC Working Group. The challenge will be to accommodate the widely disparate requirements for the stakeholders in XML compression that range from mobile application developers looking to move short snippets of XML across low bandwidth mobile networks to oil and gas explorers dragging sensor arrays across the ocean floor and creating terabytes of XML for transport across networks. How these disparate requirements will be worked out remains to be seen.