A single KMS host can activate an unlimited number of KMS clients. KMS clients communicate with the KMS host over the local network on port TCP/1688 (default). KMS client computers (your Windows workstations and Windows Server hosts) can find the KMS host using DNS or static configuration. KMS is based on a client-server architecture. After that, your enterprise KMS clients can send activation requests to the KMS server and activate with it. The KMS infrastructure is very simple: install the Volume Activation Services role on Windows Server, add your KMS Host Key (from Microsoft Volume Licensing Service Center), and activate your corporate KMS server on Microsoft (perform this only once). The KMS activation server allows activating corporate versions of Windows OS and Microsoft Office products within the enterprise network.

KMS (Key Management Service) - this is an activation type for enterprise customers.MAK is recommended to use for activating Windows computers that rarely or never connect to the corporate network, or for small networks where the number of computers doesn’t meet the KMS activation threshold You must activate the Windows copy with the MAK key installed via the Internet or by phone. The number of activations is limited and depends on the type of your license agreement (Open, Select, or Enterprise Agreement).

MAK (Multiple Activation Keys) - MAK license is like a Retail (box) license, but allows the activation of several instances of Windows using a single product key (MAK).

They can use MAK or KMS keys for product activation. Microsoft offers two ways of Windows and MS Office activation for corporate customers under the Volume License program.

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