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><A
NAME="HOW-DOES-IT-WORK"
>2. How Does an Emulator Work?</A
></H1
><P
> It is important to understand how a SLIP/PPP emulator works in
general, to be aware of its limitations. First, you do not need to install
the emulator on your machine. It runs on your remote host only. What you
need on your machine is the TCP/IP and SLIP or PPP protocols installed in
your kernel (more on that in a bit), and some clients.
</P
><P
> Here's what happens: you send network requests from your machine
to your remote host over the SLIP/PPP link. The emulator grabs them and
sends them out to the Net at large. Then, incoming data is sent back from
the Net to your account on the remote host, where the emulator grabs it
and sends it back over the SLIP/PPP link to your machine. So, to the Net
it appears as if you are working out of your account on the remote host,
but to you it looks like you are really connected right to the Net.
</P
><P
> As you can see, this can confuse stuff that is incoming from the
Net. For example, talk doesn't work via an emulator, because the incoming
talk request tries to start the remote hosts talk daemon, not yours.
</P
><P
> The other big difference between an emulator and real SLIP/PPP is
you are NOT assigned your own IP address; remember, you are only
converting a dialup account to a SLIP/PPP connection.
</P
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><H2
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><A
NAME="WHAT-IS-TIA"
>2.1. What is TIA?</A
></H2
><P
> <A
HREF="http://www.marketplace.com/tia/tiahome.html"
TARGET="_top"
>The Intenet Adaptor</A
>
was written by the fine folks at marketplace.com. They have
quit working on it now, and consider it a 'mature' product. The last
version is 2.05; if you are going to use TIA, please get this version.
<DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P
><B
>Note: </B
> At last report, marketplace.com have gone out of business.
</P
></BLOCKQUOTE
></DIV
>
</P
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><H2
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><A
NAME="WHAT-IS-SLIRP"
>2.2. What is SLiRP?</A
></H2
><P
> This is a freeware application, covered under the GNU Public
License. It is out of beta, and is real stable. It sports a few more
features than TIA, and is (reportedly) easier on host resources.
Available at fine Linux FTP sites everywhere.
</P
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><A
NAME="WHAT-ABOUT-TERM"
>2.3. What about Term?</A
></H2
><P
> If you don't have root access to your machine for one reason or
another, and you can't persuade someone who does to install SLIP and dip,
then you won't have much choice except to use Term. If you want to know
more about Term, please read the HOWTO on Sunsite.
</P
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><A
NAME="WHAT-ABOUT-REAL-SLIP"
>2.4. What about real SLIP/PPP?</A
></H2
><P
> Hey, a lot of places are offering real SLIP/PPP at reasonable
prices for non-dedicated dialup nowadays. If you can afford it, or feel
the need, go for it. The Real Thing is always better than emulation.
However, one of the things an emulator provides is security; it acts as
an impregnable firewall, and with it you are pretty much as bulletproof
as your provider is. You'll pay for it though, emulation is slower, and
does not fully support every protocol. Still and all, emulation is good
enough for most people, and is a fine way to connect to the Net.
</P
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