Computer Unique Identifier (UID)


In order to identify computers, ISL AlwaysOn will send certain information to ISL Conference Proxy.

In ISL AlwaysOn 2.2.4, a change was made to the way this works so that cloned computers could be identified better.

ISL AlwaysOn 2.2.4+

UID, hash of OS unique string and Mac list is sent to ISL Conference Proxy. The hash of unique string is additional information to previous versions, this helps ISL Conference Proxy to detect cloned computers.


ISL AlwaysOn creates a unique identifier for each computer added to your list.

On Windows this is located in the registry at this location: HKLM\SOFTWARE\WOW6432Node\ISL Online\ISL AlwaysOn\uid

On Mac, the file structure is translated to that of unix like systems. So it is stored at this location: /etc/islonline/ISL+AlwaysOn/uid

Generation of uid

In ISL AlwaysOn 2.2.4+, uid is an md5 of the OS and System unique identifier as well as a random string (that also includes a timestamp).

Using the OS and System unique identifier enables ISL AlwaysOn to identify a cloned computer.

Example of uid: 96c1a77e8757dd565602aac4c68794b1-5904-1450343627-589980421

  • 96c1a77e8757dd565602aac4c68794b1 is the md5 of the OS and System unique identifier
  • -5904-1450343627-589980421 is a random string

Pre ISL AlwaysOn 2.2.4

Before ISL AlwaysOn 2.2.4, only uid and Mac list is sent to ISL Conference Proxy.

Before ISL AlwaysOn 2.2.4, uid was a random string.

The reduced information meant that ISL AlwaysOn was unable to detect a cloned computer.

Tags: isl alwayson, cloning computers, uid, unique identifier

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