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TPM recommendations

This article provides recommendations for Trusted Platform Module (TPM) technology for Windows.

For a basic feature description of TPM, see the Trusted Platform Module Technology Overview.

TPM design and implementation

Traditionally, TPMs are discrete chips soldered to a computer's motherboard. Such implementations allow the computer's original equipment manufacturer (OEM) to evaluate and certify the TPM separate from the rest of the system. Discrete TPM implementations are common. However, they can be problematic for integrated devices that are small or have low power consumption. Some newer TPM implementations integrate TPM functionality into the same chipset as other platform components while still providing logical separation similar to discrete TPM chips.

TPMs are passive: they receive commands and return responses. To realize the full benefit of a TPM, the OEM must carefully integrate system hardware and firmware with the TPM to send it commands and react to its responses. TPMs were originally designed to provide security and privacy benefits to a platform's owner and users, but newer versions can provide security and privacy benefits to the system hardware itself. Before it can be used for advanced scenarios, however, a TPM must be provisioned. Windows automatically provisions a TPM, but if the user is planning to reinstall the operating system, they may need to clear the TPM before reinstalling so that Windows can take full advantage of the TPM.

The Trusted Computing Group (TCG) is the nonprofit organization that publishes and maintains the TPM specification. The TCG exists to develop, define, and promote vendor-neutral, global industry standards. These standards support a hardware-based root of trust for interoperable trusted computing platforms. The TCG also publishes the TPM specification as the international standard ISO/IEC 11889, using the Publicly Available Specification Submission Process that the Joint Technical Committee 1 defines between the International Organization for Standardization (ISO) and the International Electrotechnical Commission (IEC).

OEMs implement the TPM as a component in a trusted computing platform, such as a PC, tablet, or phone. Trusted computing platforms use the TPM to support privacy and security scenarios that software alone can't achieve. For example, software alone can't reliably report whether malware is present during the system startup process. The close integration between TPM and platform increases the transparency of the startup process and supports evaluating device health by enabling reliable measuring and reporting of the software that starts the device. Implementation of a TPM as part of a trusted computing platform provides a hardware root of trust-that is, it behaves in a trusted way. For example, if a key stored in a TPM has properties that disallow exporting the key, that key truly can't leave the TPM.

The TCG designed the TPM as a low-cost, mass-market security solution that addresses the requirements of different customer segments. There are variations in the security properties of different TPM implementations just as there are variations in customer and regulatory requirements for different sectors. In public-sector procurement, for example, some governments clearly define security requirements for TPMs whereas others don't.

TPM 1.2 vs. 2.0 comparison

From an industry standard, Microsoft has been an industry leader in moving and standardizing on TPM 2.0, which has many key realized benefits across algorithms, crypto, hierarchy, root keys, authorization, and NV RAM.

Why TPM 2.0?

TPM 2.0 products and systems have important security advantages over TPM 1.2, including:

  • The TPM 1.2 spec only allows for the use of RSA and the SHA-1 hashing algorithm.
  • For security reasons, some entities are moving away from SHA-1. Notably, NIST requires many federal agencies to move to SHA-256 as of 2014, and technology leaders, including Microsoft and Google have removed support for SHA-1 based signing or certificates in 2017.
  • TPM 2.0 enables greater crypto agility by being more flexible with respect to cryptographic algorithms.
    • TPM 2.0 supports newer algorithms, which can improve drive signing and key generation performance. For the full list of supported algorithms, see the TCG Algorithm Registry. Some TPMs don't support all algorithms.
    • For the list of algorithms that Windows supports in the platform cryptographic storage provider, see CNG Cryptographic Algorithm Providers.
    • TPM 2.0 achieved ISO standardization (ISO/IEC 11889:2015).
    • Use of TPM 2.0 may help eliminate the need for OEMs to make exception to standard configurations for certain countries and regions.
  • TPM 2.0 offers a more consistent experience across different implementations.
    • TPM 1.2 implementations vary in policy settings. This may result in support issues as lockout policies vary.
    • TPM 2.0 lockout policy is configured by Windows, ensuring a consistent dictionary attack protection guarantee.
  • While TPM 1.2 parts are discrete silicon components, which are typically soldered on the motherboard, TPM 2.0 is available as a discrete (dTPM) silicon component in a single semiconductor package, an integrated component incorporated in one or more semiconductor packages - alongside other logic units in the same package(s), and as a firmware (fTPM) based component running in a trusted execution environment (TEE) on a general purpose SoC.

Note

TPM 2.0 is not supported in Legacy and CSM Modes of the BIOS. Devices with TPM 2.0 must have their BIOS mode configured as Native UEFI only. The Legacy and Compatibility Support Module (CSM) options must be disabled. For added security Enable the Secure Boot feature.

Installed Operating System on hardware in legacy mode will stop the OS from booting when the BIOS mode is changed to UEFI. Use the tool MBR2GPT before changing the BIOS mode which will prepare the OS and the disk to support UEFI.

Discrete, Integrated, or Firmware TPM?

There are three implementation options for TPMs:

  • Discrete TPM chip as a separate component in its own semiconductor package.
  • Integrated TPM solution, using dedicated hardware integrated into one or more semiconductor packages alongside, but logically separate from, other components.
  • Firmware TPM solution, running the TPM in firmware in a Trusted Execution mode of a general purpose computation unit.

Windows uses any compatible TPM in the same way. Microsoft doesn't take a position on which way a TPM should be implemented and there's a wide ecosystem of available TPM solutions, which should suit all needs.

Is there any importance for TPM for consumers?

For end consumers, TPM is behind the scenes but is still relevant. TPM is used for Windows Hello, Windows Hello for Business and in the future, will be a component of many other key security features in Windows. TPM secures the PIN, helps encrypt passwords, and builds on our overall Windows experience story for security as a critical pillar. Using Windows on a system with a TPM enables a deeper and broader level of security coverage.

TPM 2.0 Compliance for Windows

Windows for desktop editions (Home, Pro, Enterprise, and Education)

  • Since July 28, 2016, all new device models, lines, or series (or if you're updating the hardware configuration of an existing model, line, or series with a major update, such as CPU, graphic cards) must implement and enable by default TPM 2.0 (details in section 3.7 of the Minimum hardware requirements page). The requirement to enable TPM 2.0 only applies to the manufacturing of new devices. For TPM recommendations for specific Windows features, see TPM and Windows Features.

IoT Core

  • TPM is optional on IoT Core.

Windows Server 2016

  • TPM is optional for Windows Server SKUs unless the SKU meets the other qualification (AQ) criteria for the Host Guardian Services scenario in which case TPM 2.0 is required.

TPM and Windows Features

The following table defines which Windows features require TPM support.

Windows Features TPM Required Supports TPM 1.2 Supports TPM 2.0 Details
Measured Boot Yes Yes Yes Measured Boot requires TPM 1.2 or 2.0 and UEFI Secure Boot. TPM 2.0 is recommended since it supports newer cryptographic algorithms. TPM 1.2 only supports the SHA-1 algorithm, which is being deprecated.
BitLocker No Yes Yes TPM 1.2 or 2.0 are supported but TPM 2.0 is recommended. Device Encryption requires Modern Standby including TPM 2.0 support
Device Encryption Yes N/A Yes Device Encryption requires Modern Standby/Connected Standby certification, which requires TPM 2.0.
App Control for Business No Yes Yes
System Guard (DRTM) Yes No Yes TPM 2.0 and UEFI firmware is required.
Credential Guard No Yes Yes Windows 10, version 1507 (End of Life as of May 2017) only supported TPM 2.0 for Credential Guard. Beginning with Windows 10, version 1511, TPM 1.2 and 2.0 are supported. Paired with System Guard, TPM 2.0 provides enhanced security for Credential Guard. Windows 11 requires TPM 2.0 by default to facilitate easier enablement of this enhanced security for customers.
Device Health Attestation Yes Yes Yes TPM 2.0 is recommended since it supports newer cryptographic algorithms. TPM 1.2 only supports the SHA-1 algorithm, which is being deprecated.
Windows Hello/Windows Hello for Business No Yes Yes Microsoft Entra join supports both versions of TPM, but requires TPM with keyed-hash message authentication code (HMAC) and Endorsement Key (EK) certificate for key attestation support. TPM 2.0 is recommended over TPM 1.2 for better performance and security. Windows Hello as a FIDO platform authenticator takes advantage of TPM 2.0 for key storage.
UEFI Secure Boot No Yes Yes
TPM Platform Crypto Provider Key Storage Provider Yes Yes Yes
Virtual Smart Card Yes Yes Yes
Certificate storage No Yes Yes TPM is only required when the certificate is stored in the TPM.
Autopilot No N/A Yes If you intend to deploy a scenario, which requires TPM (such as white glove and self-deploying mode), then TPM 2.0 and UEFI firmware are required.
SecureBIO Yes No Yes TPM 2.0 and UEFI firmware is required.

OEM Status on TPM 2.0 system availability and certified parts

Government customers and enterprise customers in regulated industries may have acquisition standards that require use of common certified TPM parts. As a result, OEMs, who provide the devices, may be required to use only certified TPM components on their commercial class systems. For more information, contact your OEM or hardware vendor.