What exactly is the "Logon GUID"?

Giganews Newsgroups
Subject: What exactly is the "Logon GUID"?
Posted by:  Spin (Sp…@invalid.com)
Date: Tue, 26 Aug 2008


In the event log detail below, what exactly is the "Logon GUID" referring
to?  The transaction below represents a user named "TestUser" who accessed a
network share on "SQLServer", from a machine who's IP address was

Event Type: Success Audit
Event Source: Security
Event Category: Logon/Logoff
Event ID: 540
Date:  8/26/2008
Time:  2:06:10 PM
User:  DOMAIN\TestUser
Computer: SQLServer
Successful Network Logon:
  User Name: TestUser
  Domain:  DOMAIN
  Logon ID:  (0x0,0x55025)
  Logon Type: 3
  Logon Process: Kerberos
  Authentication Package: Kerberos
  Workstation Name:
  Logon GUID: {34942986-0087-5999-249a-e218464f6320}
  Caller User Name: -
  Caller Domain: -
  Caller Logon ID: -
  Caller Process ID: -
  Transited Services: -
  Source Network Address:
  Source Port: 0