WebSphere DataPower XML Accelerator XA35

DataPower XA35 XML Accelerator

The WebSphere DataPower XA35 is the first DataPower product, the least expensive with the simplest feature set.

Why use it?

Its speciality is to validate incoming XML documents, and to transform them into the XML documents you really want. It can also validate and/or transform XML content on the way out as well.

Its killer app is to use as a validating parser instead of the parser in your app server, leaving the app server's CPU available for more valuable tasks like running your app's business logic. Instead of your app validating incoming XML, pass the XML through DataPower to validate, then the app receives only valid documents.

Details

You like to hope that callers sending you XML content or invoking your Web services will be careful to only send you well-formed and valid XML, but some senders aren't so careful. Also, it's possible for good XML to get corrupted coming across the network. XML parsers assume the content is well-formed, and waste a lot of time and CPU when it's not. Validating XML is very expensive, and so has a significant negative impact on performance. So it's better for your apps if they can assume content is well-formed and valid, and delegate this verification to someone/something else.

The XA35 is this something else. It excels at XML verification, performing it at wire speed. Thus, don't have your app do this verification, let DataPower do it.

The XML parser in WebSphere Application Server is not a validating parser, because validation would impact WAS's performance too much. So if you want to validate XML going into WAS, the best way to do it is to pass that traffic through DataPower first. See Validating XML in WAS.

Likewise, you hope that XML traffic comes in using the schema your app prefers. But realistically, some callers may have other formats they prefer, so you accommodate those to be helpful. But to be able to use those, you have to transform the traffic from the incoming format to the format your app expects. Again, this transformation can be a significant performance hit, one that your app and your valuable WAS licenses and server computers shouldn't incur. Instead, if the transformation can be performed using XSL, then let the DataPower box do it. Its transformation capabilities are super scalable, at wire speeds, and lessen the load on your app.