readme98.htm

学习书籍

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

<blockquote>
    <h4><a name="Trouble1"><u>6.1</u></a><u> RASPPPOE application
    does not list the desired adapter</u></h4>
    <p>First, be aware that you can use this protocol only on <strong>Ethernet</strong>
    adapters. As <strong>PPP over Ethernet</strong> only works
    over Ethernet, the protocol will only bind itself to Ethernet
    adapters (<strong>NdisMedium802_3</strong>). Adapters that do
    not support this medium type (e.g. internal or USB broadband
    modems that do <strong>not</strong> expose a standard
    Ethernet interface <strong>through their driver</strong>) are
    <strong>not</strong> supported by this protocol.</p>
    <p>Check in <strong>Device Manager</strong> whether the
    network adapter connected to your broadband modem is enabled
    and working properly. If it is, try <strong>rebooting</strong>
    the machine. If that does not help, try <strong>uninstalling</strong>
    the protocol, <strong>rebooting</strong>, <strong>re-installing</strong>
    and <strong>rebooting</strong> again. Your adapter should be
    listed now.</p>
    <h4><a name="Trouble2"><u>6.2</u></a><u> RASPPPOE application
    reports &quot;RASPPPOE - No Service Offers Received&quot;
    when querying available services</u></h4>
    <p>This error message means that the protocol did not receive
    <strong>any</strong> response from your service provider. You
    should check the following things in order:</p>
    <ol>
        <li>Check if your broadband modem has successfully
            established a link with its counterpart. Most DSL
            modems have a <strong>Sync</strong> 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.</li>
        <li>Check in <strong>Device Manager</strong> if the <strong>network
            adapter</strong> your broadband modem is connected to
            is enabled and working properly.</li>
        <li>Bring up the <strong>Network Configuration</strong>
            window, select the network adapter your broadband
            modem is connected to and click <strong>Properties</strong>.
            In the <strong>Properties</strong> window, select the
            <strong>Advanced</strong> tab, look through the
            options and make sure that the correct <strong>Line
            Speed</strong> and <strong>duplex mode</strong> is
            selected (most DSL modems only support <strong>10Mbps
            half duplex</strong> mode). If your network adapter
            has several connectors at the back, make sure the
            correct connector is selected, which is most likely <strong>Twisted
            Pair (TP)</strong>.</li>
        <li>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 <strong>&quot;crossed&quot;</strong>
            connector on them, so you will need a <strong>straight</strong>
            cable to connect it <strong>directly</strong> to a
            network adapter, while you need to use a <strong>crossed</strong>
            cable <strong>or</strong> use an <strong>uplink</strong>
            port to connect it to a <strong>hub</strong> or <strong>switch</strong>.</li>
        <li>Check with your service provider whether they
            currently have a service outage.</li>
    </ol>
    <h4><a name="Trouble3"><u>6.3</u></a><u> Connection attempt
    fails with &quot;Error 678: There was no answer.&quot;</u></h4>
</blockquote>

<blockquote>
    <p>First, you should check whether you can get <strong>any</strong>
    reply from your service provider with the <strong>Dial-up
    Connection Setup </strong>application provided with the
    protocol:</p>
    <ul>
        <li>Click the <strong>Start</strong> button on the
            taskbar and select <strong>Run...</strong> to bring
            up the <strong>Run</strong> dialog box.</li>
    </ul>
    <ul>
        <li>Type <strong>RASPPPOE</strong> in the edit field and
            click the <strong>OK</strong> button to run the <strong>Dial-up
            Connection Setup</strong> application.</li>
    </ul>
    <ul>
        <li>If the application quits with an error message,
            follow the advice it gives.</li>
    </ul>
    <ul>
        <li>A dialog box comes up with a combo box labeled <strong>Query
            available PPP over Ethernet Services through Adapter:</strong>
            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.</li>
    </ul>
    <ul>
        <li>Click the <strong>Query Available Services</strong>
            button. If an error message is displayed, continue <a
            href="#Trouble2">here</a> for further help.</li>
    </ul>
    <ul>
        <li>If the list view shows one or more offered services
            and you had tried to connect to a <strong>specific</strong>
            <strong>Service</strong> and/or <strong>Access
            Concentrator</strong>, make sure the one you had
            tried to connect to is listed. If you find your
            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 <strong>Phone
            number</strong> field in your existing dial-up
            connection accordingly.</li>
    </ul>
    <ul>
        <li>Click the <strong>Exit</strong> button to quit the
            application.</li>
    </ul>
</blockquote>

<blockquote>
    <p>If you do <strong>not</strong> want to connect to a
    specific <strong>Service</strong> and/or <strong>Access
    Concentrator</strong>, make sure the <strong>Phone number</strong>
    field of your dial-up connection really only contains <strong>a
    single zero digit</strong>.</p>
    <h4><a name="Trouble4"><u>6.4</u></a><u> Connection is
    successfully established, but some (or all) Internet websites
    do not load properly</u></h4>
    <p>This is usually a sign of an <strong>MTU problem</strong>.
    A possible cause for this could be that the <strong>Dial-Up
    Adapter's</strong> <strong>common</strong> <strong>IP MTU</strong>
    setting was altered to a value too high for <strong>PPP over
    Ethernet</strong>. This setting is altered e.g. when you
    change the <strong>IP Packet Size</strong> value on the <strong>Advanced</strong>
    tab of the <strong>Dial-Up Adapter Properties</strong> to
    something other than the <strong>&quot;PPP over Ethernet&quot;</strong>
    setting added by the protocol, or by some MTU tools. You
    should not change this setting, nor use any tools that alter
    it when using <strong>PPP over Ethernet</strong>. To ensure
    this setting is correct do the following:</p>
    <ul>
        <li>Right-click the <strong>Network Neighborhood</strong>
            icon on your desktop and select <strong>Properties</strong>
            to bring up the <strong>Network Configuration</strong>
            window.</li>
        <li>Locate <strong>any</strong> <strong>PPP over Ethernet
            Protocol -&gt; </strong><em><strong>Adapter Name</strong></em>
            entry, select it and click the <strong>Properties</strong>
            button.</li>
        <li>Close the properties window with the <strong>Cancel</strong>
            button.</li>
        <li>Close the <strong>Network Configuration</strong>
            window with the <strong>OK</strong> button. If <strong>Windows
            </strong>prompts you to <strong>reboot</strong>, the <strong>IP
            MTU</strong> setting had to be corrected. Allow the
            reboot and try if the connection works properly.</li>
    </ul>
    <p>If that did not help, you should determine the <strong>Path
    MTU</strong> to the problem site(s) (<strong>Note:</strong>
    The method described here does not work with all servers. If
    you get no reply at all from a server or a number below <strong>548</strong>,
    you cannot determine the Path MTU to the server in question):</p>
    <p>Connect, open an <strong>MS-DOS Prompt</strong> and run:</p>
    <blockquote>
        <p><strong>ping -f -l xxxx </strong><em><strong>Address</strong></em></p>
    </blockquote>
    <p>Where <em>Address</em> is the <strong>name</strong> or <strong>IP
    address</strong> of the server you have problems accessing.
    For <strong>xxxx</strong>, start with <strong>1464</strong>
    and <strong>lower</strong> the number until you get a reply.
    Then add <strong>28</strong> to the highest number at which
    you get a reply. The result is the <strong>Path MTU</strong>.</p>
    <p><strong>Example:</strong> You start getting replies at <strong>ping
    -f -l 1372 </strong><em><strong>Address</strong></em>. The
    Path MTU is 1372 + 28 = <strong>1400</strong> bytes in this
    case.</p>
    <p>Normally, the Path MTU to all servers should be <strong>1492</strong>.
    However, some service providers appear to have a
    configuration problem which reduces the Path MTU. If you
    determine a Path MTU lower than <strong>1492</strong> to
    several (or all) servers on the Internet, you should enable
    the <a href="#Advanced2">MTU override</a> option and set it
    to the <strong>Path MTU</strong> 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.</p>
    <h4><a name="Trouble5"><u>6.5</u></a><u> Connection is
    successfully established, but there are periodic pauses while
    using the Internet</u></h4>
    <p>This is typically the result of leaving the <strong>TCP/IP-&gt;</strong><em><strong>Adapter
    Name</strong></em> entry in the network configuration, <strong>not</strong>
    assigning any <strong>fixed</strong> IP address to it, and
    not having any <strong>DHCP server</strong> on the local
    network either. This also makes the machine take
    significantly longer to boot up. To fix this, right-click the
    <strong>Network Neighborhood</strong> (Windows 98/98SE) or <strong>My
    Network Places</strong> (Windows ME) icon on your desktop and
    select <strong>Properties</strong> to bring up the <strong>Network
    Configuration</strong> window. In this window, locate and
    select the <strong>TCP/IP-&gt;</strong><em><strong>Adapter
    Name</strong></em> entry for the network adapter connected to
    your broadband modem. If this network adapter is<strong>
    dedicated</strong> to your broadband modem, simply click the <strong>Remove</strong>
    button. If you also want to access other local machines
    through the same network adapter, click the <strong>Configure</strong>
    button and assign a <strong>fixed IP address</strong> (e.g. <strong>192.168.0.1</strong>
    with subnet mask <strong>255.255.255.0</strong>).</p>
    <h4><a name="Trouble6"><u>6.6</u></a><u> Cannot get Internet
    Connection Sharing to share the PPPoE connection</u></h4>
    <p>A common cause of this is that <strong>Internet Connection
    Sharing</strong> was <strong>incorrectly</strong> set up to
    use a <strong>network adapter</strong> for Internet access,
    which <strong>bypasses</strong> the <strong>PPP over Ethernet
    Protocol</strong>. Re-configure <strong>Internet Connection
    Sharing</strong> and make sure you select the <strong>Dial-Up
    Adapter</strong> as the device through which to access the
    Internet. For further help, see this article in the <strong>Microsoft</strong>
    support database:</p>
    <p align="center"><a
    href="http://support.microsoft.com/support/kb/articles/Q273/5/87.ASP">Q273587
    - How to Configure ICS for Use with DSL Connections That Use
    PPPoE Adapters</a></p>
</blockquote>

<blockquote>
    <h4><a name="Trouble7"><u>6.7</u></a><u> The &quot;Override
    Maximum Transfer Unit&quot; option does not remain checked</u></h4>
</blockquote>

<blockquote>
    <p>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>
</blockquote>

<hr>

<h3><a name="Section7"><u>7.</u></a><u> Known Issues</u></h3>

<p>This section documents known issues with the protocol.</p>

<blockquote>
    <h4><a name="KnownIssue1"><u>7.1</u></a><u> If the installer
    requires a reboot to finish, the initial connection will not
    have an icon in the system tray</u></h4>
    <p>If the installer detects that it can not start the
    protocol dynamically, it informs the user that a reboot is
    required. Upon the next reboot, the installer creates a dial-up
    connection and brings up the <strong>Connect To</strong>
    dialog <strong>before</strong> the task bar appears. If the
    connection is established, it will be fully functional, but