What is the Key Management Service process in Windows 7


Windows 7 - KMS activation terms

When discussing the Key Management Service (KMS), it helps first to understand the different terms associated with KMS. Once you grasp the terms, the process is much easier to understand. I've outlined many of the basic terms here:

KMS host - The server hosting the KMS service is commonly referred to as the KMS host.

KMS client - Clients configured to contact the KMS host are referred to as KMS clients.

DNS publication - A KMS host can publish Domain Name System (DNS) SRV records (server records) to the DNS server using dynamic DNS within a Microsoft domain. If DNS isn't configured to allow dynamic updates, the SRV records must be manually configured on the DNS server so that KMS clients can locate the KMS host.

Activation threshold - The minimum number of clients a network must have for KMS activation to work is referred to as the activation threshold. A network must have at least 5 servers for server activation to work or a combination of at least 25 servers and clients for client activation to work. The KMS host tracks this threshold, and if the threshold isn't reached or the number of clients falls below this threshold, it will no longer activate the clients. KMS clients that aren't activated because the activation threshold is not met will request activation every two hours.

Activation validity interval - After activation by a KMS host, KMS clients will remain activated for 180 days. If the KMS client has not connected to a KMS server within 180 days, the activation will be invalidated. Clients attempt to connect every seven days, and when they connect, this 180-day counter is reset.

Activation count - The current number of clients that are being activated by KMS is tracked using unique client machine identification designation (CMID) records. Clients attempt to contact the KMS server every seven days, and the KMS server renews this CMID when the client activates or reactivates. If the client doesn't renew within 30 days, the CMID is discarded and is no longer counted toward the activation threshold.

This is an important concept. Your network may have reached the threshold of 25, and then two systems are decommissioned or taken on the road by sales people. Within 30 days, the CMID for these two systems will be removed from the KMS host, and the count will be at 23. Clients will no longer be activated, and within seven days all 23 remaining systems will be trying to activate every two hours. Even though the clients will stay activated for 180 days, these failures will result in errors in the event logs. Once two new clients are added to the network, everything will normalize.

KMS activation process for Windows 7

The KMS activation process is ongoing, requiring the KMS clients to connect to the KMS host periodically. Before the process can start, an SRV record must exist in DNS so the clients can reach the KMS server. Normally, dynamic update will be configured in DNS, which allows the KMS service on a KMS host to publish SRV records automatically to DNS. Once this is configured, no further steps are required. KMS clients then query DNS to locate the KMS host.

Working with KMS

In order for the KMS to respond to activation requests, the firewall needs to be properly configured on the KMS server. If the Windows firewall is being used, the KMS Traffic exception can be enabled. If a third-party firewall is being used, you'll need to open port 1688. In addition, you can use the Software Licensing Management Tool (slmgr.vbs) to configure and manage specific settings on the KMS server.

Legal Disclaimer

Our website is not responsible for the information contained by this article. Articleinput.com is a free articles resource thus practically any visitor can submit an article. However if you notice any copyrighted material, please contact us and we will remove the article(s) in discussion right away.

Note: This article was sent to us by: Fred N. Halbert at 09272010

Related Articles

1. How to create a bootable VHD in Windows 7
Create a Bootable VHD 1. Turn on the Windows Vista system and place the Windows 7 installation DVD in the system. When the system starts, select the option to boo...

2. Windows XP Mode can be a good solution for who considers Windows 7
Windows XP Mode Windows XP Mode is a virtualization technology that addresses a specific problem that prevented many people from moving from Windows XP to Windo...

3. How to publish applications from Windows XP Mode in Windows 7
1. From the Windows 7 host machine, click Start > All Programs > Windows Virtual PC > Windows Virtual PC. This will launch the Windows Virtual PC console. ...

4. Advantages of all three Windows 7 editions
Advantages of Windows 7 If you're wondering why Windows 7 is the pick of the Microsoft user - and why you should upgrade from an older Windows version, such as ...

5. The Windows 7 help system is the best of all Windows versions
Windows 7 Help System Windows 7 comes with the best Help system that has ever shipped with any version of Windows. It even has online components that you can re...

6. Windows 7 basic options you should know and use
Sleep mode Sleep mode immediately puts your computer in a low-power mode: The monitor turns black, and Windows seems to shut down. You can, however, return to...

7. Windows 7 taskbar menus and toolbars
Windows 7 taskbar The Windows 7 taskbar is that little strip of buttons and miniature icons that runs along the bottom of the screen. Like the Start menu, the...

8. Windows 7 install integration components and other tips
After installing an OS using Virtual PC, you may notice that things aren't running the way you'd like them to run. For one thing, every time you click within a Virtual...

9. How to manage client licensing in Windows 7
Windows 7 client licensing management Software developers have been battling software counterfeiting (often called pirating or software piracy) since the ...