readme98.htm

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    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>Note that the <strong>Dial-Up Adapter's IPMTU</strong>
    registry parameter is also set to the override value, since
    the <strong>Dial-Up Adapter</strong> ignores the <strong>MaxFrameSize</strong>
    returned by the driver. This means that this setting will
    affect the MTU of <strong>all</strong> dial-up connections,
    and that the use of any other MTU adjustment tool will
    possibly conflict with this option, altering it.</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.</p>
</blockquote>

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

<blockquote>
    <h4><a name="Advanced5"><u>5.5</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
    automatically when you log on to <strong>Windows</strong> and
    kept until you log off. 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
            To</strong> window and <strong>connecting at least
            once</strong>.</li>
        <li>Double-click the <strong>My Computer</strong> icon on
            your desktop. If you are running <strong>Windows ME</strong>,
            double-click the <strong>Control Panel</strong> icon
            in the opened window.</li>
        <li>Double-click the <strong>Dial-Up Networking</strong>
            icon in the last opened window.</li>
        <li>If you are running <strong>Windows 98/98SE</strong>,
            click on the <strong>Connections</strong> menu of the
            <strong>Dial-Up Networking</strong> window and select
            <strong>Settings...</strong> to bring up the <strong>Dial-Up
            Networking</strong> settings dialog. In this dialog, <strong>clear</strong>
            the <strong>Prompt for information before dialing</strong>
            checkbox.</li>
        <li>If you are running <strong>Windows ME</strong>,
            locate the dial-up connection you want to make <strong>&quot;always
            on&quot;</strong>, right-click it and select <strong>Properties</strong>.
            In the properties dialog, select the <strong>Security</strong>
            tab and <strong>check</strong> the <strong>Connect
            automatically</strong> checkbox. Then select the <strong>Dialing</strong>
            tab, check the <strong>This is the default Internet
            connection</strong> checkbox, select <strong>Always
            dial my default connection</strong> and <strong>clear</strong>
            the <strong>Enable idle disconnect</strong> and the <strong>Disconnect
            when connection may not be needed</strong> checkboxes.</li>
        <li>Click <strong>OK</strong> to save the changes.</li>
        <li>Now <strong>click</strong> and <strong>drag</strong>
            the <strong>desktop icon</strong> of the dial-up
            connection and drop it under <strong>Start Menu</strong>,
            <strong>Programs</strong>, <strong>into</strong> the <strong>Startup</strong>
            folder.</li>
        <li><strong>Log off</strong> and <strong>log on</strong>
            again. <strong>Windows</strong> will establish the
            connection automatically and keep it connected until
            you log off.</li>
    </ul>
</blockquote>

<blockquote>
    <h4><a name="Advanced6"><u>5.6</u></a><u> Addressing a
    specific Service and/or Access Concentrator</u></h4>
    <p>In most cases, there is <strong>no</strong> need to
    address a specific Service or Access Concentrator. But should
    you have a need to do so, you can use the <strong>phone
    number</strong> field of your dial-up connection to specify a
    <strong>Service</strong>, <strong>Access Concentrator</strong>
    or <strong>both</strong>. The following phone number formats
    are possible:</p>
    <ol type="A" start="1">
        <li><strong>&quot;0&quot;</strong>: The protocol will
            connect to the <strong>default</strong> Service of
            the <strong>first</strong> Access Concentrator that <strong>replies</strong>
            to the connection request.</li>
        <li><strong>&quot;Service-Name&quot;</strong>: The
            protocol will connect to the <strong>first</strong>
            Access Concentrator that <strong>replies</strong>
            offering the <strong>requested</strong> Service.</li>
        <li><strong>&quot;Access-Concentrator\&quot;</strong>:
            The protocol will connect to the <strong>default</strong>
            Service of the <strong>named</strong> Access
            Concentrator.</li>
        <li><strong>&quot;Access-Concentrator\Service-Name&quot;</strong>:
            The protocol will connect to the <strong>requested</strong>
            Service of the <strong>named</strong> Access
            Concentrator.</li>
    </ol>
    <p>The <strong>RASPPPOE</strong> application uses format <strong>A</strong>
    for the phone number if you create a connection for an <strong>adapter</strong>
    and format <strong>C</strong> or <strong>D</strong> if you
    create a connection for a specific <strong>service</strong>.</p>
    <h4><a name="Advanced7"><u>5.7</u></a><u> Enabling the
    protocol to act as a PPPoE Access Concentrator</u></h4>
    <p>The protocol is able to act as a PPPoE <strong>Access
    Concentrator</strong> (server). This feature can be used for
    testing purposes, but also offers a <strong>future</strong>
    potential for advanced provider services like <strong>instant
    messaging</strong> or <strong>instant e-mail</strong> even
    for users who are <strong>offline</strong> at the time a
    message is received. The server capability is fully
    integrated with the operating system's <strong>Dial-Up Server</strong>
    component. No PPPoE-specific configuration is needed. The
    protocol uses the current <strong>Computer Name</strong> as
    the <strong>Access Concentrator Name</strong> and offers <strong>any
    Service Name</strong> requested by a client. Note that the
    protocol will <strong>not</strong> offer any services until
    you <strong>explicitly</strong> enable its dial-up devices to
    accept incoming connections. To do this, follow these steps:</p>
    <ul>
        <li>Double-click the <strong>My Computer</strong> icon on
            your desktop. If you are running <strong>Windows ME</strong>,
            double-click the <strong>Control Panel</strong> icon
            in the opened window.</li>
        <li>Double-click the <strong>Dial-Up Networking</strong>
            icon in the last opened window.</li>
        <li>In the <strong>Dial-Up Networking</strong> window,
            click on the <strong>Connections</strong> menu of the
            <strong>Dial-Up Networking</strong> window and select
            <strong>Dial-Up Server...</strong> to bring up the <strong>Dial-Up
            Server</strong> settings dialog. If you cannot find
            this menu item, you first need to install the <strong>Dial-Up
            Server</strong> component. Go to <strong>Control
            Panel</strong>, <strong>Add/Remove Programs</strong>,
            <strong>Windows Setup</strong>, <strong>Communications</strong>
            and enable the component there.</li>
        <li>If you see a message saying <strong>&quot;No modem is
            installed.&quot;</strong>, or you don't see any tab
            with the name of your <strong>network adapter</strong>
            on it, you may have to reboot to make <strong>Dial-Up
            Server</strong> recognize the dial-up devices exposed
            by the protocol (see <a href="#KnownIssue2">Known
            Issues</a>).</li>
        <li>Select the tab with the name of the <strong>network
            adapter</strong> through which you want to accept
            incoming <strong>PPP over Ethernet</strong>
            connections and select <strong>Allow caller access</strong>
            on that page. Click the <strong>Change Password...</strong>
            and the <strong>Server Type...</strong> buttons to
            configure the access.</li>
        <li>Click <strong>OK</strong> to save the changes and
            enable the server.</li>
        <li>If you want to disable the server, open the <strong>Dial-Up
            Server</strong> settings dialog again, select the tab
            with the name of the <strong>network adapter</strong>
            on it and select <strong>No caller access</strong>.
            Then click <strong>OK</strong> to stop the protocol
            from offering services on that network adapter.</li>
    </ul>
    <p>For further help on using <strong>Dial-Up Server</strong>,
    please refer to the operating system's documentation on this
    topic.</p>
    <p><strong>NOTE:</strong> Machines running <strong>Windows 98/98SE/ME</strong>
    will <strong>not</strong> be able to successfully connect to
    another <strong>Windows 98/98SE/ME</strong> machine acting as
    a PPPoE <strong>Access Concentrator</strong> (server) due to <a
    href="#KnownIssue3">this</a> known issue.</p>
</blockquote>

<hr>

<h3><a name="Section6"><u>6.</u></a><u> Troubleshooting</u></h3>