Let me begin by telling you what my objective is, and perhaps a few
solutions will come to mind:
I am running a version of X-Windows on a Pentium PC with the
Slackware distribution of Linux. This PC has an internal 28800
I have a DEC 5000/240 workstation running Ultrix (very much like
Berkeley UNIX), and it has a 28800 baud modem connected to it.
This workstation is also connected to the INTERNET.
I want to be able to dial up the workstation from the PC, and
do the following:
 Run Mosaic (or Netscape) on the PC and browse the
INTERNET just as I can when I am using the
 Open "xterm" windows on the PC, and have each window
actually be running shells on the workstation,
and thus give me a kind of remote console to
 Do FTP and have files appear on the PC's local disk.
I have read numerous articles posted to this newsgroup, and I have a vague
understanding of what is required. But I would like a comprehensive
introduction, in the form of a step-by-step guide, to the mechanisms required
to achieve the goals I have listed. I don't want to buy a book on the
subject, partly because books are inevitably a little behind the times in
this area. I think the solution to my problem will be of wide interest,
and may merit a kind of FAQ posting in this group.
Just to get the ball rolling, let me give you a snapshot of my current
[a] Ethernet is nothing more than a high-speed serial line on
which specially structured data packets (group of bytes)
are transmitted and received.
[b] By using special hardware (an Ethernet board) and software
(various drivers, etc), Linux can have an Ethernet connection
to other PC's running Linux, and also the INTERNET.
[c] A modem or direct RS-232 connection to a PC's serial port
is another way the PC can send and recieve serial data.
[d] In principle it is possible to use the PC's serial port
in place of the Ethernet card as a way of transmitting
and receiving serial data between machines in a
"client"-"server" relationship. So, anything that can
be done with an Ethernet connection under Linux, could,
in principle, be done with a modem or direct RS-232 connection,
provided that the PC running Linux connects to a system
that can act as a "server" to feed the PC the right kind
[e] Just as there is an Ethernet "protocol" defining the byte
structure of the serial data packets sent on Ethernet cables,
there are recently defined protocols for modem and RS-232 lines:
PPP ("Point-To-Point Protocol"),
SLIP ("Serial Line Interface Protocol"),
CSLIP ("?????? Serial Line Interface Protocol").
Now my understanding of the situation grows even weaker, and so the following
is even more speculative [which is precisely what I want filled in and
corrected]. I know I am wrong when I write the following, but I am writing
it to draw feedback:
[f] When connecting two or more computers using a PPP or SLIP
method over a modem (or direct RS-232) it is necessary to
have special software running on each of the computers
One part of the software required are executable programs:
 a PPP or SLIP "server" daemon (like "pppd" or "slipd")
that is constantly running in the background after
bootup -- always ready to handle future PPP or SLIP
 a PPP or SLIP "client" program that is called by the
system after connecting to a machine running the
"server" program. One of these "client" programs is
called "slattach" ("SLIP attach").
The other part of the software required for SLIP and PPP
operation is a modification to the __operating_system__
itself!! This means that part of the "kernel" (the source
code for the actual operating system, often written in C code)
must be modified, and the system program must be re-compiled,
and the system rebooted. The kernel modification usually
takes the form of a few pages of C code, and this code is
often included among the various optional files distributed
with your system's original source code (for example, the
"Slackware" distribution of Linux). Also, you may need to
put some "include" and "library" files on the harddrive
to before re-compiling the system (because such files define
macro's, constants, and functions or function prototypes
necessary for compiling the new PPP or SLIP system kernel
There is a way to check if your operating system has SLIP
or PPP capability in its kernel through "ifconfig" (a program).
[g] A typical SLIP session might transpire as follows:
 There is a workstation or PC that is equiped
with a system that has the SLIP or PPP kernel
functions, and is running the corresponding
daemon ("slipd" or "pppd") in the background.
This workstation or PC also has a modem or
direct RS-232 line.
 A person approaches a PC running Linux and some
form of X-Windows (the X-Windows part is not
really necessary, but I want to assume in the
following that it is running). This person
has a modem (or RS-232 line), and somehow gains
a connection to the "server" (either by dialing
a telephone number with the modem, or just having
a direct physical RS-232 connection to the "server").
 Once the person establishes the connection to the
"server", he can execute a "client" program to
get the SLIP or PPP operation going -- perhaps
by explicitly typing "slattach" (or whatever)
at a "sh"/"csh"/"tcsh" shell prompt.
 Now (and this is the fuzziest part of my guesses
so far) the person's PC behaves just as if it
were on the Ethernet. If a program like "Mosaic"
is executed on the PC, it can access the INTERNET
through the host "server", provided that the host
machine is connected to the INTERNET.
--------------------------------------------------------------------------- Okay, almost everything I have written is speculative because it is difficult I am willing to re-write my little outline above to help future SLIP/PPP People sometimes refer to NET2-HOWTO as a source of information. I thought
to find an easy-to-understand description on the whole SLIP/PPP thing.
Most of the people posting to this newsgroup seem to know all about SLIP and
PPP, and their questions involve performance issues or freak problems;
but I am totally fresh to this game, and I need massive help.
newbies, and so I would be grateful for any contributions you can make
concerning each of my many vague impressions. Again, it can be turned in
to an evolving FAQ.
I was reading that file one day, but I was either reading something else or
I was completely bewildered. In any case, I would like to know where copies
of this file can be found.
Okay, almost everything I have written is speculative because it is difficult
I am willing to re-write my little outline above to help future SLIP/PPP
People sometimes refer to NET2-HOWTO as a source of information. I thought