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to display</a> may be of interest. Users having problems with VPN
software might try if <a href="#Advanced2">overriding the MTU
reported by the protocol</a> helps. Users with flat rate Internet
access may be interested in <a href="#Advanced6">making the
connection &quot;always on&quot;</a>. If you are interested in
using the protocol's server capability, please see <a
href="#Advanced8">Enabling the protocol to act as a PPPoE Access
Concentrator</a>.</p>

<p>To bring up the protocol settings for an adapter:</p>

<ul>
    <li>If you are running <strong>Windows 2000</strong>, right-click
        the <strong>My Network Places</strong> icon on your
        desktop and select <strong>Properties</strong> to bring
        up the <strong>Network and Dial-up Connections</strong>
        window.</li>
    <li>If you are running <strong>Windows XP/2002</strong>,
        click the <strong>Start</strong> button, select <strong>Control
        Panel</strong>, then click <strong>Network and Internet
        Connections</strong> and then click the <strong>Network
        Connections</strong> control panel icon to bring up the <strong>Network
        Connections</strong> window.</li>
    <li>Locate the <strong>Local Area Connection</strong> (Note
        well: <strong>not</strong> your dial-up connection entry!)
        of the adapter the protocol settings of which you wish to
        modify, right-click it and select <strong>Properties</strong>.</li>
    <li>In the list of components used by this connection, select
        <strong>PPP over Ethernet Protocol</strong> (<strong>BEWARE:</strong>
        You must <strong>not</strong> click on the checkbox, as
        this will disable the protocol for this adapter! Make
        sure you click on the protocol <strong>name</strong>)
        then click the <strong>Properties</strong> button to
        bring up the protocol's settings for this adapter.</li>
    <li>Changes to the protocol settings take effect when you
        close the <strong>PPP over Ethernet Protocol Properties</strong>
        window with the <strong>OK</strong> button unless noted
        otherwise.</li>
</ul>

<p>The <strong>General</strong> tab offers the following settings:</p>

<blockquote>
    <h4><a name="Advanced1"><u>5.1</u></a><u> Limit TCP MSS
    Maximum Segment Size (MSS) Option</u></h4>
    <p>When using <strong>Internet Connection Sharing</strong>,
    the client machines are completely unaware of the packet size
    restrictions imposed by the nature of <strong>PPP over
    Ethernet</strong> (in contrast to e.g. <strong>modem</strong>
    or <strong>ISDN</strong> connections, which allow passing
    arbitrarily sized packets). Typically, a client assumes that
    packets of up to <strong>1500</strong> bytes can be passed
    and thus indicates a <strong>Maximum Segment Size</strong> of
    <strong>1460</strong> bytes (1500 bytes minus 40 bytes for
    the TCP and IP headers) when opening a <strong>TCP</strong>
    session, resulting in either side of the connection sending
    packets up to <strong>1500</strong> bytes in size, too large
    to pass through a PPP over Ethernet connection, which can
    only pass packets up to <strong>1492</strong> bytes in size.
    These oversized packets are then often <strong>silently</strong>
    dropped at either side of the <strong>PPP over Ethernet</strong>
    connection, leading to <strong>delays</strong> or <strong>hangs</strong>
    when accessing the Internet from a client.</p>
    <p>To work around this problem, this option makes the
    protocol scan all network packets it sends and receives for
    the <strong>TCP Maximum Segment Size (MSS)</strong> option
    and, if a value greater than either the default (<strong>1492</strong>)
    or the <strong>overridden</strong> MTU <strong>minus 40</strong>
    for the IP and TCP headers (i.e. <strong>1452</strong> in
    case of the default MTU) is found, <strong>change</strong> it
    to this value, recalculate the TCP checksum and pass the
    modified packet. This option is <strong>enabled</strong> by
    default. If you are <strong>not</strong> using <strong>Internet
    Connection Sharing</strong>, you can <strong>disable</strong>
    this option to save a little (very little) CPU power,
    although leaving it enabled has <strong>no</strong> negative
    side effects.</p>
    <h4><a name="Advanced2"><u>5.2</u></a><u> Override Maximum
    Transfer Unit</u></h4>
    <p>By default, the protocol will report an MTU of <strong>1492</strong>
    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 <strong>lower</strong> MTU was found to help with
    certain VPN software packages which &quot;blindly&quot; 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 <strong>Override
    Maximum Transfer Unit</strong> checkbox and type the MTU the
    protocol should report in the <strong>Maximum Transfer Unit (MTU)</strong>
    edit box. The valid range is <strong>576</strong> through <strong>1492</strong>
    bytes. Reducing the MTU by 32 bytes to <strong>1460</strong>
    should generally suffice to make misbehaved VPN software work.<strong>
    Note:</strong> Regardless of this setting, the protocol will
    always send and receive packets of up to <strong>1492</strong>
    bytes. Only the MTU initially <em>reported</em> by the
    protocol (the <strong>MaxFrameSize</strong> value in response
    to the <strong>OID_WAN_GET_INFO</strong> request) and, if
    enabled, <a href="#Advanced1">the TCP MSS option limit</a>
    are affected by this setting.</p>
    <p>For any changes to this setting to take effect, you need
    to <strong>disable</strong> and <strong>re-enable</strong>
    the <strong>Local Area Connection</strong> for the
    corresponding network adapter once, or <strong>reboot</strong>.</p>
    <p><strong>NOTE:</strong> This option will only &quot;stick&quot;
    if you enter an MTU <strong>other than 1492</strong>. If you
    only check the checkbox, but leave the MTU at <strong>1492</strong>,
    the protocol will recognize the default value and <strong>clear</strong>
    the checkbox the next time you open the properties dialog,
    because the MTU was not actually overridden.</p>
    <h4><a name="Advanced3"><u>5.3</u></a><u> Number of lines (WAN
    endpoints)</u></h4>
    <p>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 a <strong>reboot</strong> to take
    effect.</p>
</blockquote>

<p>The <strong>Advanced</strong> tab offers the following
settings:</p>

<blockquote>
    <h4><a name="Advanced4"><u>5.4</u></a><u> Specify Link Speed</u></h4>
    <p>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
    <strong>Specify Link Speed</strong> checkbox and type the
    link speed the protocol should report in the <strong>Link
    Speed (kbps)</strong> edit box, in kilobits per second. If
    you want to revert to displaying the adapter's link speed,
    clear the <strong>Specify Link Speed</strong> checkbox.<strong>
    Note:</strong> This setting has absolutely <strong>no</strong>
    effect on the network traffic through this adapter; it is
    purely a <strong>cosmetic</strong> setting. This setting
    takes effect the next time you establish a <strong>PPP over
    Ethernet</strong> connection.</p>
    <h4><a name="Advanced5"><u>5.5</u></a><u> Event Logging
    options</u></h4>
    <p>The protocol can inform you about informational events,
    warnings and errors during operation by logging events to the
    <strong>System event log</strong>. By default, the protocol
    logs <strong>all</strong> 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 <strong>any</strong>
    events.</p>
    <ul>
        <li><strong>Log Informational Events</strong> will log
            any vendor-specific information received.</li>
        <li><strong>Log Warnings</strong> will log non-fatal
            warnings that do not necessarily prevent successful
            operation.</li>
        <li><strong>Log Errors</strong> will log fatal errors
            that prevent correct function of the protocol.</li>
    </ul>
    <p>You use <strong>Event Viewer</strong> to view any events
    logged by this protocol:</p>
    <ul>
        <li>Right-click the <strong>My Computer</strong> icon on
            your desktop and select <strong>Manage</strong> to
            bring up the <strong>Computer Management</strong>
            window.</li>
        <li>In the tree on the left-hand side, expand the <strong>Event
            Viewer</strong> branch, select the <strong>System</strong>
            sub branch and press <strong>F5</strong> to refresh
            the view on the right-hand side. Look for log entries
            from source <strong>RMSPPPOE</strong> there.</li>
        <li>To get a detailed description of a logged event,
            double click the event in the view on the right-hand
            side.</li>
    </ul>
</blockquote>

<p>Beyond these settings, the protocol offers the following
possibilities:</p>

<blockquote>
    <h4><a name="Advanced6"><u>5.6</u></a><u> Making a dial-up
    connection &quot;always on&quot;</u></h4>
</blockquote>

<blockquote>
    <p>Users who enjoy flat rate Internet access may find it
    desirable to turn their connection into an <strong>&quot;always
    on&quot;</strong> 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 <strong>&quot;always
    on&quot;</strong>, follow these steps:</p>
    <ul>
        <li>If your service provider requires authentication,
            make sure you have saved the password by checking the
            <strong>Save Password</strong> checkbox in the <strong>Connect
            </strong><em><strong>Connection Name</strong></em>
            window and <strong>connecting at least once</strong>.</li>
        <li>Right-click the <strong>My Network Places</strong>
            icon on your desktop and select <strong>Properties</strong>
            to bring up the <strong>Network and Dial-up
            Connections</strong> window.</li>
        <li>Locate the <strong>Dial-up</strong> connection you
            created for <strong>PPP over Ethernet</strong>, right-click
            it and select <strong>Properties</strong>.</li>
        <li>Select the <strong>Options</strong> tab and clear <strong>all</strong>
            checkboxes under <strong>Dialing options</strong>.</li>
        <li>Under <strong>Redialing options</strong>, set <strong>Idle
            time before hanging up:</strong> to <strong>never</strong>
            and check the <strong>Redial if line is dropped</strong>
            checkbox.</li>
        <li>Click <strong>OK</strong> to save the changes.</li>
        <li>Now click the <strong>Start</strong> button, select <strong>Settings</strong>
            then <strong>Control Panel</strong> to open the <strong>Control
            Panel</strong> window.</li>
        <li>In the <strong>Control Panel</strong> window, double-click
            <strong>Scheduled Tasks</strong>.</li>
        <li>In the <strong>Scheduled Tasks</strong> window,
            double-click <strong>Add Scheduled Task</strong>.</li>
        <li>On the welcome screen of the <strong>Scheduled Task
            Wizard</strong>, click <strong>Next</strong>.</li>
        <li>At the program selection step, click <strong>Browse...</strong>
            and browse to your <strong>WINNT\System32</strong>
            directory.</li>
        <li>Type <strong>RAS</strong><font color="#FF0000"><strong>PHONE</strong></font><strong>.EXE</strong>
            (note the spelling!) in the <strong>File name:</strong>
            edit box or locate it in the directory and select it
            and click <strong>Open</strong>.</li>
        <li>Make up a name for this task and under <strong>Perform
            this task:</strong> select <strong>When my computer
            starts</strong>. Click <strong>Next</strong>.</li>
        <li>Enter your password. <strong>Note:</strong> The task <strong>must</strong>
            be run under the same account which the dial-up entry
            was created under.</li>
        <li>At the final step, make sure that <strong>Open
            advanced properties for this task when I click finish</strong>
            is checked and click <strong>Finish</strong>.</li>
        <li>In the advanced properties, edit the <strong>Run:</strong>
            edit box and append the command-line parameters
            &quot;<strong> -d &quot;</strong><em><strong>Connection
            Name</strong></em><strong>&quot;</strong>&quot;.</li>
        <li>Go to the <strong>Settings</strong> tab and clear <strong>all</strong>
            checkboxes on that page.</li>
        <li>Click <strong>OK</strong> to close the task's
            properties.</li>
        <li>Finally, you need to make a little registry change to
            prevent <strong>Windows</strong> from disconnecting
            when a user logs on and off again:</li>
    </ul>
</blockquote>