XML appliances proliferating

The beauty of XML is its platform independence and flexible yet structured format. On the flip side, XML documents are bandwidth hogs that require translation and need to be secured.

To satisfy XML's handling requirements, three start-ups have come out with appliances aimed at processing XML traffic quickly, securely and smartly. Each is emphasizing slightly different features, although their products overlap.

DataPower Technology is aiming for speed. Last month, the company announced the XA35 XML Accelerator, a network device built to process XML at wire speed and improve application response times. DataPower says its 1U (1.75-inch-high) XA35, which starts at $55,000, accelerates XML processing tenfold or more.

Forum Systems is tackling security. In June, the vendor released the Sentry 1500 hardware appliance for encrypting and decrypting XML content. The 1U Sentry 1500, which starts at $35,000, can protect the data within an XML document, not just the packet itself, Forum says. The Sentry 2500, a 2U (3.5-inch-high) model with built-in failover capability, is due this fall.

Sarvega is focusing on intelligent routing. In May, the company unveiled the XPE Switch, a content-aware switch that secures, routes and prioritizes XML traffic.

Sarvega's 4U (7-inch-high) XPE Switch, which starts at $100,000, can understand specific tags within an XML document and give priority to certain transactions, such as a sales order vs. a customer address change. The next version, due out by year-end, will be slimmer and include additional features for securing XML content.

At their most basic, these new devices off-load XML processing from application servers, which can get bogged down parsing, translating and routing XML documents. The devices sit behind a firewall and in front of Web and application servers. They read passing packets, perform required validation, translation and transformation tasks, and forward requests contained in the XML documents to an appropriate server.

"All these companies see XML as the next network traffic that needs to be tamed. And they have a good point," says Ron Schmelzer, senior analyst at ZapThink.

Traffic management for XML will become increasingly important as traffic levels multiply, experts say. ZapThink predicts burgeoning growth: While XML today accounts for less than 2% of enterprise network traffic, by 2006 almost 25% of LAN traffic will contain XML documents, the firm says.

XML's processing requirements differ from switching and network protocol routing, Schmelzer says.

"Part of what makes XML different from other kinds of network traffic is that you can't identify it by packets in the header," he says. "You have to be able to look at every piece of information on the network, and you have to decrypt it, decompress it, parse it and understand it. It can be a real challenge."

The emergence of dedicated devices to handle these tasks is a natural evolution, according to Forrester Research.

"As the volume of XML traffic running between firms multiplies, the tasks of routing, parsing and acting on traffic will overtax general-purpose processors," Forrester says.

For Hemscott, a business information and research company in London, an XML bottleneck was hindering customer service.

To compile financial reports that customers access over the Web, Hemscott was pulling data from an Oracle database and translating it from XML to HTML to generate dynamic Web content. But the bulky transformations were bogging down servers. By moving XML processing onto DataPower's XA35, Hemscott was able to get its custom reports to customers in less than 1 second, as opposed to 15 to 20 seconds.

Ray Beaumont, technical architect at Hemscott, says the firm looked first at software options, but couldn't find any that could yield "orders of magnitude faster" XML processing. Beaumont says he would have preferred a software solution over adding specialized hardware that could potentially fail, but DataPower's performance gains won him over.

"We had a good debate about all that, and I'm comfortable we made the right decision here," Beaumont says. "There's nothing really that came near the XA35 in terms of a software solution."

Forrester compares XML processing to IP routing, Secure Sockets Layer encryption and intrusion detection - tasks that initially were handled by general-purpose servers and migrated over time to dedicated hardware.

As demand grows, better-known hardware vendors likely will tackle XML processing, along with the start-ups. Companies such as Cisco and F5 Networks already make application-aware devices that handle Layer 7 traffic based on the content of that traffic. Optimizing those devices for XML traffic could be the next step, experts say.

F5 will get into the XML processing market, Schmelzer predicts.

"If they're already looking at traffic, they can start to look a little more deeply at things like XML traffic," he says.

Indeed, F5 confirms that it is looking into the area of XML acceleration, according to a spokesperson. But the company declined to detail its plans. n

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