| Step | Description |
|---------|---------|
|**1** | Contoso configures tenant restrictions in its cross-tenant access settings to block all external accounts and external apps. Contoso adds enforcement signaling with the tenant restrictions v2 header via either [universal tenant restrictions v2](#option-1-use-universal-tenant-restrictions-v2-as-part-of-microsoft-entra-global-secure-access) or a [corporate proxy](#option-2-set-up-tenant-restrictions-v2-on-your-corporate-proxy). Microsoft Entra ID enforces the tenant restrictions v2 policy when the header is present on the request. |
|**2** | The user of a Contoso-managed device tries to sign in to an external app by using an account from an unknown tenant. The tenant restrictions v2 HTTP header, with Contoso's tenant ID and the tenant restrictions policy ID, is added to the authentication request. |
|**3** | *Authentication plane protection:* Microsoft Entra ID enforces Contoso's tenant restrictions v2 policy and blocks external accounts from accessing external tenants during the authentication. |
|**4** | *Data plane protection (preview):* Microsoft Entra ID blocks any anonymous access to Microsoft Forms, SharePoint files, or Microsoft Teams meetings. Microsoft Entra ID also blocks user access to the resource with an infiltrated token. |
|||
| Feature |Tenant restrictions v1 |Tenant restrictions v2 |
|----------------------|---------|---------|
|**Policy enforcement** | The corporate proxy enforces the tenant restrictions policy in the Microsoft Entra ID control plane. | Options: <br></br>- Universal tenant restrictions in Global Secure Access provide authentication plane support on all platforms. <br></br>- In corporate proxy header injection, the corporate proxy sets tenant restrictions v2 signals on all traffic. <br></br>- Windows device management provides both authentication plane and data plane protection. Devices are configured to point Microsoft traffic to the tenant restrictions policy. The policy is enforced in the cloud. |
|**Policy enforcement limitation** | You can manage corporate proxies by adding tenants to the Microsoft Entra traffic allowlist. The character limit of the header value in `Restrict-Access-To-Tenants: <allowed-tenant-list>` limits the number of tenants that you can add. | This feature is managed by a cloud policy in the cross-tenant access policy. A default policy is created at the tenant level, and a partner policy is created for each external tenant. |
|**Malicious tenant requests** | Microsoft Entra ID blocks malicious tenant authentication requests to provide authentication plane protection. | Microsoft Entra ID blocks malicious tenant authentication requests to provide authentication plane protection. |
|**Granularity** | This feature is limited to tenants and all Microsoft accounts. | This feature includes tenant, user, group, and application granularity. (User-level granularity isn't supported with Microsoft accounts.) |
### Step 3: Enable tenant restrictions v2 on the corporate proxy
You can configure the corporate proxy to enable client-side tagging of the tenant restrictions V2 header by using the following corporate proxy setting: `sec-Restrict-Tenant-Access-Policy: <DirectoryID>:<policyGUID>`.
In that setting, replace `<DirectoryID>` with your Microsoft Entra tenant ID. Replace `<policyGUID>` with the object ID for your cross-tenant access policy.
| Step | Description |
|---------|---------|
|**1** | Contoso configures tenant restrictions in its cross-tenant access settings to block all external accounts and external apps. Contoso adds enforcement signaling with the tenant restrictions v2 header via either [universal tenant restrictions v2](#option-1-use-universal-tenant-restrictions-v2-as-part-of-microsoft-entra-global-secure-access) or a [corporate proxy](#option-2-set-up-tenant-restrictions-v2-on-your-corporate-proxy). Microsoft Entra ID enforces the tenant restrictions v2 policy when the header is present on the request. |
|**2** | The user of a Contoso-managed device tries to sign in to an external app by using an account from an unknown tenant. The tenant restrictions v2 HTTP header, with Contoso's tenant ID and the policy ID for tenant restrictions, is added to the authentication request. |
|**3** | *Authentication plane protection:* Microsoft Entra ID enforces Contoso's tenant restrictions v2 policy and blocks external accounts from accessing external tenants during the authentication. |
|**4** | *Data plane protection (preview):* Microsoft Entra ID blocks any anonymous access to Microsoft Forms, SharePoint files, or Microsoft Teams meetings. Microsoft Entra ID also blocks user access to the resource with an infiltrated token. |
|||
| Feature |Tenant restrictions v1 |Tenant restrictions v2 |
|----------------------|---------|---------|
|**Policy enforcement** | The corporate proxy enforces the tenant restrictions policy on the Microsoft Entra ID control plane. | Options: <br></br>- Universal tenant restrictions in Global Secure Access provide authentication plane support on all platforms. <br></br>- In corporate proxy header injection, the corporate proxy sets tenant restrictions v2 signals on all traffic. <br></br>- Windows device management provides both authentication plane and data plane protection. Devices are configured to point Microsoft traffic to the tenant restrictions policy. The policy is enforced in the cloud. |
|**Policy enforcement limitation** | You can manage corporate proxies by adding tenants to the Microsoft Entra traffic allowlist. The character limit of the header value in `Restrict-Access-To-Tenants: <allowed-tenant-list>` limits the number of tenants that you can add. | This feature is managed by a cloud policy in the cross-tenant access policy. A default policy is created at the tenant level, and a partner policy is created for each external tenant. |
|**Malicious tenant requests** | Microsoft Entra ID blocks malicious tenant authentication requests to provide authentication plane protection. | Microsoft Entra ID blocks malicious tenant authentication requests to provide authentication plane protection. |
|**Granularity** | This feature is limited to tenants and all Microsoft accounts. | This feature includes tenant, user, group, and application granularity. (User-level granularity isn't supported with Microsoft accounts.) |
### Step 3: Enable tenant restrictions v2 on the corporate proxy
You can configure the corporate proxy to enable client-side tagging of the tenant restrictions v2 header by using the following corporate proxy setting: `sec-Restrict-Tenant-Access-Policy: <DirectoryID>:<policyGUID>`.
In that setting, replace `<DirectoryID>` with your Microsoft Entra tenant ID. Replace `<policyGUID>` with the object ID for your cross-tenant access policy.