In one of my clients Oracle Managed Cloud Services environments which is extremely locked down, they were experiencing terrible performance issues trying to go to WB Mason’s external punchout site.  It was taking upwards of 5 minutes to return the catalog pages.

Something was CLEARLY wrong. In this case it was DTD – and what is DTD?  Well, document type definition of course – which is a set of markup declarations that define a document type for an SGML-family markup language (SGML, XML, HTML). A Document Type Definition (DTD) defines the legal building blocks of an XML document. It defines the document structure with a list of legal elements and attributes. A DTD can be declared inline inside an XML document, or as an external reference. XML uses a subset of SGML DTD. As of 2009, newer XML namespace-aware schema languages (such as W3C XML Schema and ISO RELAX NG) have largely superseded DTDs. A namespace-aware version of DTDs is being developed as Part 9 of ISO DSDL.[2] DTDs persist in applications that need special publishing characters, such as the XML and HTML Character Entity References, which derive from larger sets defined as part of the ISO SGML standard effort. (Yes, I cut and pasted that from wikipedia DTD page )

So basically the cXML of the external punchout is trying to validate against an external reference which the application server is not allowed to go to because of firewall restrictions. In this case because the only items we had validating were these valid external punchout sites, it seemed logical to turn off DTD validation! Which you can do since 8.49 PeopleTools. The version my client is on is 8.54, so it turns out that it is really easy in 8.54 to turn off DTD validation.

In the Web Integration Broker Gateway configuration (integrationgateway.properties) file, there is a setting for DTD Validation, simply change this to “false” from “true” and reboot the web server and what was once extremely slow is now returning in fractions of a second.

There are other ways to work around this issue, but this is a relatively quick item you can test to validate if DTD is causing your performance issues.