RASPPPOE PPP over Ethernet Protocol for Windows NT 4.0

RASPPPOE

PPP over Ethernet Protocol

for Windows NT 4.0

Contents

1. Introduction

2. Installing the PPP over Ethernet Protocol

3. Creating PPP over Ethernet Dial-Up Connections

4. Removing the PPP over Ethernet Protocol

5. Advanced Protocol Features

6. Troubleshooting

7. Known Issues

8. Revision History

9. Contacting the Author

1. Introduction

Welcome to RASPPPOE, a PPP over Ethernet (short: PPPoE) implementation for Windows 95, 98, 98SE, ME, NT 4.0, 2000, XP and .NET. PPPoE as a method for establishing PPP connections through Ethernet adapters is described in RFC 2516 and is used by many broadband service providers to allow authentication and maintain the familiar 'dial-up experience' when connecting to the Internet through a broadband modem. Although there are other PPPoE implementations for Windows, this one still has its unmatched strong points:

Seamless integration into the operating system. This protocol makes Ethernet network adapters appear as 'modems', allowing PPPoE to be easily used within the standard Dial-Up Networking framework.

Compatibility: This protocol supports Internet Connection Sharing (including on-demand dialing), power management (Standby and Hibernate) as well as multiprocessor systems.

Completeness: This protocol can not only act as a PPPoE Host (client), but also as an Access Concentrator (server), fully implementing RFC 2516.

Compactness: The complete protocol is less than 250 KB. Yet no concessions were made in the implementation.

To install this protocol, please follow the installation instructions carefully. If you have problems using it, see Troubleshooting for help. If you are successfully using this protocol, you can check if you find any of the advanced features useful. You may also want to know about the known issues. Users upgrading from a previous version of this protocol should check the Revision History to find out what changed. If you want to get in touch with me, see Contacting the Author.

- Robert Schlabbach

License and Disclaimer

This driver, installation files and documentation is all Copyright (C) 2000-2002 by Robert Schlabbach. All rights reserved. It is distributed without any warranty. Use at your own risk. You may use and copy it complete and unmodified free of charge for non-commercial purposes only. Commercial exploitation, redistribution for commercial purposes, especially redistribution by Internet service providers as 'their' service to their customers, is strictly prohibited. Internet service providers must purchase a license for distribution to their customers. The licensed version additionally features an installer, which typically requires no reboot (except on Windows NT 4.0) and leads the user to the first login for an 'instant success' customer experience. For licensing details please contact:

Monzoon Networks AG
Hardstrasse 235
CH-8005 Zurich
Switzerland

e-mail: raspppoe@monzoon.net
Web: https://www.monzoon.net

2. Installing the PPP over Ethernet Protocol

ATTENTION: RASPPPOE requires Service Pack 4 or later for operation on Windows NT 4.0. If you are currently using an older or no Service Pack, please update your operating system with the latest Service Pack available.

NOTE: During installation, you may be asked for Windows NT files. If possible, specify the location of the Service Pack you had applied. This will save you the step of having to re-apply the Service pack after installation of this protocol.

WARNING: You are about to install a driver. Since any driver installation poses a non-zero risk of crashing your operating system, and since you need to restart your computer to complete this installation anyway, you are advised to save your work and close all running applications before proceeding.

Since you are about to install a driver, you will need administrative privileges to perform the installation. If you are logged on to a user account, log off and log on to an account with administrative privileges before proceeding.

If there is already a different PPPoE implementation installed on your machine, it might get confused by the PPPoE traffic generated by this protocol. This protocol was written to peacefully coexist with other PPPoE implementations on the same machine, but other programmers may not have been as thoughtful. Thus, it is recommended (but not required!) that you uninstall any other PPPoE implementations and reboot your machine before proceeding.

If you already have a previous version of this PPP over Ethernet Protocol installed, you must first remove the old version. See Removing the PPP over Ethernet Protocol for details.

Unpack the downloaded archive to a temporary installation directory. Make sure that the following files are correctly extracted: README9X.HTM, READMENT.HTM, README2K.HTM, NETPPP95.INF, RASPPP95.INF, WINPPPOE.INF, OEMSETNT.INF, NETPPPOE.INF, RASPPPOE.INF, WINPPPOE.DLL, RASPPPOE.DLL, RASPPPOE.EXE, RASPPPOE.SYS and RMSPPPOE.SYS. The Intel Itanium 64-bit CPU release only contains the files README2K.HTM, NETPPPOE.INF, RASPPPOE.INF, RASPPPOE.DLL, RASPPPOE.EXE and RMSPPPOE.SYS. NOTE: Explorer may be configured to hide DLL and SYS files, so it may not display these files.

Right-click the Network Neighborhood icon on your desktop and select Properties to bring up the Network window.

Click on the Protocols tab.

On the Protocols property sheet, click the Add button.

In the Select Network Protocol window, click the Have Disk button.

In the Insert Disk window, type the full path of your temporary folder. Then click the OK button. A new window opens, offering the PPP over Ethernet Protocol for installation. Click OK to start installing the protocol.

During installation, you may be asked for Windows NT files. If possible, specify the location of the Service Pack you had applied. If you specify the location of the original Windows NT files, you will have to re-apply the Service Pack after the installation of the protocol.

Back at the Network window, click on the Bindings tab.

On the Bindings property sheet, select Show Bindings for: all adapters.

If you have a network adapter dedicated to your broadband modem, it is recommended that you disable the bindings to all other components and leave only PPP over Ethernet Protocol bound. To do this, double-click the dedicated network adapter in the list to expand it and right-click each unneeded component below it and select Disable. After you are done, all components below that adapter except the PPP over Ethernet Protocol should have a little stop sign next to them.

If you have more than one network adapter in your system, you may want to disable the PPP over Ethernet Protocol for all adapters but the one your broadband modem is actually connected to. To do this, double-click each network adapter in the list you want to disable the protocol for, right-click the PPP over Ethernet Protocol item below it and select Disable.

Click on the Close button to close the Network window and restart your computer to make the protocol functional. After the reboot, you need to create a dial-up connection to use it. See the next section for details.

IMPORTANT: If you were prompted for Windows NT files during the installation and you specified the location of the original Windows NT files, you will first have to re-apply the latest Service Pack after the restart and then restart your computer again to make the protocol functional.

3. Creating PPP over Ethernet Dial-Up Connections

If you installed the protocol with the automated installer, it already created a dial-up connection for you. If you installed the protocol manually, you can create a PPP over Ethernet dial-up connection with the Dial-Up Connection Setup application provided with the protocol, which creates dial-up connections with all the correct settings at the click of a button.

Click the Start button on the taskbar and select Run to bring up the Run dialog box.

Type RASPPPOE in the edit field and click the OK button to run the Dial-Up Connection Setup application.

If the application quits with an error message, follow the advice it gives.

A dialog box comes up with a combo box labeled Query available PPP over Ethernet Services through Adapter: at the top. Select the network adapter your broadband modem is connected to from the list. If the protocol is only operating on one network adapter, the box will be grayed out as there is no choice to make.

Generally, it is recommended that you create a connection for an adapter, not for a specific service, so that it continues to work even if your service provider changes the server or service name. To do this, simply click the Create a Dial-Up Connection for the selected Adapter button now. Shortly afterwards, a shortcut to the new dial-up connection named Connection through Adapter Name should show up on your desktop.

If you want to create a connection for a specific service, click the Query Available Services button. The application will send out a query for offered services and display the result in the list view below. If an error message is displayed, see Troubleshooting for help. Otherwise, select the desired service and the button below will change to Create a Dial-Up Connection for the selected Service. Click the button to create a connection for this service. Shortly afterwards, a shortcut to the new dial-up connection named Connection to Service Name at Access Concentrator or Connection to Access Concentrator (if the connection is for the default service) should show up on your desktop.

After you have created the connection(s) you need, click the Exit button to quit the application.

Double-click the desktop icon for the dial-up connection you created to bring up the Dial-Up Networking window.

In the Dial-Up Networking window, click on the Dial button.

In the Connect to Connection Name window, enter your user name and password if your service provider requires authentication.

Click on the OK button. If all goes well, you should be connected to the Internet almost instantly. If not, see Troubleshooting.

4. Removing the PPP over Ethernet Protocol

WARNING: You are about to remove a driver. Since any driver removal poses a non-zero risk of crashing your operating system and since you need to restart your computer to complete the removal anyway, you are advised to save your work and close all running applications before proceeding.

Since you are about to remove a driver, you will need administrative privileges to perform the removal. If you are logged on to a user account, log off and log on to an account with administrative privileges before proceeding.

First, you may want to remove all dial-up connections you created for connecting through this protocol. To do so, double-click the My Computer icon on your desktop, and then the Dial-Up Networking icon in the upcoming window. Select each of the dial-up connections you created for this protocol under Phonebook entry to dial:, then click on the More button, select Delete entry and confirm. If you had created any shortcuts to these dial-up connections on your desktop, right-click them and select Delete as well.

Right-click the Network Neighborhood icon on your desktop and select Properties to bring up the Network window.

Click on the Protocols tab.

On the Protocols property sheet, select PPP over Ethernet Protocol and click the Remove button.

A dialog box comes up asking you to confirm the removal. Make sure that you are really about to uninstall the PPP over Ethernet Protocol and click Yes.

Back at the Network window, click Close to close the window. You will be prompted to restart your computer. After the restart, the protocol is completely removed from your computer.

Note: If you do not have any other dial-up devices in your machine, the Remote Access Service will bring up an error message when closing the Network window, saying it is incorrectly configured. Also, you will get a notification that a service was unable to start upon each restart of your computer. If you do not intend to use Dial-Up Networking for the time being, you can fix this by re-opening the Network window, going to the Services tab, selecting Remote Access Service, clicking the Remove button and confirming. Note that the Remote Access Service can be reinstalled later should you need it again.

5. Advanced Protocol Features

This section covers the advanced features of the protocol. Average users should be perfectly happy with the default settings, although specifying the link speed to display may be of interest. Users having problems with VPN software might try if overriding the MTU reported by the protocol helps. Users with flat rate Internet access may be interested in making the connection 'always on'. If you are interested in using the protocol's server capability, please see Enabling the protocol to act as a PPPoE Access Concentrator.

To bring up the protocol settings for an adapter:

Right-click the Network Neighborhood icon on your desktop and select Properties to bring up the Network window.

Click on the Protocols tab, select PPP over Ethernet Protocol in the list and click the Properties button.

In the PPP over Ethernet Protocol Properties window, select the network adapter the protocol settings of which you wish to modify under Configure PPP over Ethernet Protocol on Adapter:.

Changes to the protocol settings take effect when you close the PPP over Ethernet Protocol Properties window with the OK button unless noted otherwise.

The General tab offers the following settings:

5.1 Limit TCP MSS Maximum Segment Size (MSS) Option

When using an Internet Connection Sharing or Network Address Translation (NAT) application to share the the Internet access in a LAN, the client machines are completely unaware of the packet size restrictions imposed by the nature of PPP over Ethernet (in contrast to e.g. modem or ISDN connections, which allow passing arbitrarily sized packets). Typically, a client assumes that packets of up to 1500 bytes can be passed and thus indicates a Maximum Segment Size of 1460 bytes (1500 bytes minus 40 bytes for the TCP and IP headers) when opening a TCP session, resulting in either side of the connection sending packets up to 1500 bytes in size, too large to pass through a PPP over Ethernet connection, which can only pass packets up to 1492 bytes in size. These oversized packets are then often silently dropped at either side of the PPP over Ethernet connection, leading to delays or hangs when accessing the Internet from a client.

To work around this problem, this option makes the protocol scan all network packets it sends and receives for the TCP Maximum Segment Size (MSS) option and, if a value greater than either the default (1492) or the overridden MTU minus 40 for the IP and TCP headers (i.e. 1452 in case of the default MTU) is found, change it to this value, recalculate the TCP checksum and pass the modified packet. This option is enabled by default. If you are not using Internet Connection Sharing or Network Address Translation (NAT), you can disable this option to save a little (very little) CPU power, although leaving it enabled has no negative side effects.

5.2 Override Maximum Transfer Unit

By default, the protocol will report an MTU of 1492 bytes, the maximum possible for PPP over Ethernet. However, you can use this option to override the MTU initially reported by the protocol. Making the protocol initially report a lower MTU was found to help with certain VPN software packages which 'blindly' add their own overhead without paying any respect to the MTU reported by the driver, making the network packets too large to pass through a PPP over Ethernet connection. Check the Override Maximum Transfer Unit checkbox and type the MTU the protocol should report in the Maximum Transfer Unit (MTU) edit box. The valid range is 576 through 1492 bytes. Reducing the MTU by 32 bytes to 1460 should generally suffice to make misbehaved VPN software work. Note: Regardless of this setting, the protocol will always send and receive packets of up to 1492 bytes. Only the MTU initially reported by the protocol (the MaxFrameSize value in response to the OID_WAN_GET_INFO request) and, if enabled, the TCP MSS option limit are affected by this setting.

For any changes to this setting to take effect, you need to restart your computer.

NOTE: This option will only 'stick' if you enter an MTU other than 1492. If you only check the checkbox, but leave the MTU at 1492, the protocol will recognize the default value and clear the checkbox the next time you open the properties dialog, because the MTU was not actually overridden.

5.3 Number of lines (WAN endpoints)

The protocol is capable of running several simultaneous PPP over Ethernet sessions through one adapter. This feature will probably be very rarely - if ever - needed. To allow this, you can configure the number of WAN endpoints (dial-up devices) the protocol exposes for a network adapter. The default is 1, and up to 10 WAN endpoints can be configured. This setting requires you to restart your computer to take effect.

The Advanced tab offers the following settings:

5.4 Specify Link Speed

By default, the protocol will report the speed of the network adapter you are connecting through as the speed of a dial-up connection you make through it, as it cannot find out the actual speed of your broadband modem. However, you can specify the connection speed the protocol should report for connections through a specific adapter. To do this, check the Specify Link Speed checkbox and type the link speed the protocol should report in the Link Speed (kbps) edit box, in kilobits per second. If you want to revert to displaying the adapter's link speed, clear the Specify Link Speed checkbox. Note: This setting has absolutely no effect on the network traffic through this adapter; it is purely a cosmetic setting. This setting takes effect the next time you establish a PPP over Ethernet connection.

5.5 Event Logging options

The protocol can inform you about informational events, warnings and errors during operation by logging events to the System event log. By default, the protocol logs all types of events, which should result in no log entries during flawless operation. If you find the event log flooded with repeated entries despite flawless operation, you can disable logging that type of event by clearing the corresponding checkbox. Clearing all checkboxes prevents the protocol from logging any events.

Log Informational Events will log any vendor-specific information received.

Log Warnings will log non-fatal warnings that do not necessarily prevent successful operation.

Log Errors will log fatal errors that prevent correct function of the protocol.

You use Event Viewer to view any events logged by this protocol:

Click on the Start button, select Programs, then Administrative Tools (Common) and finally Event Viewer.

Click on Log and select System. Look for log entries from source RMSPPPOE there.

To get a detailed description of a logged event, double click the event in the view on the right-hand side.

NOTE: If you are using another PPP over Ethernet software on the same machine, you will find the event log flooded with Warnings from source RMSPPPOE that it received a PPPoE packet for an unknown session. To fix this, either use solely this protocol on the machine, or disable the Log Warnings option as described above.

Beyond these settings, the protocol offers the following possibilities:

5.6 Making a dial-up connection 'always on'

Users who enjoy flat rate Internet access may find it desirable to turn their connection into an 'always on' connection that is established once when the machine boots (before any user logs in) and kept until the machine is shut down. To make your dial-up connection 'always on', follow these steps:

If your service provider requires authentication, make sure you have saved the password by checking the Save Password checkbox in the Connect to Connection Name window and connecting at least once.

Obtain a tool which allows you to run an application as a service, e.g. the SRVANY tool from the Windows NT Resource Kit and create a service which runs the command line 'RASPHONE.EXE -d 'Connection Name'' (note the spelling!).

Alternatively, if you cannot obtain such a tool, you can copy the dial-up connection shortcut to the Startup folder of the Start menu, which will, however, require you to log in once to establish the connection after the system has booted. To do this, right-click the Start button, select Explore, in the upcoming Explorer window, double-click the Programs folder, then drag the dial-up connection shortcut on your desktop with the right mouse button and drop it on the Startup folder and select Copy Here.

Finally, you need to make a little registry change to prevent Windows NT from disconnecting when a user logs on and off again:

Run REGEDIT and navigate to:

HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindows NTCurrentVersionWinlogon

Then right-click the right-hand pane, select New -> String Value, name the value KeepRasConnections and set it to 1.

Reboot. Windows NT will establish the connection automatically (or when you log in if you chose the alternative method) and keep it until you shut the machine down.

NOTE: The connection will not be properly terminated when shutting the machine down or rebooting. This can cause problems with service providers who take very long to detect such a dropped connection and limit the number of concurrent connections. See Known Issues for further details.

5.7 Addressing a specific Service and/or Access Concentrator

In most cases, there is no need to address a specific Service or Access Concentrator. But should you have a need to do so, you can use the phone number field of your dial-up connection to specify a Service, Access Concentrator or both. The following phone number formats are possible:

A.      Blank or '0': The protocol will connect to the default Service of the first Access Concentrator that replies to the connection request.

B.       'Service-Name': The protocol will connect to the first Access Concentrator that replies offering the requested Service.

C.       'Access-Concentrator': The protocol will connect to the default Service of the named Access Concentrator.

D.      'Access-ConcentratorService-Name': The protocol will connect to the requested Service of the named Access Concentrator.

The RASPPPOE application uses format A for the phone number if you create a connection for an adapter and format C or D if you create a connection for a specific service.

5.8 Enabling the protocol to act as a PPPoE Access Concentrator

The protocol is able to act as a PPPoE Access Concentrator (server). This feature can be used for testing purposes, but also offers a future potential for advanced provider services like instant messaging or instant e-mail even for users who are offline at the time a message is received. The server capability is fully integrated with the operating system's Remote Access Service component. No PPPoE-specific configuration is needed. The protocol uses the current Computer Name as the Access Concentrator Name and offers any Service Name requested by a client. Note that the protocol will not offer any services until you explicitly enable its dial-up devices to accept incoming connections. To do this, follow these steps:

Right-click the Network Neighborhood icon on your desktop and select Properties to bring up the Network window.

Click on the Services tab, select Remote Access Service in the list and click the Properties button.

Select the Port (from device RASPPPOE, of type PPPoE) which you want to accept incoming connections on and click the Configure button. Note: If you do not know which network adapter a port belongs to, check the properties of a dial-up connection you created for that network adapter. On the Basic tab under Dial using: you will find the name of the port in brackets after the network adapter name.

In the Configure Port Usage window, select either Receive calls only or Dial out and Receive calls and close the window with the OK button.

You may now want to click on the Network button to configure the protocols for the incoming connections, e.g. to define the IP addresses to use.

Close the Remote Access Setup window with the Continue button, then close the Network window with the Close button and confirm to restart your computer.

If you want to disable the server on a port again, simply set the port usage back to Dial out only.

NOTE: If there are any changes to the number of network adapters the protocol is bound to, or to the number of lines per any adapter, the port usage for all PPPoE ports will be reset to Dial out only and you will have to reconfigure any ports you had configured to accept incoming connections.

For further help on using the Remote Access Service, please refer to the operating system's documentation on this topic.

6. Troubleshooting

This section helps you with possible problems you might encounter during the installation and use of the protocol.

6.1 RASPPPOE application does not list the desired adapter

First, be aware that you can use this protocol only on Ethernet adapters. As PPP over Ethernet only works over Ethernet, the protocol will only bind itself to Ethernet adapters (NdisMedium802_3). Adapters that do not support this medium type (e.g. internal broadband modems that do not expose a standard Ethernet interface through their driver) are not supported by this protocol.

You should make sure that the adapter in question is properly installed:

Right-click the Network Neighborhood icon on your desktop to bring up the Network window, select the Adapters tab and check if the adapter in question is listed there.

Check if the adapter is correctly configured: Select it in the list and click the Properties button. Make sure the configuration matches the hardware settings.

If you changed any settings, close the Network window with the Close button, restart your computer, then re-run the RASPPPOE application and check whether the adapter is listed now.

If the adapter still does not show up, make sure that the protocol is bound to the adapter in question:

Right-click the Network Neighborhood icon on your desktop to bring up the Network window, click on the Bindings tab and select Show Bindings for: all adapters.

Double-click the adapter in question in the list to expand it and look for the component PPP over Ethernet Protocol. If it has a little stop sign next to it, right-click it and select Enable. If you find it already enabled, try disabling it, closing the Network window with the Close button, then re-enabling it.

If you changed any settings, close the Network window with the Close button and restart your computer.

After the restart the RASPPPOE application should list the desired adapter.

6.2 RASPPPOE application reports 'RASPPPOE - No Service Offers Received' when querying available services

This error message means that the protocol did not receive any response from your service provider. You should check the following things in order:

Check if your broadband modem has successfully established a link with its counterpart. Most DSL modems have a Sync LED on them which indicates this status. If your modem has such an LED and it indicates that the link is down, contact your service provider for assistance.

Right-click the Network Neighborhood icon on your desktop to bring up the Network window, select the Adapters tab and check if the network adapter your broadband modem is connected to is listed there.

Check if your network adapter is correctly configured: Select it in the list and click the Properties button. If your network adapter offers such settings, make sure that the correct Line Speed and duplex mode is selected (most DSL modems only support 10Mbps half duplex mode). If your network adapter has several connectors at the back, make sure the correct connector is selected, which is most likely Twisted Pair (TP).

Check that the cable connecting your broadband modem to your network adapter is properly attached and of the correct type. Note that broadband modems typically have a 'crossed' connector on them, so you will need a straight cable to connect it directly to a network adapter, while you need to use a crossed cable or use an uplink port to connect it to a hub or switch.

Check with your service provider whether they currently have a service outage.

6.3 Connection attempt fails with 'Error 678: There was no answer.'

First, you should check whether you can get any reply from your service provider with the Dial-Up Connection Setup application provided with the protocol:

Click the Start button on the taskbar and select Run to bring up the Run dialog box.

Type RASPPPOE in the edit field and click the OK button to run the Dial-Up Connection Setup application.

If the application quits with an error message, follow the advice it gives.

A dialog box comes up with a combo box labeled Query available PPP over Ethernet Services through Adapter: at the top. Select the network adapter your broadband modem is connected to from the list. If the protocol is only operating on one network adapter, the box will be grayed out as there is no choice to make.

Click the Query Available Services button. If an error message is displayed, continue here for further help.

If the list view shows one or more offered services and you had tried to connect to a specific Service and/or Access Concentrator, make sure the one you had tried to connect to is listed. If you find your service provider has changed the Service Name and/or the Access Concentrator name, simply create a new connection with the new name(s) or edit the Phone number field in your existing dial-up connection accordingly.

Click the Exit button to quit the application.

If you do not want to connect to a specific Service and/or Access Concentrator, make sure the Phone number field of your dial-up connection is really completely blank.

6.4 Connection attempt fails with 'Error 691: Access was denied because the user name and/or password was invalid on the domain.'

If this error occurs despite using a valid user name and password, this may mean that the service provider you are connecting with negotiates a lower MTU than the one configured on your machine, which leads to this confusing error message due to this known issue. To fix this, use the MTU override option to lower the MTU to e.g. 1400 and then try connecting again. If you can successfully connect with the lower MTU, you can try increasing the MTU again to the maximum value that still allows you to connect successfully.

6.5 Connection is successfully established, but some (or all) Internet websites do not load properly

This is usually a sign of an MTU problem. You should determine the Path MTU to the problem site(s) (Note: The method described here does not work with all servers. If you get no reply at all from a server or a number below 548, you cannot determine the Path MTU to this server):

Connect, open a Command Prompt and run

ping -f -l xxxx Address

Where Address is the name or IP address of the server you have problems accessing. For xxxx, start with 1464 and lower the number until you get a reply. Then add 28 to the highest number at which you get a reply. The result is the Path MTU.

Example: You start getting replies at ping -f -l 1372 Address. The Path MTU is 1372 + 28 = 1400 bytes in this case.

Normally, the Path MTU to all servers should be 1492. However, some service providers appear to have a configuration problem which reduces the Path MTU. If you determine a Path MTU lower than 1492 to several (or all) servers on the Internet, you should enable the MTU override option and set it to the Path MTU you determined. After that setting has taken effect, all sites with a Path MTU greater than or equal to the value you set should load properly.

6.6 The 'Override Maximum Transfer Unit' option does not remain checked

This option will only 'stick' if you enter an MTU other than 1492. If you only check the checkbox, but leave the MTU at 1492, the protocol will recognize the default value and clear the checkbox the next time you open the properties dialog, because the MTU was not actually overridden.

6.7 The System Event Log contains 'Received a PPPoE Session packet for an unknown session' warnings

This warning merely means that the protocol received a PPPoE packet it could not attribute to any of its connections and is usually not a sign of any malfunction. One possible cause of this is your service provider sending one more packets after the connection has been terminated. This can also be caused by using another PPPoE implementation on the same machine. In that case, the System Event Log may end up being flooded with these warnings. You can prevent this by disabling the Log Warnings checkbox in the protocol's Event Logging options.

7. Known Issues

This section documents known issues with the protocol.

7.1 RAS Autodial service does not work with RASPPPOE

The RAS Autodial service does not recognize the dial-up devices offered by RASPPPOE and thus will not automatically establish a connection through it. There is currently no workaround for this issue.

Background: The RAS Autodial service only recognizes dial-up devices of the types COM, ISDN, VPN and X.25. However, RASPPPOE uses a custom type, PPPoE, for its dial-up devices to avoid conflicts with existing modems, ISDN adapters, VPN software or X.25 adapters when autoconfiguring its dial-up devices without the RAS control panel.

7.2 PPP authentication fails when Access Concentrator requests a lower MTU

When the Access Concentrator being connected to requests a PPP MRU lower than the MTU configured in RASPPPOE, the PPP authentication will fail with error 691 (Access was denied because the user name and/or password was invalid on the domain.). To fix this, use the MTU override option to lower the MTU to a value less than or equal to the Access Concentrator's PPP MRU requested value.

Background: The cause of this issue is undetermined.

7.3 When a dial-up connection is made 'always on', it is not properly terminated when shutting the machine down or rebooting

When you configure a PPP over Ethernet dial-up connection to be 'always on', the connection will not be properly terminated when shutting the machine down or rebooting. This causes problems with service providers who take very long to detect such a dropped connection and limit the number of concurrent connections - after several reboots, you may find yourself to log on to your service provider for some time. To work around this problem, always disconnect your 'always on' connection manually before rebooting.

Background: Investigation revealed that the protocol receives no indication that the system is going down. Neither the MiniportHalt(), nor the ProtocolUnbindAdapter(), nor the ProtocolPnPEvent(), nor the ProtocolStatus() handler and not even a handler registered with the NdisMRegisterAdapterShutdownHandler() are called to indicate the shutdown. Thus, it is not possible for the protocol to terminate its open connections prior to the shutdown. This is apparently a shortcoming of Windows NT.

8. Revision History

n      Version 0.98, October 3rd, 2002

First release with Windows 95 and Windows NT 4.0 support! The Windows 95 version uses a different driver binary, while Windows NT 4.0 runs the same binary as Windows 98/98SE/ME/2000/XP/.NET.

Added: Windows 95 support. Requires Microsoft Dial-Up Networking Upgrade 1.2 or later on the original Windows 95 release (4.00.950). Figured out how to make the fragments of NDIS Intermediate driver support in NDIS.VXD version 4.00.1111 work and how to install the driver. Created two new INF files for installation and added installation support to WINPPPOE.DLL to install and remove virtual miniport instances as needed. Wrote function replacements for NDIS functions not available in Windows 95. Changed the functions NdisMIndicateStatus(), NdisMIndicateStatusComplete(), NdisMResetComplete(), NdisMWanIndicateReceive(), NdisMWanIndicateReceiveComplete() and NdisMWanSendComplete() from macros back to imports. Added NdisRecalculatePacketCounts() and NdisQueryPacket() macro invocations for compatible packet initialization. Added #ifdefs to the driver source so that the Windows 95 driver binary can be compiled from the same source.

Added: Windows NT 4.0 support. Requires Service Pack 4 or later. Also requires a reboot after installation since Windows NT cannot start NDIS miniports dynamically. Wrote a completely new OEMSETNT.INF installation script from scratch which installs and removes virtual miniports on demand and automatically initializes the RAS TAPI devices exposed by the driver without having to go through the RAS configuration panel. Added a standalone, exported WindowsNTControlPanel function to RASPPPOE.DLL which is invoked from OEMSETNT.INF for configuration of the protocol properties. Changed and expanded the TAPI provider portion of the driver for compatibility with Windows NT 4.0.

Fixed: In Windows 2000/XP/.NET, the protocol properties dialog could not retrieve the current protocol configuration if more than one line per adapter was configured. Fixed this by stripping the 'line X' suffix from the TAPI line name before the string comparison.

Fixed: In Windows 98/98SE/ME, the protocol properties did not allow specifying values greater than 3276 kbps for the Link Speed option due to improper 16/32-bit handling. Fixed this by cleaning up the string-to-integer conversion calls. Now link speeds up to 65535 kbps can be entered in Windows 95/98/98SE/ME.

Fixed: The MiniportQueryInformation() handler made a call to NdisUnicodeStringToAnsiString(), which is not allowed at the IRQL the handler may be invoked at. Fixed this by moving the call to the ProtocolBindAdapter() handler.

Changed: RASPPPOE.EXE now uses TAPI version 1.3 to communicate with the running protocol for compatibility with Windows 95.

Changed: RASPPPOE.EXE now changes the characters [ and ] to ( and ), respectively, and strips trailing space characters from the connection name when creating a dial-up connection for compatibility with Windows NT 4.0.

n      Version 0.97, August 23rd, 2001

Added: An application manifest for RASPPPOE.EXE to enable the Windows XP visual style in its user interface.

Changed: The self-deleting code in RASPPPOE.EXE (fully licensed version only) was changed from an x86 assembly routine to a CPU independent method that is also compatible with Windows XP.

Fixed: The IA64 version caused STOP errors due to data misalignment. Fixed this by padding data structures where possible and by using the UNALIGNED compiler macro where misalignment cannot be avoided.

n      Version 0.96, May 29th, 2001

First release with Intel Itanium 64-bit CPU support! The IA64 version is distributed in a separate archive for now.

Fixed: Some code paths in the ProtocolReceivePacket() handler returned a non-zero value, which would not return the received packet to the network adapter driver, eventually causing it to run out of packets, making unable to operate. Fixed this by ensuring all code paths return zero.

Changed: The watchdog timer that checks every ten seconds whether any packets have been received will now send up to three LCP Echo-Requests before terminating the connection. Thus, a connection loss will now be detected within 40 to 50 seconds. This should cure the disconnection problems a number of users have been suffering from due to the watchdog timer being a bit too sensitive for some service providers.

Changed: When connecting to the unnamed default service, the protocol will now connect to the first offered service, even if it is not unnamed. This enhances compatibility with service providers who are not fully RFC 2516 compliant

n      Version 0.95, December 29th, 2000

Added: A no-reboot installer (fully licensed version only) that installs, repairs or upgrades the protocol from a single, self-extracting executable, typically without requiring a reboot on any of the supported platforms. Additionally, it creates a dial-up connection and then prompts the user to connect to allow an 'instant success' experience. The protocol will be added to the list of installed programs in Add/Remove Programs in Control Panel for convenient and complete uninstallation. Optional command-line switches allow silent installation, upgrade and removal for licensees who wish to provide their own installer front-end.

Added: Server capability. If one of the dial-up devices exposed by the protocol is configured to accept incoming connections, the protocol will offer the unnamed default service on the corresponding adapter and use the computer name set in the networking configuration as the Access Concentrator name. If the connection is accepted, the protocol will do a left-to-right (big-endian) comparison of the adapter's MAC address with the one of the connecting host, and generate an even (LSB 0) session identifier is the adapter's MAC address is lower, or an odd (LSB 1) one if it is higher, to ensure that two machines connecting to each other simultaneously do not generate identical session identifiers. The server is not industry-strength. There is no limit on the connections per MAC address, nor is any encryption being used in the Access Concentrator Cookies generated by the protocol, so a malicious user on the same Ethernet segment could occupy all incoming lines with a denial-of-service attack, but do no harm beyond that. Great care has been taken to minimize the load on the system if such an attack is made.

Added: Timers. The protocol now times out connection requests and resends requests two times, once after one second, then after two seconds, and three seconds after that indicates no answer. Incoming connections are offered for five seconds before being rejected. When a connection is established, a watchdog timer checks every ten seconds whether any packets been received, and generates and sends an LCP Echo-Request to the peer if no packet has been received since the last check. If at the next check still no packet has been received, the connection is terminated with no answer. Thus, a connection that was dropped by the other end without proper termination will be detected as lost within 20 to 30 seconds.

Added: In Windows 98/98SE/ME, RASPPPOE.EXE now checks whether Dial-Up Networking is installed and gives an error message if it is not. Additionally, it checks if NDIS.VXD version 4.10.2222 is installed, and warns the user to install fix Q243199 if it is.

Added: In Windows 98/98SE/ME, WINPPPOE.DLL now adds a new value to the Packet Size setting of the Dial-Up Adapter called PPP over Ethernet, which sets the packet size to either the default (1492) or the overridden MTU.

Fixed: RASPPPOE.EXE would show erroneous query results if more than one Access Concentrator offered services, because the driver was returning an incorrect query result length. Fixed this by correcting the length calculation in the driver.

Fixed: In Windows 98/98SE/ME, RASPPPOE.EXE was unable to properly retrieve the names of network adapters which were 58 characters or more long, which led to it displaying a blank adapter name and being unable to create a dial-up connection for the adapter. Fixed this by increasing the size of the retrieval buffer and limiting the size of the passed name.

Fixed: Windows 98/98SE/ME was unable to tell apart the dial-up devices exposed for two network adapters of the same name. Fixed this by appending a '#X' suffix to the dial-up device name if the protocol is already bound to a network adapter of the same name.

Fixed: In Windows 98SE/ME, NDIS.VXD versions 4.10.2224 (from fix Q243199 for Windows 98SE) and 4.90.3000 (included in Windows ME) randomly dropped packets received from the NE2000 or the Realtek RTL8029(AS) driver without indicating them to the protocol for an unknown reason. Worked around this problem by adding NDIS_PACKET_TYPE_ALL_LOCAL to the packet filter if Windows 98/98SE/ME and one of these two drivers is detected, which makes NDIS.VXD work reliable again.

Fixed: If TAPI requested to drop a call, the protocol would not transition to the idle call state, because I had misunderstood a paragraph in the DDK documentation. This might also have been the cause of TAPISRV.EXE causing crashes in RPCRT4.DLL in Windows ME. Fixed this by reviewing all TAPI call state transitions and making sure the behavior is compliant with the DDK documentation.

Fixed: When running a repair or upgrade install on Windows 2000, the protocol could crash the operating system with a blue screen indicating that RASPPPOE.SYS was unloaded without canceling pending operations. Investigation revealed that Windows 2000 was trying to call the protocol's ProtocolPnPEventHandler() function after it had been unloaded, because the protocol had not been deregistered. Further investigation revealed that the ProtocolUnload() handler is never called in Windows 2000, which is not documented in the Windows 2000 DDK documentation. Fixed this by providing a DriverUnload() handler again to deregister the protocol, and by putting the pointer to this function directly into the driver object in DriverEntry() to omit the NdisMRegisterUnloadHandler() call, which is not available in Windows 98. The ProtocolUnload() handler is still provided for Windows 98/98SE/ME.

Changed: RASPPPOE.EXE now displays a different error message if the user tried to query available services through an adapter which line is already in use by an active PPPoE session, explaining that the user needs to disconnect that session to be able to query services.

Changed: If more than one WAN Endpoint is configured for a network adapter, 'Line X' suffixes will now be appended in Windows 2000 as well. Previously, they were only appended in Windows 98/98SE/ME.

Changed: In Windows 2000, the protocol no longer logs query results to the event log. RASPPPOE.EXE made this function obsolete.

Changed: Removed the NCF_NOT_USER_REMOVEABLE flag from the WAN miniport (PPP over Ethernet Protocol) INF file for Windows 2000, allowing manual removal of any miniport instances left behind in Device Manager.

Changed: Replaced the previously imported strncmp() and _strnicmp() kernel functions with inline functions. Removed the need for the _snwprintf() kernel function by generating the 'Line X' suffixes directly in the code.

Changed: During protocol initialization and shutdown, the MiniportQueryInformation(), MiniportSetInformation(), MiniportReset() and MiniportWanSend() handlers now return NDIS_STATUS_ADAPTER NOT_READY instead of NDIS_STATUS_FAILURE.

Changed: The protocol service name and the driver binary name were changed to RMSPPPOE and RMSPPPOE.SYS, respectively, to enhance compatibility with future Windows versions.

n      Version 0.94, May 17th, 2000

First release with Windows 98/98SE/ME support! No thanks to Microsoft's complete lack of documentation on NDIS intermediate drivers in Windows 98/98SE/ME.

Added: Windows 98/98SE/ME support. Figured out the INF format for NDIS intermediate drivers in Windows 98/98SE/ME and where WAN.TSP expects an NDIS intermediate driver's TAPI registry subkey to be located in the registry. Added a 16-bit Windows DLL (WINPPPOE.DLL) with an NDI procedure to create that registry subkey upon installation, set the Dial-Up Adapter's IPMTU registry parameter to the MTU for PPP over Ethernet (Windows 98/98SE/ME was found to ignore the maximum frame size returned by the driver) and offer the protocol properties GUI. Changed the driver unload function to ProtocolUnload(), since NdisMRegisterUnloadHandler() is not supported in Windows 98/98SE/ME. Removed the NdisIMAssociateMiniport() call from the DriverEntry() function, since that call is not supported in Windows 98.

Added: RASPPPOE.EXE user-mode application for easy dial-up connection setup.

Added: Limit TCP MSS Option to make MTU changes on Internet Connection Sharing client machines unnecessary. A new function scans all incoming and outgoing packets for the TCP Maximum Segment Size (MSS) option and, if necessary, limits it to either the default (1492) or the overridden MTU (see below) minus 40 for the IP and TCP headers (i.e. 1452 in case of the default MTU) and recalculates the TCP checksum.

Added: MTU Override option to override the MTU initially reported by the driver. If an override value is specified, it will be reported as the MaxFrameSize in response to the OID_WAN_GET_INFO request. In Windows 98/98SE/ME, the Dial-Up Adapter's IPMTU registry parameter is also set to the override value. It will furthermore be taken into account when limiting the TCP MSS option. Making the protocol initially report a lower MTU was found to help with certain VPN software packages which 'blindly' add their own overhead without paying any respect to the MTU reported by the driver.

Added: WAN Endpoints GUI option to easily change the number of dial-up devices exposed for a network adapter.

Fixed: Dial on demand in Windows 2000 never triggered a connection. Windows 2000 apparently only dials modems, ISDN and X.25 devices on demand. Changed the device type of the dial-up devices exposed by the protocol to ISDN to work around this bug.

Fixed: The protocol could lose one of its internal packets each time an NdisTransferData() call failed, until it would eventually be unable to receive any data. It appears that never actually happened to anyone, though.

Fixed: The PPPoE version and type fields were reversed in the declaration. As the current PPPoE version and type are both 1, this bug went unnoticed.

Changed: The protocol will now no longer log a warning to the event log if it receives a PADT packet for a session that does not exist (or no longer does).

Changed: The Event Logging Options now default to logging all types of events. This should now produce no log entries during flawless operation

n      Version 0.92, February 6th, 2000

Fixed: No data transfer possible after successfully establishing a connection. The protocol was corrupting data packets it had to retrieve through NdisTransferData(). I had made the incorrect assumption that NdisTransferData() would use the ByteOffset parameter on the destination buffer as well, but instead it just starts at offset zero in the first buffer chained to the passed packet. Fixed this by chaining an additional buffer descriptor pointing to the desired destination location to the front of the packet before calling NdisTransferData().

Fixed: Connection Error 'Opening port Error 797: The connection failed because the modem (or other connecting device) was not found.' after waking the machine from Standby. There were no OID_PNP_XXX handlers in the protocol. Additionally, it turned out that TAPI requests OID_TAPI_PROVIDER_INITIALIZE after returning from Standby, although it never shuts the provider down with OID_TAPI_PROVIDER_SHUTDOWN. The protocol did not allow re-initialization without shutdown. Fixed this by adding the missing OID_PNP_XXX handlers and allowing TAPI provider re-initialization without a prior shutdown.

n      Version 0.90, January 30th, 2000

First release that actually works! A wholehearted Thank You! to Jerome Whelan who invested so much time to provide me with the comprehensive feedback that I needed to make this protocol functional.

Fixed: Installation Error 'Could not add the requested component. The error is: Invalid access to memory location.' on some machines. On those, the loader crashed when loading RASPPPOE.DLL, because I had linked it with the /align:16 linker switch. Removed the switch from the build settings.

Fixed: Connection Error 'Disconnected. Error 619: The specified port is not connected.' on all connection attempts. NDISWAN failed to recognize the PPP frames within the complete received Ethernet frames the protocol passed to it, although I had specified the HeaderPadding correctly as outlined in the DDK documentation. Fixed this by setting the HeaderPadding to zero and only passing the portion of the buffer with the actual PPP frame to NDISWAN.

Fixed: Ping Timeouts with certain packet sizes. NDISWAN passes up to four bytes more to a WAN miniport's send handler than the WAN miniport indicated as its MaxFrameSize. Apparently a WAN miniport driver writer is expected to make assumptions about the PPP HDLC overhead NDISWAN adds before passing a packet to the miniport - four bytes of simple PPP HDLC framing (Address and Control fields and Protocol Identifier). Fixed this by adjusting the maximum frame and total sizes accordingly and changing the size limit comparisons.

n      Version 0.80, January 15th, 2000

Initial public release

9. Contacting the author

Before contacting me, please bear in mind that you are getting this piece of software for free. You cannot expect me to spend my time providing 'tech support'. If you have a problem that you cannot resolve after reading above documentation thoroughly, please do the following:

Check if there is updated information or a newer version of this protocol available on the RASPPPOE Home Page.

Check the System Event Log for any events logged by the protocol:

Click the Start button, then select Programs, then Administrative Tools (Common), then Event Viewer.

In the upcoming Event Viewer window, open the Log menu and select System.

Look through the list in the window for any entries from source RMSPPPOE.

Double-click each entry you find to bring up the Event Detail window.

If the event Description still does not help you find the culprit, please include all log entry data in your e-mail:

Right-click in the field under Description:, select Select All, right-click again and select Copy, then paste the text into your e-mail to me.

Right-click in the field under Data:, select Select All, right-click again and select Copy, then paste the text into your e-mail to me.

Of course, developer suggestions for fixing the known issues, success stories (please mention your service provider, so that I know which ones this protocol works with) or just 'thank you' notes are always welcome.

You can contact me via the e-mail address: Robert.Schlabbach@gmx.net.