Chapter 6 - Installing And Configuring Remote Access Service

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This chapter describes how to install Windows NT Remote Access Service (RAS) on your computer and how to configure the service to work on your network. (Note: It assumes that Windows NT has already been successfully installed on your computer.)

RAS can be installed during the initial Setup or after the initial Windows NT Setup is complete.


To install and configure RAS, you must be logged on as a member of the Administrators group.

Hardware Requirements for RAS

Before you install RAS, all hardware should be installed and working. Depending on your network and requirements, you might need the following hardware:

  • Network adapter card with a certified Network Driver Interface Specification (NDIS) driver 

  • One or more compatible modems (see the Hardware Compatibility List or the Remote Access Setup program) and an available COM port 

  • Multiport adapter card for acceptable performance with multiple remote connections 

  • X.25 smart card (if using an X.25 network) 

  • ISDN card or modem (if using an ISDN line)

See the Hardware Compatibility List to verify the compatibility of all hardware in a Windows NT computer.

Choosing Modems

To ensure that your modems work with Remote Access Service, select them from the list of supported modems in the Hardware Compatibility List. Microsoft has tested and verified these modems with Remote Access Service.

Compatibility and Speed

Modems from different manufacturers—and even different models from one manufacturer—might be incompatible in some settings and circumstances. Even modems that claim to follow the Hayes AT command set might, at times, be unable to communicate with other Hayes-compatible modems.

And because modems achieve high speeds in different ways, compatibility problems increase with high-speed modems. Even modems that follow a standard for compression and error correction might be unable to communicate with each other at higher speeds and, therefore, might fall back to a slower speed. So, if you buy high-speed modems from different manufacturers to benefit from high data-exchange rates, you might be disappointed.

Note To ensure compatibility, have clients and servers use the same kind of modem. This is less critical if your modems conform to industry standards, but still it is safer to choose the same model for both clients and server. For more information on RAS and modem compatibility standards, see the RAS Reference appendix in the Networking Guide of the Windows NT Server Resource Kit version 4.0.

For rates of 12,000 bps and higher, modem manufacturers often require that computer-to-modem communication occur at 19,200 bps. For this reason, Remote Access software assumes that modems able to connect at 12,000 or 14,400 bps can function at the computer-to-modem speeds of 19,200 bps or faster. Virtually all high-speed modems can do so.

Supported Modems

Modems supported by Remote Access do not necessarily work in all modes with other modems in the list. For example, the Hayes® V-Series 9600 modem connects at 9600 bits per second (bps) only with another Hayes V-Series 9600 modem. So if you install this modem on a Remote Access server, make sure that Remote Access clients also have Hayes V-Series 9600 modems. Otherwise, connections will probably be made at 2400 bps.

If you use one of the modems named in the Hardware Compatibility List when you set up Remote Access, and you cannot connect, follow these steps:

To troubleshoot a supported modem 

  1. Make sure your cabling is correct. (See Appendix B, "RAS Cabling.") 

  2. If you still cannot connect, check the modem's documentation to verify that the modem has been correctly installed. 

  3. Using a terminal emulator program (such as Windows NT HyperTerminal), try to issue commands to the modem. See the procedure "To test a modem with Windows NT HyperTerminal" in this chapter. 

  4. Turn on device logging in the Registry by changing the following key to 1: 

    HKEY_LOCAL_MACHINE \SYSTEM \CurrentControlSet \Services \RASMan \Parameters \Logging. 

For more information, see Chapter 8, "Maintenance and Troubleshooting."

Unsupported Modems

Although modems not supported by Microsoft can work with the Remote Access Service, they have not yet been tested with the software. If you choose unsupported modems, make sure they support one of the modulation schemes shown in Table 2.1.

Table 2.1 shows the most popular modulation schemes in the left column and their corresponding speed range in bits per second (bps) in the right column.

Popular Modulation Schemes

Modem to Modem speed

V.22 (ITU-T (formerly CCITT) Standard)

1200 bps

V.22 bis (ITU-T (formerly CCITT) Standard)

2400 bps

V.32 (ITU-T (formerly CCITT) Standard)

4800 - 9600 bps

V.32 bis (ITU-T (formerly CCITT) Standard)

4800 - 14400 bps

V.fc and (Proprietary Modulation Schemes)

2400 - 28800 bps

V.34 (ITU-T (formerly CCITT) Standard)

2400 - 28800 bps

For details about industry standard protocols, see the glossary in online Help.

When configuring an unsupported modem for RAS, you must select from the list of supported modems a modem that matches yours as closely as possible. For best results, compare entries in the MODEM.INF file with commands for your modem (located in your modem's documentation).

To see a list of supported modems, you can also have RAS try to autodetect your modem.

To configure an unsupported modem 

  1. In Control Panel, click Network. 

  2. In the Services tab, select Remote Access Service

  3. Click Properties

  4. In the Remote Access Setup dialog box, select the port you want to configure for the unsupported modem, and click Add

  5. In the Add RAS Device dialog box, click Install Modem

  6. In the RAS Setup Wizard, select the checkbox to select a modem from a list of supported modems. 

  7. From the list of modems, select the one that is most similar to your modem. 

  8. Click Next, and continue with the Setup Wizard. 

  9. If you configure a new port for the unsupported modem, restart your computer.

    If you reconfigure a port already in use, you do not need to restart your computer, but you do need to stop and then restart RAS.

If you have trouble connecting through an unsupported modem, test the modem's compatibility.

To test a modem's compatibility 

  1. Check the modem's documentation to make sure you have installed and configured the modem correctly. 

  2. Make sure your modem is connected to a serial communication (COM) port on your computer and that your software is set for the same port. 

  3. Turn on your modem. 

  4. Check to see if the modem works properly with Windows NT HyperTerminal.

    (For instructions, see the following procedure.) If the test works, you can assume the modem is not malfunctioning. 

  5. If the modem fails to work after you have verified that it works with Windows NT HyperTerminal, contact the manufacturer and request a modem command file compatible with the RAS Modem.inf file. 

    For information about creating a correct modem command file, see "Adding a New Modem to Modem.inf" in Appendix C, "Understanding MODEM.INF." 

To test a modem with Windows NT HyperTerminal 

  1. From the Accessories folder, click the HyperTerminal folder and select HyperTerminal. 

  2. In the Connection Description dialog box, enter any name in the Name box and click OK.

  3. In the Connect To dialog box, click Cancel

    Note HyperTerminal tests the first modem listed in the Connect Using box. 

  4. In the HyperTerminal window, type at. 

    Your modem should return OK, which is echoed on the screen. Some modems return 0, depending on their result code settings. 

  5. If your modem will not work through HyperTerminal, call the manufacturer. 

Connecting Without a Modem

To establish a direct serial connection between two computers, select a null modem. Although a direct serial connection eliminates the need for a network adapter card, it is a slow link, and password authentication is still required. A null modem configuration works best only for computers physically near each other.

To configure your system for a direct serial connection 

  • Select a null modem from the list of modems during setup when configuring the COM ports for a serial connection.

    A null modem must be configured on both the client and the server.

For information about configuring COM ports for RAS usage, see "Installing Remote Access Software" in this chapter. For information about installing ports, see the Ports icon in Control Panel.

Important For information about cabling required for null modems, see Appendix B, "RAS Cabling" or see the topic "Cabling Requirements" in the RAS online Help.

Modem-Pooling Equipment

Windows NT works with a variety of third-party modem pooling equipment.

To configure a server to work with modem-pooling equipment 

  1. Configure the equipment to behave like one of the modem types listed in the Setup program. (In other words, the modem-pooling equipment must generate and accept command strings as if it were a modem of the chosen type.) The switching equipment must also have the same RS-232 signal behavior as the specified modem. 

  2. Connect COM ports to this equipment, and specify the modem type in the Remote Access Setup program.

    Microsoft suggests that the equipment be configured as a Hayes-compatible modem, a widely-known standard. 

Installing Remote Access Software

Although RAS is part of Windows NT Setup, you can also install it using the Network icon in Control Panel after you have installed Windows NT.

Note RAS installation will vary slightly, depending on which network protocols are installed. If you will use the TCP/IP or IPX protocol with RAS, install the protocol before you install RAS. (Note that selecting an uninstalled protocol will cause that protocol to be installed at the conclusion of RAS Setup.) For information about installing either protocol, see the Windows NT Server Start Here.

To add the Remote Access software 

  1. In Control Panel, click the Network icon. 

  2. In the Services tab, click Add

  3. From the Network Service box, select Remote Access Service and then click OK

    When prompted for the path to the distribution files, provide the path and click OK. The RAS files will be copied to your computer. 

  4. If you have no devices installed on your computer, the Modem Wizard appears and helps you install a RAS capable device. 

  5. The Add RAS Device dialog box displays a list of all ports available to Windows NT for RAS. If you have successfully installed a multiport adapter, ISDN card, X.25 card, or other device, it will appear in this list. 

    Select the port you will use for remote access, and click OK

  6. Click Install Modem to have RAS Setup automatically detect the modem connected to the selected port. 

    If RAS Setup cannot distinguish between two or more modems, a dialog box will appear, requiring you to select your modem from a short list. 

  7. Click Install x.25 Pad to install an x.25 Pad. 

  8. In the Remote Access Setup dialog box, select the port and click Configure

    In the Configure Port Usage box, choose how the port is to be used and click OK. 

    • Dial out only means the computer will be a RAS client only. 

    • Receive calls only means the computer will be a RAS server only. 

    • Dial out and Receive calls means the computer can be a client or server. (Note: The computer cannot be both at the same time.) 

  9. In the Remote Access Setup dialog box, configure RAS network-wide settings by clicking Network. For more information, see the following section, "Choosing a Protocol for a RAS Server." 


  10. Consult the following table for a description of each button in the Remote Access Setup dialog box. Default settings are usually ideal.


  11. Click Continue when you are finished setting up the port and network configurations. 

    RAS Server Configuration dialog boxes will appear for the protocols installed on your computer. See the appropriate topics in the following section for configuring LAN protocols for RAS use. 

  12. Click Close in the Confirmation dialog box, and click OK in the Network dialog box.

    You might be prompted to confirm network protocols or other settings. 

  13. You must restart your computer for the Remote Access installation and configuration take effect. 

The Remote Access software includes the following applications:

  • Dial-Up Networking is the client version of RAS and is used to connect to dial-up servers. The Dial-Up Networking icon is located in the My Computer dialog box and in the Accessories folder on the Start menu. 

  • Dial-Up Networking Monitor, used to monitor connections and devices, is located in Control Panel. 

  • Remote Access Admin, used to monitor remote users connecting to a RAS server, is located in the Administrative Tools folder on the Start menu.

Choosing a Protocol for a RAS Server

Because RAS provides access to a LAN, you must select and configure the protocols to use on the LAN. A Windows NT Workstation or Server computer can be either a RAS server or a client. You must configure the LAN protocols RAS will use in each role.

A RAS computer's role is determined when you specify how RAS-enabled ports will be used. See the previous procedure for information on the various port settings.

Setting network LAN protocols affect all RAS operations for all RAS-enabled ports. For example, you must enable TCP/IP for the LAN before you can choose to use TCP/IP for a specific RAS entry. For more information on choosing protocols for RAS entries, see the section "Choosing a Protocol for a RAS Entry" later in this chapter.

For information about choosing a LAN protocol, see "Configuring RAS to Use LAN Protocols" in Help.

Configuring a RAS Server to Use NetBEUI

NetBEUI gives the best performance for NetBIOS applications in small LANs. Removing NetBEUI still allows you to use RAS with TCP/IP or IPX. You can configure whether NetBEUI clients can access the entire network or the RAS computer only.

For information about using NetBEUI on a RAS server, see "Configuring a RAS Server to Use NetBEUI" in Help.

Configuring a RAS Server to Use TCP/IP

Use the Network icon in Control Panel to configure or reconfigure the TCP/IP settings for RAS connections.

The RAS server has two TCP/IP configurations:

  • Its own basic configuration and IP address as a server on the LAN. For information on this configuration, see the TCP/IP Help file. 

  • Its RAS configuration to supply IP addresses to RAS clients.

For information about how to configure RAS to supply IP addresses to RAS clients, see "Configuring a RAS Server to Use TCP/IP" in Help.

Configuring Name Resolution for RAS Clients

RAS client name resolution is based on the available network services and on the RAS server configuration:

If the RAS server is configured to use a WINS server and a DNS server on the network, RAS clients will use them as well.If the RAS server has multiple network adapter cards, clients will use the WINS servers on the first network configured for INS and DNS.Note Clients can also specify addresses of WINS and DNS servers on a per-entry basis by configuring TCP/IP Settings in the Dial-Up Networking Server tab.RAS clients in small networks where IP addresses do not change can use a HOST file and LMHOSTS file for name resolution. Using these files on the local drive saves transmitting the name resolution request to the WINS server and waiting for a response over the modem.

Note Standard broadcast name resolution does not work over RAS. Users must have a name resolution method, such as WINS or a LMHOSTS file, or they must use IP addresses.

For more information about name resolution on a Microsoft TCP/IP network, see Chapter 3, "Implementation Considerations."

Configuring a RAS Server to Use IPX

Use the Network icon in Control Panel to configure or reconfigure the IPX settings for RAS connections. For information about using IPX on a RAS server, see "Configuring a RAS Server to Use IPX" in Help.

Choosing a Protocol for a RAS Entry

Dial-Up Networking clients can enter and maintain names and telephone numbers of remote networks. Clients connect to and disconnect from remote networks using the Dial-Up Networking program. Users can select the network protocols to use for a specific Phonebook entry, depending on the type of server you are dialing (PPP, SLIP, or Microsoft RAS).

For information about choosing a protocol on a RAS client, see "Choosing a Protocol for a RAS Entry" in Help.

Special Configurations

This section contains information about configuring RAS in special situations and using specialized hardware.

Configuring Stand-alone Remote Servers to Appear to Local Network Browsers

Users who set up a RAS server at home and dial into it from a computer at work must follow the referenced procedure to have the name of their home server appear in the browsing list of remote clients.

For information about configuring a remote RAS server to appear to local network browsers, see "Configuring Stand-alone Remote Servers to Appear to Local Network Browsers" in Help.

Configuring Other Vendors' Dial-Up Servers for NetBIOS IP and IPX

If Windows NT clients dialing into other vendors' dial-up servers must access NetBIOS resources using IP and IPX, the dial-up servers must be configured to forward NetBIOS broadcast traffic. Such forwarding might result in poor performance over the RAS connection if the LAN has substantial NetBIOS activity. For information about configuring a server to forward NetBIOS broadcasts, see "IPXRouter Parameters" in Appendix A, "RAS Registry Values."

For better performance on TCP/IP networks, Windows NT clients can use WINS servers or proxies when dialing into other vendors' servers if the server can provide access to a Windows NT Server WINS server or proxy agent on the LAN.For more information, see TCP/IP online Help.

Granting Remote Access Permissions

After installing Remote Access software on a server, you must grant Remote Access permissions to users. Without them, users cannot successfully connect to the Remote Access computer (even if Remote Access client software is installed on their computers).

For more information see "Setting Up RAS Security on Accounts," in Chapter 7 "RAS Security."

Dialing Options

Windows NT RAS features several new dialing options such as AutoDial and Multilink. With these options you can automatically connect to remote sites and resources and use multiple WAN devices to connect to the same remote resource, thereby increasing bandwidth.

RAS Automatic Dialing

RAS AutoDial maps and maintains network addresses to RAS phonebook entries, allowing them to be automatically dialed when referenced—whether from an application or from the command line. A network address can be an Internet host name, an IP address, or a NetBIOS server name.

AutoDial also learns about every connection made over a RAS link for possible automatic reconnection later.

There are two possible scenarios when AutoDial attempts to make a connection:

  • If you are disconnected from a network, AutoDial attempts to create a network connection whenever an application references a remote address. 

  • If you are connected to a network, AutoDial attempts to create a network connection for only those addresses that it has previously learned. Incorrectly typed server or Internet host names will not cause an AutoDial attempt.

Although AutoDial is automatically enabled when you start your computer, you can turn it off if desired. (For example, you might have multiple Internet providers on a computer at one location and want to use different providers at different times).

To turn off AutoDial 

  1. In Dial-Up Networking, select an entry to dial from the Phonebook list.

  2. Click More and select User preferences

  3. In the Dialing tab, click to clear each location listed in the Enable auto-dial by location list.

You can turn on AutoDial by reselecting a location in the Enable auto-dial by location list.

Known Problems for this Release
  • AutoDial does not yet work over IPX connections. AutoDial works only with the TCP/IP and NetBEUI protocols. In Dial-Up Networking, select the entry for each RAS connection over which you expect to AutoDial. Then click More and select Edit Entry and Modem Settings. In the Server tab, click to clear the IPX/SPX compatible check box. 

  • If you need to disable your network card, you cannot simulate being disconnected from the network by simply unplugging the cable from the network adapter card. Instead, create a new hardware profile with your network adapter card disabled:

    In the System icon in Control Panel, in the Hardware Profiles tab, make a copy of your original installation. Then, in the Devices icon, select your network card and click HW Profiles. Select the new hardware profile and disable your network card. When you reboot, you can choose this no-network profile.

    This is useful if you have a portable computer with a PCMCIA network card installed all the time and you want to connect to the network from a remote location.

    If the following three conditions exist, make sure your DNS server does not resolve Internet hostnames:

    • a DNS server on your network 

    • your network is not directly connected to the Internet 

    • you want to AutoDial Internet addresses

    Most Internet utilities (ftp, www browsers, etc.) do not ask DNS for exact matches, and it is possible for the DNS server to successfully resolve an address to one within your local domain. For example, try typing a similar command at the Command Prompt while connected to your network: 

    C:> ping 

    Bad IP address 

    If the ping command resolves the name to an IP address, you must disable DNS on your computer for AutoDial to automatically dial Internet addresses when connected to your network.

  • AutoDial requires at least one TAPI dialing location. AutoDial can automatically dial different RAS phonebook entries for the same address, depending on the current TAPI dialing location.

    For example, suppose two TAPI dialing locations are created (Home and Office), and suppose you run the command ftp AutoDial automatically dials the RAS phonebook entry INTERNET1 when your current TAPI dialing location is set to Home, and it automatically dials the RAS phonebook entry INTERNET2 when your current TAPI dialing location is set to Office.

    To create TAPI dialing locations, use the Telephony icon in Control Panel.

  • When Explorer is initializing, it might reference remote paths in your desktop shortcut icons or targets which, in turn, will cause an AutoDial attempt. If AutoDial tries to create a connection when you log on to your computer, either delete remote paths from your Desktop shortcut icons or targets, or change them to reference a local file. 

  • If commands in your Explorer Start/Run list access remote paths, selection of one causes an AutoDial attempt. Currently, you cannot selectively delete items in this list. But to work around this issue, remove the HKCU\Software\Windows\CurrentVersion\Explorer\RunMRU key in the Registry, log out, and log back on again. Your Explorer Start/Run list should now be empty.

  • The Registry configuration for AutoDial has changed. It is recommended that you delete the Autodial registry key in: 

    HKEY_CURRENT_USER \Software \Microsoft \RAS 

    AutoDial will then relearn your addresses. 

Troubleshooting AutoDial

If you have problems, run the following command from the Command Prompt to give basic AutoDial status:

C:> rasautou -s 

Status ouptput has two parts: network adapter card bindings and a list of learned AutoDial addresses. At least one network adapter card binding must be reported as working for AutoDial to realize you are connected to the network. For AutoDial to automatically create a network connection while you are connected to a network, the address must be in the list of learned AutoDial addresses. Here is an example listing network adapter card bindings and a list of learned addresses:

Checking netcard bindings...
NetworkConnected: network (\Device\Nbf_IEEPRO1, 0) is up

Enumerating AutoDial addresses...
There are 3 Autodial addresses:

Multilink Dialing

Multilink combines multiple physical links into a logical "bundle." This aggregate link increases your bandwidth.

RAS performs PPP Multilink dialing over multiple ISDN, X.25, or modem lines. The feature is available only if multiple WAN adapters are available on the computer.

To use Multilink, both the clients and servers must have Multilink enabled.

Note If a client uses a multinked phonebook entry to dial a server that is configured to call that user back for security reasons (enforced callback), then only one of the multilinked devices will be called back. This is because only one number can be stored in a user account. Therefore, only one device will connect and all other devices will fail to complete the connection, and the client loses multilink functionality.

A situation that will work is if the multilinked phonebook entry is ISDN with two channels that have the same phone number.

To enable Multilink on a RAS client

  1. In Dial-Up Networking select an entry to dial from the Phonebook list.

  2. Click More and select Edit entry and modem properties

  3. In the Basic tab, in the Dial using box, select multiple lines. 

  4. Click Configure to choose which modems or adapters to use for the connection and then click OK

For more information about Multilink connection options, see the online Help.

To enable Multilink on a RAS server

  1. In Control Panel, click the Network icon. 

  2. In the Services tab, select Remote Access Service in the Network Services box and click Properties

  3. In the Remote Access Setup dialog box, click Network

  4. In the Network Configuration dialog box, select Enable Multilink and click OK

Monitoring Connections

The Dial-Up Networking Monitor (located in the Control Panel) provides the status of a call, and allows you to see

  • the speed at which you connected 

  • the duration of the connection

  • the names of users connected to a RAS server 

  • protocols used during the connection 

  • which devices are part of a connection

For more information on using Dial-Up Monitor, see Chapter 8, "Maintenance and Troubleshooting."