A random value/GUID is generated in the Session log under the Client Machine Identification column. If also using incognito/in-private browsing methods, the Session Recovery feature will not work as expected.
The value is a UUID receiver from a call to the Win32_ComputerSystemProduct WMI class, which represents a product.
The details will be found in:http://msdn.microsoft.com/en-us/library/aa394105.aspx
Related ArticleAjax: In Sessions log, Client machine identification is not unique to the client device
If the UUID fails for any reason, the fallback will be the MAC address of the client machine of which there could be multiples as well given potential wireless and Ethernet network interface connections etc. The final fallback is the ComputerName.
Note: use of private browsing sessions in web browsers with the Ajax client will result in a unique Client Machine Identification value for every session that is not part of the same private session in the browser, there will be no common value in this use case.
In addition to the above, this will also impact the Session Recovery feature of QlikView as well, in that the bookmarks will not be usable given the user will be coming in as a unique ID every session, so customer running this scenario should not enable the Session Recovery feature in this case.