DirectAccess and Always On VPN with Trusted Platform Module (TPM) Certificates

DirectAccess and Always On VPN with Trusted Platform Module (TPM) CertificatesTo enhance security when provisioning certificates for DirectAccess (computer) or Windows 10 Always On VPN (user) it is recommended that private keys be stored on a Trusted Platform Module (TPM) on the client device. A TPM is a dedicated security processor included in nearly all modern computers. It provides essential hardware protection to ensure the highest levels of integrity for digital certificates and is used to generate, store, and restrict the use of cryptographic keys. It also includes advanced security and protection features such as key isolation, non-exportability, and anti-hammering to prevent brute-force attacks.

To ensure that private keys are created and stored on a TPM, the certificate template must be configured to use the Microsoft Platform Crypto Provider. Follow the steps below to configure a certificate template required to use a TPM.

  1. Open the Certificate Templates management console (certtmpl.msc) and duplicate an existing certificate template. For example, if creating a certificate for DirectAccess, duplicate the Workstation Authentication certificate template. For Always On VPN, duplicate the User certificate template.
  2. On the Compatibility tab, ensure the Certification Authority and Certificate recipient compatibility settings are set to a minimum of Windows Server 2008 and Windows Vista/Server 2008, respectively.DirectAccess and Always On VPN with Trusted Platform Module (TPM) Certificates
  3. Select the Cryptography tab.
  4. Choose Key Storage Provider from the Provider Category drop down list.
  5. Choose the option Requests must use one of the following providers and select Microsoft Platform Crypto Provider.DirectAccess and Always On VPN with Trusted Platform Module (TPM) Certificates

Note: If Microsoft Platform Crypto Provider does not appear in the list above, got to the Request Handling tab and uncheck the option Allow private key to be exported.

Complete the remaining certificate configuration tasks (template display name, subject name, security settings, etc.) and publish the certificate template. Client machines configured to use this template will now have a certificate with private key fully protected by the TPM.

Additional Resources

Trusted Platform Module (TPM) Fundamentals

DirectAccess and Always On VPN Certificate Auto Enrollment

Deploying NetMotion Mobility in Azure

NetMotion MobilityOne of the many advantages NetMotion Mobility offers is that it requires no proprietary hardware to deliver its advanced capabilities and performance. It is a software solution that can be installed on any physical or virtual Windows server. This provides great deployment flexibility by allowing administrators to deploy this remote access solution on their existing virtual infrastructure, which is much less costly than investing in dedicated hardware or virtual appliances.

Cloud Deployment

As customers begin moving their traditional on-premises infrastructure to the cloud, it’s good to know that NetMotion Mobility is fully supported in popular public cloud platforms such as Microsoft Azure. Installing and configuring Mobility on a server in Azure requires a few important changes to a standard Azure VM deployment however. Below is detailed guidance for installing and configuring NetMotion Mobility on a Windows Server 2016 virtual machine hosted in the Microsoft Azure public cloud.

Azure Networking Configuration

Before installing the NetMotion Mobility software, follow the steps below to configure the Azure VM with a static public IP address and enable IP forwarding on the internal network interface.

  1. In the Azure management portal, select the NetMotion Mobility virtual machine and click Networking.
  2. Click on the public-facing network interface.
  3. In the Settings section click IP configurations.
  4. In the IP configurations section click on the IP configuration for the network interface.
  5. In the Public IP address setting section click Enabled for the Public IP address.
  6. Click Configure required settings for the IP address.
  7. Click Create New.
  8. Enter a descriptive name and select Static as the assignment method.
    Deploying NetMotion Mobility in Azure
  9. Click OK
  10. Click Save.Deploying NetMotion Mobility in AzureNote: The process of saving the network interface configuration takes a few minutes. Be patient!
  11. Note the public IP address, as this will be used later during the Mobility configuration.
  12. Close the IP address configuration blade.
  13. In the IP forwarding settings section click Enabled for IP forwarding.Deploying NetMotion Mobility in Azure
  14. Click Save.

NetMotion Mobility Installation

Proceed with the installation of NetMotion Mobility. When prompted for the external address, enter the public IP address created previously.

Deploying NetMotion Mobility in Azure

Next choose the option to Use pool of virtual IP addresses. Click Add and enter the starting and ending IP addresses, subnet prefix length, and default gateway and click OK.

Deploying NetMotion Mobility in Azure

Complete the remaining NetMotion Mobility configuration as required.

Azure Routing Table

A user defined routing table must be configured to ensure that NetMotion Mobility client traffic is routed correctly in Azure. Follow the steps below to complete the configuration.

  1. In the Azure management portal click New.
  2. In the Search the Marketplace field enter route table.
  3. In the results section click Route table.
  4. Click Create.
  5. Enter a descriptive name and select a subscription, resource group, and location.
  6. Click Create.

Deploying NetMotion Mobility in Azure

Once the deployment has completed successfully, click Go to resource in the notifications list.

Deploying NetMotion Mobility in Azure

Follow the steps below to add a route to the route table.

  1. In the Settings sections click Routes.
  2. Click Add.
  3. Enter a descriptive name.
  4. In the Address prefix field enter the subnet used by mobility clients defined earlier.
  5. Select Virtual appliance as the Next hop type.
  6. Enter the IP address of the NetMotion Mobility server’s internal network interface.
  7. Click OK.Deploying NetMotion Mobility in Azure
  8. Click Subnets.
  9. Click Associate.
  10. Click Choose a virtual network and select the network where the NetMotion Mobility gateway resides.
  11. Click Choose a subnet and select the subnet where the NetMotion Mobility gateway’s internal network interface resides.
  12. Click OK.

Note: If clients connecting to the NetMotion Mobility server need to access resources on-premises via a site-to-site gateway, be sure to associate the route table with the Azure gateway subnet.

Azure Network Security Group

A network security group must be configured to allow inbound UDP port 5008 to allow external clients to reach the NetMotion Mobility gateway server. Follow the steps below to create and assign a network security group.

  1. In the Azure management portal click New.
  2. In the Search the Marketplace field enter network security group.
  3. In the results section click Network security group.
  4. Click Create.
  5. Enter a descriptive name and select a subscription, resource group, and location.
  6. Click Create.

Deploying NetMotion Mobility in Azure

Once the deployment has completed successfully, click Go to resource in the notifications list.

Deploying NetMotion Mobility in Azure

Follow the steps below to configure the network security group.

  1. In the Settings section click Inbound security rules.
  2. Click Add.
  3. Enter 5008 in the Destination port ranges field.
  4. Select UDP for the protocol.
  5. Select Allow for the action.
  6. Enter a descriptive name.
  7. Click OK.
    Deploying NetMotion Mobility in Azure
  8. Click Network Interfaces.
  9. Click Associate.
  10. Select the external network interface of the NetMotion Mobility gateway server.

Summary

After completing the steps above, install the client software and configure it to use the static public IP address created previously. Alternatively, configure a DNS record to point to the public IP address and specify the Fully Qualified Domain Name (FQDN) instead of the IP address itself.

Additional Resources

Enabling Secure Remote Administration for the NetMotion Mobility Console

NetMotion Mobility Device Tunnel Configuration

NetMotion Mobility as an Alternative to Microsoft DirectAccess

NetMotion Mobility and Microsoft DirectAccess Comparison Whitepaper

NetMotion and Microsoft DirectAccess On-Demand Webinar

What is the Difference Between DirectAccess and Always On VPN?

Always On VPN Device Tunnel Configuration Guidance Now AvailableDirectAccess has been around for many years, and with Microsoft now moving in the direction of Always On VPN, I’m often asked “What’s the difference between DirectAccess and Always On VPN?” Fundamentally they both provide seamless and transparent, always on remote access. However, Always On VPN has a number of advantages over DirectAccess in terms of security, authentication and management, performance, and supportability.

Security

DirectAccess provides full network connectivity when a client is connected remotely. It lacks any native features to control access on a granular basis. It is possible to restrict access to internal resources by placing a firewall between the DirectAccess server and the LAN, but the policy would apply to all connected clients.

Windows 10 Always On VPN includes support for granular traffic filtering. Where DirectAccess provides access to all internal resources when connected, Always On VPN allows administrators to restrict client access to internal resources in a variety of ways. In addition, traffic filter policies can be applied on a per-user or group basis. For example, users in accounting can be granted access only to their department servers. The same could be done for HR, finance, IT, and others.

Authentication and Management

DirectAccess includes support for strong user authentication with smart cards and one-time password (OTP) solutions. However, there is no provision to grant access based on device configuration or health, as that feature was removed in Windows Server 2016 and Windows 10. In addition, DirectAccess requires that clients and servers be joined to a domain, as all configuration settings are managed using Active Directory group policy.

Windows 10 Always On VPN includes support for modern authentication and management, which results in better overall security. Always On VPN clients can be joined to an Azure Active Directory and conditional access can also be enabled. Modern authentication support using Azure MFA and Windows Hello for Business is also supported. Always On VPN is managed using Mobile Device Management (MDM) solutions such as Microsoft Intune.

Performance

DirectAccess uses IPsec with IPv6, which must be encapsulated in TLS to be routed over the public IPv4 Internet. IPv6 traffic is then translated to IPv4 on the DirectAccess server. DirectAccess performance is often acceptable when clients have reliable, high quality Internet connections. However, if connection quality is fair to poor, the high protocol overhead of DirectAccess with its multiple layers of encapsulation and translation often yields poor performance.

The protocol of choice for Windows 10 Always On VPN deployments is IKEv2. It offers the best security and performance when compared to TLS-based protocols. In addition, Always On VPN does not rely exclusively on IPv6 as DirectAccess does. This reduces the many layers of encapsulation and eliminates the need for complex IPv6 transition and translation technologies, further improving performance over DirectAccess.

Supportability

DirectAccess is a Microsoft-proprietary solution that must be deployed using Windows Server and Active Directory. It also requires a Network Location Server (NLS) for clients to determine if they are inside or outside the network. NLS availability is crucial and ensuring that it is always reachable by internal clients can pose challenges, especially in very large organizations.

Windows 10 Always On VPN supporting infrastructure is much less complex than DirectAccess. There’s no requirement for a NLS, which means fewer servers to provision, manage, and monitor. In addition, Always On VPN is completely infrastructure independent and can be deployed using third-party VPN servers such as Cisco, Checkpoint, SonicWALL, Palo Alto, and more.

Summary

Windows 10 Always On VPN is the way of the future. It provides better overall security than DirectAccess, it performs better, and it is easier to manage and support.

Here’s a quick summary of some important aspects of VPN, DirectAccess, and Windows 10 Always On VPN.

Traditional VPN DirectAccess Always On VPN
Seamless and Transparent No Yes Yes
Automatic Connection Options None Always on Always on, app triggered
Protocol Support IPv4 and IPv6 IPv6 Only IPv4 and IPv6
Traffic Filtering No No Yes
Azure AD Integration No No Yes
Modern Management Yes No (group policy only) Yes (MDM)
Clients must be domain-joined? No Yes No
Requires Microsoft Infrastructure No Yes No
Supports Windows 7 Yes Yes Windows 10 only

Always On VPN Hands-On Training

If you are interested in learning more about Windows 10 Always On VPN, consider registering for one of my hands-on training classes. More details here.

Additional Resources

Always On VPN and the Future of Microsoft DirectAccess

5 Important Things DirectAccess Administrators Should Know about Windows 10 Always On VPN

3 Important Advantages of Windows 10 Always On VPN over DirectAccess

Enabling Secure Remote Administration for the NetMotion Mobility Console

During the initial setup of a NetMotion Mobility gateway server, the administrator must choose to allow either Secure (HTTPS) or Non-secure (HTTP) connections when using the web-based Mobility Console.

Enabling Secure Remote Administration for the NetMotion Mobility Console

Configuring HTTPS

Security best practices dictate HTTPS should be enabled to protect credentials used to log on to the gateway remotely. Immediately after selecting the Secure (https:) option, the administrator is prompted to enter server certificate information. Enter this information and click OK to continue and complete the rest of the configuration as necessary.

Enabling Secure Remote Administration for the NetMotion Mobility Console

Self-Signed Certificate

When logging in to the Mobility console, the administrator is presented with a certificate error indicating there is a problem with the website’s security certificate. This is because the certificate is self-signed by the NetMotion Mobility gateway server and is not trusted.

Enabling Secure Remote Administration for the NetMotion Mobility Console

PKI Issued Certificate

The recommended way to resolve this is to request a certificate from a trusted certification authority (CA). To do this, open the Mobility Management Tool on the Mobility gateway server and click on the Web Server tab.

Enabling Secure Remote Administration for the NetMotion Mobility Console

Click on the Server Certificate button and then click New in the Certificate Request section.

Enabling Secure Remote Administration for the NetMotion Mobility Console

In the SAN (subject alternative name) field of the Optional Extension section enter the Fully Qualified Domain Name (FQDN) of the server using the syntax dns:fqdn. Include both the FQDN and the single-label hostname (short name) separated by a comma to ensure both names work without issue. For example:

dns:nm1.lab.richardhicks.net,dns:nm1

Enabling Secure Remote Administration for the NetMotion Mobility Console

Before requesting a certificate from a CA, the root and any intermediate CA certificates must first be imported. Click the Import button next to each, as required.

Enabling Secure Remote Administration for the NetMotion Mobility Console

Click Copy in the Certificate Request section to copy the Certificate Signing Request (CSR) to the clipboard and then save it to a text file. Now submit the CSR to be signed by the CA using the certreq.exe command. Open an elevated command or PowerShell window and enter the following commands.

certreq.exe -attrib “CertificateTemplate:[TemplateName]” -submit [Path_to_CSR_file]

For example:

certreq.exe -attrib “CertificateTemplate:LabWebServer” -submit certreq.txt

Select a CA from the list and click OK, then save the certificate response when prompted.

Enabling Secure Remote Administration for the NetMotion Mobility Console

Enabling Secure Remote Administration for the NetMotion Mobility Console

Click Response and specify the location of the certificate response file saved in the previous step.

Enabling Secure Remote Administration for the NetMotion Mobility Console

Once complete, the newly issued certificate will be in place. Click Close to complete the process.

Enabling Secure Remote Administration for the NetMotion Mobility Console

Click Yes when prompted to restart the Mobility console.

Enabling Secure Remote Administration for the NetMotion Mobility Console

Trusted Certificate

Opening the Mobility Console no longer produces a certificate error message with a certificate installed from a trusted CA.

Enabling Secure Remote Administration for the NetMotion Mobility Console

In addition, if you followed the guidance above and included the single-label hostname in the SAN field, accessing the server using the short name will also work without issue.

Enabling Secure Remote Administration for the NetMotion Mobility Console

Summary

Always select the option to use HTTPS to ensure the highest level of security and protection of credentials when remotely administering a NetMotion Mobility gateway server. For optimal security and to provide the best user experience, use a certificate issued and managed by a trusted CA to prevent certificate errors when opening the Mobility console.

Additional Information

NetMotion Mobility as an Alternative to DirectAccess

NetMotion Mobility Device Tunnel Configuration

Comparing NetMotion Mobility and DirectAccess Part 1 – Security

Comparing NetMotion Mobility and DirectAccess Part 2 – Performance

DirectAccess and NetMotion Mobility Webinar

 

Always On VPN Protocol Recommendations for Windows Server Routing and Remote Access Service (RRAS)

Always On VPN Protocol Recommendations for Windows Server Routing and Remote Access Service (RRAS)Windows 10 Always On VPN is infrastructure independent and can be implemented using third-party VPN devices. It is not necessary to deploy any Windows servers at all to support an Always On VPN solution. However, in a recent blog post I outlined some compelling reasons to consider using Windows Server 2016’s Routing and Remote Access Service (RRAS) feature to terminate VPN connections. RRAS supports both modern and legacy VPN protocols, each with their own advantages and disadvantages. The choice of which protocols to support will be determined by many factors, but it is important to understand the capabilities of each to make an informed decision.

RRAS VPN Protocols

Windows RRAS supports the following VPN protocols.

  • Internet Key Exchange version 2 (IKEv2) – RFC7296
  • Secure Sockets Tunneling Protocol (SSTP) – Microsoft
  • Layer Two Tunneling Protocol over IPsec (L2TP/IPsec) – RFC2661
  • Point-to-Point Tunneling Protocol (PPTP) – RFC2637

There are pros and cons associated with each of these VPN protocols. Here’s a breakdown of each.

IKEv2

This IPsec-based VPN protocol is the preferred choice for most deployments. IKEv2 provides the best security and performance, with native features that enhance mobility. This latest version of IKE (v2) features streamlined messaging during connection establishment and enhanced session management that reduce protocol overhead and improve performance.

Advantages: Best security and performance.
Disadvantages: Firewalls may block required UDP ports.

SSTP

SSTP is an excellent alternative to IKEv2. It uses industry standard Transport Layer Security (TLS), making it widely accessible from most locations. It provides good security out of the box, but can be improved upon with additional configuration. SSTP lends itself well to load balancing, making it much easier to scale out than IKEv2. Optionally, TLS can be offloaded to an Application Delivery Controller (ADC) to reduce resource utilization on the RRAS server and further improve performance.

Advantages: Easy to configure with firewall friendly access.
Disadvantages: Not as secure IKEv2.

L2TP

While technically supported for Always On VPN, L2TP is a legacy VPN protocol that offers no real advantages over IKEv2. Its use is unnecessary and should be avoided.

Advantages: None.
Disadvantages: Firewalls may block required UDP ports.

PPTP

PPTP is considered an obsolete VPN protocol with many known security vulnerabilities. Its use should be avoided at all costs.

Advantages: None.
Disadvantages: Insecure.

Summary

Implementation best practices dictate that IKEv2 and SSTP be enabled to support Windows 10 Always On VPN connections when using Windows Server 2016 RRAS. The use of L2TP/IPsec and PPTP should be avoided. The combination of IKEv2 and SSTP will provide the best security and availability for remote workers. Clients that can establish IKEv2 VPN connections can take advantages of the security and performance benefits it provides. SSTP can be enabled as a fallback for clients that are unable to establish an IKEv2 connection due to restricted firewall access.

Always On VPN Hands-On Training

Interested in learning more about Windows 10 Always On VPN? Hands-on training classes are now forming. More details here.

Additional Resources

Frequently Asked Questions about Microsoft’s PPTP Implementation

Always On VPN and Windows Server Routing and Remote Access Services (RRAS)

Windows 10 Always On VPN and the Future of DirectAccess 

5 Things DirectAccess Administrators Should Know about Always On VPN 

3 Important Advantages of Windows 10 Always On VPN over DirectAccess 

Windows 10 Always On VPN Hands-On Training Classes

NetMotion Mobility Device Tunnel Configuration

NetMotion Mobility Device Tunnel ConfigurationIn its default configuration, NetMotion Mobility connections are established at the user level. In most cases this level of access is sufficient, but there are some common uses cases that require VPN connectivity before the user logs on. Examples include provisioning a new device to a user who has never logged on before, or to allow support engineers to connect to a remote device without requiring a user to log in first.

Infrastructure Requirements

To support NetMotion Mobility’s “unattended mode” (device tunnel) it will be necessary to deploy a Windows Server 2016 (or 2012R2) Network Policy Server (NPS). In addition, an internal private certification authority (CA) will be required to issue certificates to the NPS server and all NetMotion Mobility client computers.

Client Certificate Requirements

A certificate with the Client Authentication Enhanced Key Usage (EKU) must be provisioned to the local computer certificate store on all NetMotion Mobility clients that require a device tunnel (figure 1). The subject name on the certificate must match the fully qualified domain name of the client computer (figure 2). It is recommended that certificate auto enrollment be used to streamline the provisioning process.

NetMotion Mobility Device Tunnel Configuration

Figure 1. Computer certificate with Client Authentication EKU.

NetMotion Mobility Device Tunnel Configuration

Figure 2. Computer certificate with subject name matching the client computer’s hostname.

NPS Server Certificate Requirements

A certificate with the Server Authentication EKU must be provisioned to the local computer certificate store on the NPS server (figure 3). The subject name on the certificate must match the fully qualified domain name of the NPS server (figure 4).

NetMotion Mobility Device Tunnel Configuration

Figure 3. Computer certificate with Server Authentication EKU.

NetMotion Mobility Device Tunnel Configuration

Figure 4. Computer certificate with subject name matching the NPS server’s hostname.

NPS Server Configuration

Next install the NPS server role by running the following PowerShell command.

Install-WindowsFeature NPAS -IncludeMamagementTools

Once complete, open the NPS server management console and perform the following steps.

Note: Below is a highly simplified NPS configuration designed for a single use case. It is provided for demonstration purposes only. The NPS server may be used by more than one network access server (NAS) so the example policies included below may not work in every deployment.

  1. Expand RADIUS Clients and Servers.
  2. Right-click RADIUS clients and choose New.
  3. Select the option to Enable this RADIUS client.
  4. Enter a friendly name.
  5. Enter the IP address or hostname of the NetMotion gateway server.
  6. Click Verify to validate the hostname or IP address.
  7. Select Manual to enter a shared secret, or select Generate to create one automatically.
  8. Copy the shared secret as it will be required when configure the NetMotion Mobility gateway server later.
  9. Click OK.
    NetMotion Mobility Device Tunnel Configuration
  10. Expand Policies.
  11. Right-click Network Policies and choose New.
  12. Enter a descriptive name for the new policy.
  13. Select Type of network access server and choose Unspecified.
  14. Click Next.
    NetMotion Mobility Device Tunnel Configuration
  15. Click Add.
  16. Select Client IPv4 Address.
  17. Click Add.
  18. Enter the internal IPv4 address of the NetMotion Mobility gateway server.
  19. Click OK.
  20. Click Next.
    NetMotion Mobility Device Tunnel Configuration
  21. Select Access granted.
  22. Click Next.
    NetMotion Mobility Device Tunnel Configuration
  23. Click Add.
  24. Choose Microsoft: Protected EAP (PEAP).
  25. Click OK.
  26. Select Microsoft: Protected EAP (PEAP).
  27. Click Edit.
  28. Choose the appropriate certificate in the Certificate issued to drop down list.
  29. Select Secure password (EAP-MSCHAP v2).
  30. Click Remove.
  31. Click Add.
  32. Choose Smart Card or other certificate.
  33. Click OK.
  34. Select Smart Card or other certificate.
  35. Click Edit.
  36. Choose the appropriate certificate in the Certificate issued to drop down list.
  37. Click OK.
    NetMotion Mobility Device Tunnel Configuration
  38. Uncheck all options beneath Less secure authentication methods.
  39. Click Next three times.
  40. Click Finish.
    NetMotion Mobility Device Tunnel Configuration

Mobility Server Configuration

Open the NetMotion Mobility management console and perform the following steps.

  1. In the drop-down menu click Configure.
  2. Click Authentication Settings.
  3. Click New.
  4. Enter a descriptive name for the new authentication profile.
  5. Click OK.
  6. Expand Authentication.
  7. Select Mode.
  8. Select Unattended Mode Authentication Setting Override.
  9. From the Authentication mode drop-down box choose Unattended.
  10. Click Apply.
    NetMotion Mobility Device Tunnel Configuration
  11. Expand RADIUS: Device Authentication.
  12. Select Servers.
  13. Select [Profile Name] Authentication Setting Override.
  14. Click Add.
  15. Enter the IP address of the NPS server.
  16. Enter the port (default is 1812).
  17. Enter the shared secret.
  18. Click OK.
    NetMotion Mobility Device Tunnel Configuration
  19. In the drop-down menu click Configure.
  20. Click Client Settings.
  21. Expand Device Settings.
  22. Select the device group to enable unattended mode for.
  23. Expand Authentication.
  24. Select Settings Profile.
  25. Select [Device Group Name] Group Settings Override.
  26. In the Profile drop-down menu choose the authentication profile created previously.
  27. Click Apply.
    NetMotion Mobility Device Tunnel Configuration

Validation Testing

If everything is configured correctly, the NetMotion Mobility client will now indicate that the user and the device have been authenticated.

NetMotion Mobility Device Tunnel Configuration

Summary

Enabling unattended mode with NetMotion Mobility provides feature parity with DirectAccess machine tunnel and Windows 10 Always On VPN device tunnel. It ensures that domain connectivity is available before the user logs on. This allows users to log on remotely without cached credentials. It also allows administrators to continue working seamlessly on a remote computer after a reboot without having a user present to log on.

Additional Resources

NetMotion Mobility as an Alternative to DirectAccess

 

DirectAccess IP-HTTPS Null Cipher Suites Not Available

DirectAccess IP-HTTPS Null Cipher Suites Not AvailableMicrosoft first introduced support for null cipher suites for the IP-HTTPS IPv6 transition technology in Windows Server 2012, and it is supported for DirectAccess in Windows 8.x and Windows 10 clients. Using null cipher suites for IP-HTTPS eliminates the needless double encryption that occurs when using encrypted cipher suites. DirectAccess is a unique workload where SSL/TLS encryption isn’t really required because the payload being transported in HTTPS is already encrypted.

No Encryption by Design

When supporting Windows 8.x and Windows 10 clients, ensuring null cipher suites (TLS_RSA_WITH_NULL_SHA and TLS_RSA_WITH_NULL_SHA256) are enabled and operational is crucial to providing the highest levels of performance and scalability for the remote access solution. When following implementation best practices, this isn’t really an issue. However, in some cases null cipher suites may be disabled. This will result in reduced scalability and degraded performance for Windows 8.x and Windows 10 clients.

Validating SSL/TLS Configuration

The easiest way to verify that null cipher suites are being offered by the DirectAccess server is to use the Qualys SSL Labs server test site. Ideally you should see a result similar to this.

DirectAccess IP-HTTPS Null Cipher Suites Not AvailableFigure 1. Qualys SSL Labs server test site results for properly configured DirectAccess server.

Don’t be alarmed by the overall rating “F”. That happens because the Qualys test site is designed to test web servers where using null cipher suites would be a serious security issue. As I stated previously, the DirectAccess workload is unique in that its HTTPS payload is already encrypted, so using null cipher suites is acceptable in this scenario.

DirectAccess IP-HTTPS Null Cipher Suites Not AvailableFigure 2. Qualys SSL Labs server test site results for properly configured DirectAccess server showing support for null SSL/TLS cipher suites.

Null Cipher Suites Missing

When performing the Qualys SSL labs server test on a DirectAccess server, an overall rating of “A” is not desirable and indicates the DirectAccess server is misconfigured. This is caused by the lack of support for null cipher suites.

DirectAccess IP-HTTPS Null Cipher Suites Not AvailableFigure 3. Qualys SSL Labs server test site results for misconfigured DirectAccess server.

Common Causes

Null cipher suites for SSL and TLS can be disabled for a variety of reasons. Below are some of the most common causes for the lack of support for null cipher suites for DirectAccess.

Self-Signed Certificates – Using the Getting Started Wizard (simplified deployment) will configure DirectAccess using a self-signed certificate for IP-HTTPS. Using a self-signed certificate is discouraged for numerous reasons, most importantly because it disables support for null cipher suites.

Security Hardening – Security administrators may proactively disable support for null cipher suites in a misguided effort to “improve security” for DirectAccess. While this is acceptable and recommended on a web server, it is not advisable to disable null cipher suites on a DirectAccess server.

SSL Certificate Signing Algorithm – Using an SSL certificate signed with an Elliptical Curve (EC) key as opposed to an RSA key will result in the loss of support for null cipher suites for IP-HTTPS. High security/assurance certificates signed with EC keys are not recommended for use on DirectAccess servers and should be avoided if possible.

DirectAccess Configuration Options – Enabling One-Time Password (OTP) authentication on the DirectAccess server will also result in a loss of support for null cipher suites. Also, adding additional roles to the DirectAccess server such as client-based VPN or the Web Application Proxy (WAP) can also result in null cipher suites being disabled.

Summary

Null cipher suites are implemented by design on DirectAccess servers to enhance performance for Windows 8.x and Windows 10 clients and improve overall scalability for the implementation. They eliminate the pointless double encryption of DirectAccess communication, which itself is already encrypted. For optimal performance and scalability, be sure to follow implementation best practices and use a PKI-managed (public or private) SSL certificate signed with an RSA key (SHA-256 recommended). Resist the urge to “harden” the DirectAccess server by disabling support for null cipher suites, and avoid the use of SSL certificates signed with EC keys. In addition, carefully consider DirectAccess deployment options such as OTP authentication and consider deploying roles such as VPN and WAP on a separate server.

Additional Information

DirectAccess IP-HTTPS SSL and TLS Insecure Cipher Suites

DirectAccess IP-HTTPS Null Encryption and SSTP VPN

DirectAccess and FIPS Compliant Algorithms for Encryption

SSL Certificate Considerations for DirectAccess IP-HTTPS 

 

 

Always On VPN Windows 10 Device Tunnel Step-by-Step Configuration using PowerShell

Always On VPN Windows 10 Device Tunnel Step-by-Step Configuration using PowerShellWindows 10 Always On VPN and DirectAccess both provide seamless, transparent, always on remote network access for Windows clients. However, Always On VPN is provisioned to the user, not the machine as it is with DirectAccess. This presents a challenge for deployment scenarios that require the VPN connection to be established before the user logs on. To address this issue, Microsoft introduced support for a device tunnel configuration option beginning with Windows 10 version 1709 (Fall creators update).

Want to learn more about Windows 10 Always On VPN? Register for one of my hands-on training classes now forming in cities across the U.S. Details here.

Prerequisites

To support an Always On VPN device tunnel, the client computer must be running Windows 10 Enterprise or Education version 1709 (Fall creators update). It must also be domain-joined and have a computer certificate with the Client Authentication Enhanced Key Usage (EKU) issued by the organization’s Public Key Infrastructure (PKI).

Always On VPN Windows 10 Device Tunnel Step-by-Step Configuration using PowerShell

In addition, only the built-in Windows VPN client is supported for Always On VPN device tunnel. Although Windows 10 Always On VPN user connections can be configured using various third-party VPN clients, they are not supported for use with the device tunnel.

VPN ProfileXML

The Always On VPN device tunnel is provisioned using an XML file. You can download a sample VPN ProfileXML file here. Make any changes required for your environment such as VPN server hostnames, routes, traffic filters, and remote address ranges. Optionally include the trusted network detection code, if required. Do not change the protocol type or authentication methods, as these are required.

Always On VPN Windows 10 Device Tunnel Step-by-Step Configuration using PowerShell

Reference: https://docs.microsoft.com/en-us/windows-server/remote/remote-access/vpn/vpn-device-tunnel-config#configure-the-vpn-device-tunnel

Once the ProfileXML file is created, it can be deployed using Intune, System Center Configuration Manager (SCCM), or PowerShell. In this post I’ll cover how to configure Windows 10 Always On VPN device tunnel using PowerShell.

Client Configuration

Download the PowerShell script located here and then copy it to the target client computer. The Always On VPN device tunnel must be configured in the context of the local system account. To accomplish this, it will be necessary to use PsExec, one of the PsTools included in the Sysinternals suite of utilities. Download PsExec here, copy it to the target machine, and then run the following command in an elevated PowerShell command window.

PsExec.exe -i -s C:\windows\system32\WindowsPowerShell\v1.0\powershell.exe

Always On VPN Windows 10 Device Tunnel Step-by-Step Configuration using PowerShell

Another elevated PowerShell window will open, this one now running in the context of the local system account. In this window, navigate to the folder where you copied the PowerShell script and XML file to. Run the PowerShell script and specify the name of the ProfileXML file, as shown below.

VPN_Profile_Device.ps1 -xmlFilePath .\profileXML_device.XML -ProfileName DeviceTunnel

Always On VPN Windows 10 Device Tunnel Step-by-Step Configuration using PowerShell

To verify creation of the VPN device tunnel, run the following PowerShell command.

Get-VpnConnection -AllUserConnection

Always On VPN Windows 10 Device Tunnel Step-by-Step Configuration using PowerShell

Note: Be advised that the ConnectionStatus is always Disconnected. Hopefully this will be addressed by Microsoft in the near future.

Server Configuration

If you are using Windows Server 2012 R2 or Windows Server 2016 Routing and Remote Access Service (RRAS) as your VPN server, you must enable machine certificate authentication for VPN connections and define a root certification authority for which incoming VPN connections will be authenticated with. To do this, open an elevated PowerShell command and run the following commands.

$VPNRootCertAuthority = “Common Name of trusted root certification authority”
$RootCACert = (Get-ChildItem -Path cert:LocalMachine\root | Where-Object {$_.Subject -Like “*$VPNRootCertAuthority*” })
Set-VpnAuthProtocol -UserAuthProtocolAccepted Certificate, EAP -RootCertificateNameToAccept $RootCACert -PassThru

Always On VPN Windows 10 Device Tunnel Step-by-Step Configuration using PowerShell

Summary

Once the Always On VPN device tunnel is configured, the client computer will automatically establish the connection as soon as an active Internet connection is detected. This will enable remote logins for users without cached credentials, and allow administrators to remotely manage Always On VPN clients without requiring a user to be logged on at the time.

Additional Information

Configure Windows 10 VPN Device Tunnel on Microsoft.com

3 Important Advantages of Always On VPN over DirectAccess

5 Things DirectAccess Administrators Should Know About Always On VPN 

Windows 10 Always On VPN and the Future of DirectAccess

Windows 10 Always On VPN Training and Consulting Services

DirectAccess and FIPS Compliant Algorithms for Encryption

DirectAccess administrators may be required to enable Federal Information Processing Standards (FIPS) compliant algorithms for encryption, hashing, and signing on DirectAccess servers to meet certain regulatory and compliance requirements.

DirectAccess and FIPS Compliant Algorithms for Encryption

Performance Impact

Be advised that enabling this setting will disable support for null cipher suites for the IP-HTTPS IPv6 transition technology. This will result in the double encryption of all DirectAccess client communication, which will increase resource consumption on DirectAccess servers. This leads to reduced scalability and degraded performance for all DirectAccess clients, including Windows 8.x and Windows 10.

If enabling FIPS compliant cannot be avoided, additional compute capacity (CPU and memory) should be provisioned. For best results, add additional servers to distribute the workload and improve performance for DirectAccess clients.

Always On VPN

If you’re looking for better security and performance, consider migrating to Windows 10 Always On VPN. Always On VPN fully supports FIPS compliant algorithms without the negative performance impact associated with DirectAccess. If you’d like to learn more about security and Always On VPN, fill out the form below and I’ll get in touch with you.

Additional Resources

Always On VPN and the Future of DirectAccess 

5 Things DirectAccess Administrators Should Know About Always On VPN 

3 Important Advantages of Always On VPN over DirectAccess 

3 Important Advantages of Always On VPN over DirectAccess

3 Important Advantages of Always On VPN over DirectAccess Windows 10 Always On VPN hands-on training classes now forming. Details here.

Windows 10 Always On VPN provides seamless and transparent, always on remote network access similar to DirectAccess. The mechanics of how it is delivered and managed are fundamentally different, as I discussed here. Some of these changes will no doubt present challenges to our way of thinking, especially in the terms of client provisioning. However, Always On VPN brings along with it some important and significant advantages too.

No More NLS

A Network Location Server (NLS) is used for inside/outside detection by DirectAccess clients. By design, the NLS is reachable by DirectAccess machines only when they are on the internal network. NLS availability is crucial. If the NLS is offline or unreachable for any reason at all, DirectAccess clients on the internal network will mistakenly believe they are outside the network. In this scenario, the client will attempt to establish a DirectAccess connection even though it is inside. This often fails, leaving the DirectAccess client in a state where it cannot connect to any internal resources by name until the NLS is brought back online.

Always On VPN eliminates the frailty of NLS by using the DNS connection suffix for trusted network detection. When a network connection is established, an Always On VPN connection will not be established if the DNS connection suffix matches what the administrator has defined as the internal trusted network.

Full Support for IPv4

DirectAccess uses IPv6 exclusively for communication between remote DirectAccess clients and the DirectAccess server. IPv6 translation technologies allow for communication to internal IPv4 hosts. While this works for the vast majority of scenarios, there are still many challenges with applications that do not support IPv6.

Always On VPN supports both IPv4 and IPv6, so application incompatibility issues will be a thing of the past! With full support for IPv4, the need for IPv6 transition and translation technologies is eliminated. This reduces protocol overhead and improves network performance.

Infrastructure Independent

3 Important Advantages of Always On VPN over DirectAccess Windows servers are required to implement DirectAccess. Always On VPN can be implemented using Windows servers as well, but it isn’t a hard requirement. Always On VPN is implemented entirely on the Windows 10 client, which means any third-party VPN device can be used on the back end, including Cisco, Checkpoint, Juniper, Palo Alto, Fortinet, SonicWALL, F5, strongSwan, OpenVPN, and others! This provides tremendous deployment flexibility, making it possible to mix and match backend infrastructure if required. For example, a Windows RRAS VPN server with Palo Alto and SonicWALL firewalls could all be implemented at the same time (using the Windows built-in VPN client). Importantly, making changes to VPN infrastructure is much less impactful and disruptive to clients in the field. VPN devices can be upgraded, replaced, and moved internally without requiring corresponding policy changes on the client.

Additional Information

Always On VPN and the Future of Microsoft DirectAccess 

5 Things DirectAccess Administrators Should Know about Always On VPN 

Contact Me

Have questions about Windows 10 Always On VPN? Interested in learning more about this new solution? Fill out the form below and I’ll get in touch with you.

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