On-Demand Branch Office (VPN with Windows Server 2003)

  • Article

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

The Portland and Dallas branch offices of Electronic, Inc. are connected to the corporate office by using on-demand site-to-site VPN connections. Both the Portland and Dallas offices contain a small number of employees who only need occasional connectivity with the corporate office. The Windows Server 2003 routers in the Portland and Dallas offices are equipped with an ISDN adapter that dials a local Internet service provider to gain access to the Internet, and then a site-to-site VPN connection is made across the Internet. When the VPN connection is idle for five minutes, the routers at the branch offices terminate the VPN connection.

The Dallas branch office uses the IP network ID of 192.168.28.0 with a subnet mask of 255.255.255.0 (192.168.28.0/24). The Portland branch office uses the IP network ID of 192.168.4.0 with a subnet mask of 255.255.255.0 (192.168.4.0/24).

To simplify the configuration, the VPN connection is a one-way initiated connection that is always initiated by the branch office router. For more information, see the topic titled One-way Initiated Demand-Dial Connections in Windows Server 2003 Help and Support.

Figure 3 shows the Electronic, Inc. VPN server that provides on-demand branch office connections.

Art Image

Figure 3: The Electronic, Inc. VPN server that provides on-demand branch office connections

To deploy on-demand site-to-site VPN connections to connect the Portland and Dallas branch offices to the corporate office based on the settings configured in the Common Configuration for the VPN server section of this paper, the following additional settings are configured.

Domain Configuration

For the VPN connection to the Dallas office, the user account VPN_Dallas is created with the following settings:

  • Password of nY7W{q8~=z3.

  • For the account properties of the VPN_Dallas account, the User must change password at next logon option is cleared and Password never expires option is selected.

  • For the dial-in properties on the VPN_Dallas account, the remote access permission is set to Control access through Remote Access Policy and the static route 192.168.28.0 with a subnet mask of 255.255.255.0 is added.

  • The VPN_Dallas account is added to the VPN_Routers group.

For the VPN connection to the Portland office, the user account VPN_Portland is created with the following settings:

  • Password of P*4s=wq!Gx1.

  • For the account properties of the VPN_Portland account, the User must change password at next logon option is cleared and Password never expires option is selected.

  • For the dial-in properties on the VPN_Portland account, the remote access permission is set to Control access through Remote Access Policy and the static route 192.168.4.0 with a subnet mask of 255.255.255.0 is added.

  • The VPN_Portland account is added to the VPN_Routers group.

Remote Access Policy Configuration

To define the authentication and encryption settings for the VPN routers, the following remote access policy is created:

Policy name: VPN Routers

Access method: VPN

User or Group Access: Group with the EXAMPLE\VPN_Routers group selected

Authentication Methods: Extensible Authentication Protocol with the Smart card or other Certificate type and Microsoft Encrypted Authentication version 2 (MS-CHAP v2) selected

Policy Encryption Level: Strong encryption and Strongest encryption selected

The following sections describe a PPTP-based on-demand branch office connection for the Dallas office and an L2TP/IPSec-based on-demand branch office connection for the Portland office.

PPTP-based On-Demand Branch Office

The Dallas branch office is a PPTP-based branch office that uses a Windows Server 2003 router to create an on-demand, site-to-site VPN connection with the VPN server in New York as needed. When the connection is made and is idle for five minutes, the connection is terminated.

To deploy a PPTP, one-way initiated, on-demand, site-to-site VPN connection to the corporate office based on the settings configured in the Common Configuration for the VPN Server and On-Demand Branch Office sections of this paper, the following settings are configured on the Dallas router.

Demand-Dial Interface for the Connection to the ISP

To connect the Dallas office router to the Internet by using a local ISP, a demand-dial interface is created using the Demand-Dial Interface wizard with the following settings:

  • Interface Name: ISP

  • Connection Type: Connect using a modem, ISDN adapter, or other physical device

  • Select a Device: The appropriate ISDN device is selected.

  • Phone Number: Phone number of the ISP for the Dallas office.

  • Protocols and Security: The Route IP packets on this interface check box is selected.

  • Static Routes for Remote Networks

    To create the connection to the Dallas ISP when the site-to-site VPN connection needs to be made, the following static route is configured:

    Destination: 207.46.130.1

    Network mask: 255.255.255.255

    Metric: 1

  • Dial Out Credentials

    User name: Dallas office ISP account name

    Password: Dallas office ISP account password

    Confirm password: Dallas office ISP account password

To run the Demand-Dial Interface wizard, right-click Network Interfaces, and then click New Demand-Dial Interface.

Demand-Dial Interface for Site-to-Site VPN Connection

To connect the Dallas office router to the VPN server by using a site-to-site VPN connection over the Internet, a demand-dial interface is created by using the Demand-Dial Interface wizard with the following settings:

  • Interface Name: CorpHQ

  • Connection Type: Connect using virtual private networking (VPN)

  • VPN Type: Point to Point Tunneling Protocol (PPTP)

  • Destination Address: 207.46.130.1

  • Protocols and Security: The Route IP packets on this interface check box is selected.

  • Static Routes for Remote Networks

    To make all locations on the corporate intranet reachable, the following static route is configured:

    Destination: 172.16.0.0

    Network mask: 255.240.0.0

    Metric: 1

    To make all locations on Electronic, Inc. branch offices reachable, the following static route is configured:

    Destination: 192.168.0.0

    Network mask: 255.255.0.0

    Metric: 1

  • Dial Out Credentials

    User name: VPN_Dallas

    Domain: electronic.example.com

    Password: nY7W{q8~=z3

    Confirm password: nY7W{q8~=z3

L2TP/IPSec-based On-Demand Branch Office

The Portland branch office is an L2TP/IPSec-based branch office that uses a Windows Server 2003 router to create an on-demand, site-to-site VPN connection with the VPN server in New York as needed. When the connection is made and is idle for five minutes, the connection is terminated.

To deploy an L2TP/IPSec, one-way initiated, on-demand, site-to-site VPN connection to the corporate office based on the settings configured in the Common Configuration for the VPN Server and On-Demand Branch Office sections of this paper, the following settings are configured on the Portland router:

Certificate Configuration

The Portland router was configured by the Electronic, Inc. network administrator while it was physically connected to the Electronic, Inc. intranet and then shipped to the Portland site. While the Portland router was connected to the Electronic, Inc. intranet, a computer certificate was installed through autoenrollment.

Demand-Dial Interface for the Connection to the ISP

To connect the Portland office router to the Internet by using a local ISP, a demand-dial interface is created by using the Demand-Dial Interface wizard with the following settings:

  • Interface Name: ISP

  • Connection Type: Connect using a modem, ISDN adapter, or other physical device

  • Select a Device: The appropriate ISDN device is selected.

  • Phone Number: Phone number of the ISP for the Portland office.

  • Protocols and Security: The Route IP packets on this interface check box is selected.

  • Static Routes for Remote Networks

    To create the connection to the Portland ISP when the site-to-site VPN connection needs to be made, the following static route is configured:

    Destination: 207.46.130.1

    Network mask: 255.255.255.255

    Metric: 1

  • Dial Out Credentials

    User name: Portland office ISP account name

    Password: Portland office ISP account password

    Confirm password: Portland office ISP account password

Demand-Dial Interface for Site-to-Site VPN Connection

To connect the Portland office router to the VPN server by using a site-to-site VPN connection over the Internet, a demand-dial interface is created by using the Demand-Dial Interface wizard with the following settings:

  • Interface Name: CorpHQ

  • Connection Type: Connect using virtual private networking (VPN)

  • VPN Type: Layer 2 Tunneling Protocol (L2TP)

  • Destination Address: 207.46.130.1

  • Protocols and Security: The Route IP packets on this interface check box is selected.

  • Static Routes for Remote Networks

    To make all locations on the corporate intranet reachable, the following static route is configured:

    Destination: 172.16.0.0

    Network mask: 255.240.0.0

    Metric: 1

    To make all locations on Electronic, Inc. branch offices reachable, the following static route is configured:

    Destination: 192.168.0.0

    Network mask: 255.255.0.0

    Metric: 1

  • Dial Out Credentials

    User name: VPN_Portland

    Domain: electronic.example.com

    Password: P*4s=wq!Gx1

    Confirm password: P*4s=wq!Gx1