Kerberos Redux?

With the arrival of Windows Server 2003 we might be forgiven if we think that Kerberos, a "secure method for authenticating a request for a service in a computer network", is on its way out. After all, Microsoft have been seen as the principal torch bearer. What is clear in Server 2003 is that Microsoft are starting to push PKI as the way forward. Talk to Microsoft people and you might find an unusual ambivalence to Kerberos.

In addition to which, there has always been the view in parts of the industry, both vendor and user, that Kerberos does not scale and is not rich enough to support eCommerce.

It is somewhat refreshing therefore to find a new Kerberos product on the market. CyberSafe is a UK-based company that phoenixed out of the demise of the US parent.

The release of CyberSafe's TrustBroker WebAccess product underlines the belief in the Company that Kerberos still has much to offer. WebAccess provides Kerberos authentication services between workstations running a Web browser and Web servers, or Web proxy servers accessible across the network. Used in conjunction with the optional WebAccess Application Server, the authenticated identity of the user can also be securely presented to JAVA servlets running on an application server.

WebAccess uses the Kerberos protocol to authenticate users when they login to the Windows domain. The credentials obtained during this login can be used by the browser to present a security context to the Web server or Web proxy server - meaning that the user only needs to authenticate once when they login to the workstation - and effectively providing Web single sign-on.

An additional benefit is that WebAccess authentication between the browser/workstation and the Web server or Web proxy server is mutual, so that the server trusts who the user is, and the users browser is able to trust the identity of the server, without the addition of more technology.

Compare this to more commonly used Web authentication techniques. Typically, a domain cookie maintains a context for user access to a Web server, so they don't have to re-authenticate for each URL accessed in the same domain. Once the Web server determines the identity of the user at the browser, it is able to use this to determine their access rights or entitlement.

In a multi-tier application architecture, the cookie is then the reference point for further authentication requirements. CyberSafe's proposition is that their approach offers greater in-line security as the Web server to accesses other tiers across the network on behalf of the user. For example, a database requiring authentication of the user to determine access rights.

The attractiveness of WebAccess is that it offers an alternative to PKI and vendors such as RSA, Secure Computing and Arcot. If you have a large Kerberos installation already it might allow you to extend it without the interoperability challenges you might otherwise face.

CyberSafe is the only real independent player in the Kerberos space. Microsoft adopted CyberSafe's technology in Windows 2000. There remain questions over whether CyberSafe can compete, not just with alternative technologies but also with companies such as Microsoft, Sun and HP who all provide Kerberos support out-the-box and whose channel partners could build similar solutions to CyberSafe's WebAccess.

This seems a solution for die-hard Kerberos supporters. CyberSafe are looking at other market areas where they think Kerberos is uniquely suited and it might be these that secure the future of the company. © IT-Analysis.com