Understanding XML Signature

Ensuring the security of the Ajax based application requires security of the XML. As the universal mark-up tool to integrate the functions of the Ajax based application, developers should ensure XML security to prevent any future problems.

When XML is not secured data could be easily extracted without the approval of users. While securing XML is just optional, it is a highly recommended practice especially if you are building a data intensive application. Some see it as extra work, but it is essential if you are looking to build a powerful application.

The security of XML could be implemented through its syntax. Within the syntax, developers would be able to specify how XML could be secured. The process of dealing with syntax in securing XML is called XML Signature.

Through this technique, developers would be able to establish a secured application since XML would be digitally secured. Specifically, XML Signature could be used to secure XML documents so that developers would be able to implement simplified content with utmost security.

Forms of XML Signature

There are four forms of XML Signature. They are basically differentiated on the type of XML being secured.

• Resource – If the XML is within the application. The XML Document should be accessible through URL so that the signature could be easily implemented.

• Detached – If the XML Document is within the application but there is an additional resource that affects the XML Document. The additional resource that affects the document users the Detached XML Signature.

• Enveloped – This could exercised by developers if only a portion of the XML Document will be secured.

• Enveloping – This is a very specialized form of XML Signature. This goes with the enveloped form. However, this type of XML Signature is found inside the enveloped format.

Canonicalization

At first glance, implementing XML Signature is very simple. Developers would only have to use the signature on the headers which will automatically secure the entire application.

However, implementing XML Signature will not be easy since developers would have to deal with whitespace problems. The presence of whitespace could easily slowdown the application and halts the security of XML. Since whitespaces cannot be ignored since it is required for ease of development, another way should be created.

Answering this problem is the technique called “Canonicalization.” This is a tool that could be used on XML Signature so that it could be ported to be acceptable in an application.

This is where the complexity of XML Signature lies. There are developers who can easily deal with XML Signature but it might not be easy for other developers. With or without whitespace, XML Signature will most likely require Canonicalization so that JavaScript would immediately understand how XML will be implemented.

On the other hand, there are options for developers in terms of security. For example, the regular security implemented in websites (https://) should be a good way to increase the security of the application. But if you are looking to secure only your XML to increase the speed of the application, then the XML Signature is the better option.