 Getting A Connection

Direct TCP/IP - remote - SLIP - PPP - ethernet - parity -
flow control - unix - VAX/VMS - AIX - % - : - > - $...

There is a bewildering technobabble when it comes to con-
necting to the Internet.  This lesson attempts to simplify
this complex issue.  It tries to keep the discussion 
focused on just what you need to know and how to go about
connecting.





 Types Of Connections: Direct Or Remote 

The fastest Internet connection will be a direct one.  You
have one of these if your computer is part of a network
(usually an ethernet network) which is connected directly
to a computer that is on the Internet.

If you do not have a direct connection you may connect to
an Internet host via modem.  This is a remote connection.
Remote connections may utilize a system called SLIP or 
PPP (more later) which makes them seem to be attached dir-
ectly.  Or they may simply be dialed in (through a remote
terminal server) to a host Internet computer.  No special
software is needed for this latter type of connection.

 SLIP Or PPP 

There are two types of modem connections.  One uses SLIP
(Serial Line Internet Protocol) or PPP (Point to Point 
Protocol) which are fairly complex and requires 1) SLIP
or PPP software installed and running on your PC or Mac;
2) Connection to an Internet host computer running SLIP
or PPP server software; 3) a high speed modem.  The advan-
tage of SLIP or PPP are that your computer will act as
if it is directly connected to the Internet as long as
your telephone connection is maintained.  The disadvantages
are that SLIP and PPP are difficult to install and config-
ure, and if you are using them through a commercial provider
they are more expensive than a simple modem connection.

 Common Modem Connections 

The most common remote connection is via a modem and commun-
ications software in your own PC or Mac.  You must dial in
to an Internet host computer.  Speeds can be no faster 
than the speed of your modem and services can be no more
than provided by your host.

Since this is the most common type of connection for the
average user, this tutorial concentrates on it.  It's
disadvantages are slower speeds, and the limitations of
your host.  Advantages are ease of use and configuration.



 So How Do You Connect? 

If you are lucky enough to be a student or staff at a College
or University, work for a somewhat large company or govern-
ment agency, you are probably already on the Internet.  Your
computer is probably connected to an ethernet network
attached to a computer that is on the Internet.  Ask your
network administrator how to get started.

If you are not so lucky you will need to get an account with
an Internet provider.  A simple modem dial in connection 
will probably cost about $20 per month plus phone charges
(if it is a toll call to your provider).  A SLIP or PPP
connection will cost more.

 How Do I Find A Provider? 

Of the large commercial providers only Delphi offers full
Internet services.  America Online offers partial services
and is rushing to go to full service.  The other large
online companies offer only mail gateways, but look for
this to change soon.

There are many companies, however, whose sole business is
to be an Internet provider.  The "Internet Resources"
section of this tutorial has a feature which allows you
to enter an area code and it will return the name(s)
of potential local providers.


 Modems 

The world of modems (and the communications software that
drives them) can be very confusing.  There's nothing like
trying to install a modem in a computer that is already
attached to several serial devices.  You may have to set
jumpers on circuit boards, flip dip switches to assign port
addresses, assign IRQs to competing devices, select the cor-
rect cabling with the correct terminators, set up a cryptic
"modem initialization string," learn the Hayes AT command
set (at least part of it), and configure things like baud
rate, parity, stop bits, data bits, duplex, compression,
etc., etc.  If you are not discouraged yet, you should at
least be wary.  Modems can drive you up a tree.

 Do It Yourself? 

You may be one of the few lucky souls who have no serial 
devices attached to your computer, except perhaps a mouse.
In this case, simply purchase your modem, plug it in to
COM2 (or the port with the little picture of a phone on the
Mac), follow the simple directions for installing your soft-
ware, and dial in.  If, however, you have a mouse, a label
printer, a scanner, a laser disc player, and a couple
printers hanging off your computer, it's time to call for
professional help.  You'll end up ahead in the long run.
If your somewhere in between, you can do it yourself, but
be prepared to read a couple of unintelligible manuals and
have a bottle of tranquilizers nearby.

 Rules Of Thumb 

Here are some rules of thumb regarding modems:
  1) External modems are better than internal modems, because
     they have front panel lights that can tell you what is
     going on, and they have an on/off switch which you can
     use to reset the modem when things go wrong.
  2) If you buy a modem, buy a high speed one--14,400 bps.
     Accept nothing less.  Even if you are only planning to
     use the Internet for email, you will appreciate the 
     higher speed.
  3) Don't worry about all the techno-weenie terms like 
     V.32bis, MNP5, V.42, etc.
  4) Buy a name brand modem which is fully Hayes compatible.

 Communications Software 

If you purchase a modem it will usually come packaged with
communications software.  The best such package we have seen
is the US Robotics 14,400 Sportster modem which comes with
a DOS version of Crosstalk Communicator by DCA Corp.  There
are many other excellent packages, but there are also far
more inadequate, low-ball packages.  As a minimum be sure 
the communications software you get supports the full Hayes
AT command set and the Zmodem file transfer protocol.  Don't
worry about all the fancy terminal emulations.  All you will
need is VT100 (or one of it's later kin like VT102, 220, 320),
and maybe an IBM 3270 emulation.  Initialization strings can
be a big problem, so be sure there is a simple Hayes string.

 Pitfalls 

Be aware there may be alligators lurking in your modem waters.
If you have call waiting, you will have to learn how to dis-
able it.  If you already have a fax machine and answering
machine on your phone line, you may need another phone line.
If you have an especially "dirty" phone line you may have  to
pay to get a "clean" data line.  Nevertheless, in spite of all
the daunting things said so far, modems are essential unless
your Internet connection is a hard wired one as part of an
existing computer network.  Just don't underestimate the task
of setting up your modem, regardless of what the salesman 
tells you.  It's best to have a friend who knows modems.


 Settings 

Let's assume you get your modem installed just fine.  Here
are some settings that are pretty standard.
  Speed (bps) = As high as your modem will support.
                Set it initially to 57,600, a good modem will
                take care of the details.  This speed usually
                refers to communications between the modem and
                it's serial port.  Reduce this number if you
                are having problems.
  Parity      = None
  Data Bits   = 8
  Stop Bits   = 1
  Duplex      = Full

 Final Advice 

If you have to dial out through a pbx, you will have to change
your setup to allow your modem plenty of time to complete the
call.  This may also involve some trial and error in inserting
pause commands (commas) in the dialling string.  Choose Zmodem
as your file transfer protocol, but be familiar with Kermit
as well.  Sometimes it is the only thing that will work.

And one more thing...Good luck!


         
       

 Are We Having Fun Yet? 

Let's get down to business.  Is everything set up correctly?

     -- Computer working ok?                         
     -- Know your user ID and password?              
     -- Modem set up correctly?                      
     -- Communications software installed correctly? 
     -- Full of optimism and boundless energy?       

Let's Log In...




 Ricky Don't Lost That Number 

Oh yeah.  You need one more thing.  A phone number.  Usually
an internet provider has a range of numbers you may call. 
If the first doesn't get through, the system cycles up to 
the next.  Sometimes things get hung up, though, so it is
a good idea to know the range of numbers and instruct your
communications program to dial them sequentially until you
make connections.






 What's That? 

If you're a modem beginner, the first thing you'll notice is
that modems make lots of sounds.  You'll hear the dial tone,
the touch tone sounds, the office pbx (if you're in an
office), the shush and high pitched syncronization tones, 
and finally an alarm (usually) your communications software
issues to let you know you're connected.  The lessons that
follow imitate these sounds, but you can turn them off
(if you're a killjoy) by pressing the F5 key when you see
the F5 symbol at the bottom of the screen.

The screens you will see are from an actual internet source,
so pay attention.  These are skills you will actually use.

 Dialling Speeds 

The first time you dial in, this program will simulate a
modem attached at 2400 bps.  Later sessions, you will 
notice, go a lot faster.  Your temporary password
(unless you have already changed it using the Password
lesson) is 99friday.  Better write it down.  Enter it
when prompted.

Press D to dial in...





 Points To Remember 
Here are some things you should remember:

     -- Write down your user ID and keep it handy.  If you
        haven't logged in in awhile you may forget it.

     -- This goes double for your password.  Except don't
        keep it where anyone else will find it.  IF YOU
        FORGET YOUR PASSWORD THERE IS NO HOPE FOR YOU.

     -- When you type your password it will not echo
        to the screen (so someone can't peek over your
        shoulder and gain access to all your darkest
        secrets).

 Open Sesame 

So far we have logged in using a standard password.  Pass-
words are very important in order to insure the privacy and
security of your data.  One of the first things you should
do after getting your Internet account is to change your
login password.  In fact, some systems force you to change
the password the first time you log in.







 No Echo 

When you press a key on your keyboard, the corresponding 
character appears on your screen.  In computerese we say
the character "echos" to the screen.  You will notice 
when typing your password, however, that the characters
do NOT echo to the screen.  This is to keep your password
secret, in case someone is peeking over your shoulder as
you type.  The disadvantage is that you often cannot tell
when you have made a typing error, so type carefully.
If you don't enter your password just right, the system
will tell you so.



 What Can Go Wrong? 

Remember, a secure password is the only thing that keeps your
files private and safe.  If someone learns your password he/
she can log in to your account, read your private mail, damage
or destroy files, send bogus mail in your name, and do all
sorts of mischief.  Therefore, it is a good idea to change 
your password every few weeks, even if you are sure no one
else has learned it.  Some people develop elaborate cycles
of passwords that they use throughout the year.
  




 Password Suggestions 

On Unix systems you are encouraged to mix numbers with letters
in creating a password that is not easily guessed.  A couple
familiar numbers coupled with the name of an animal is a good
formula, but do what is most easily remembered for yourself.
Remember, Unix is case sensitive, so your password will also
be case sensitive.  

We are going to practice changing your password now.  Remember
the standard password for this program is 99friday.  If you
change it now, you will have to use the new password for the
duration of this session (unless you change it again).


 Terminal Emulations 

When dialing in to an Internet host computer, the host treats
your computer as a simple dumb terminal.  That is, your com-
puter becomes a work station that has no intelligence of it's
own but simply relays input from the user to the host and 
output back from the host to the user.  In fact, your PC or
Mac has lots of intelligence of it's own, but it's intelli-
gence would only get in the way when it is required to act
like a dumb terminal, so programs have been written to make
your computer "emulate" a dumb terminal.  It is the job of
your communications program to run this terminal emulation
program so that you can talk back and forth with the host.


 VT100 

There are a wide variety of terminals, and many host systems
will give you a choice, but the standard is called VT100.
Configure your communications program with VT100 when it
asks you what terminal you wish to use when dialing in to
your Internet host.  Vt100 emulates the VT100 terminal
made by Digital Equipment Corp.  (Actually it is no longer
made, but it's codes remain).  Your communications program 
may give you choices like VT102, or VT320.  Choosing any
of them is fine, just so they include all the VT100
control codes.



 Initializing Terminal Type 

When you log in to an Internet host, you will need to init-
ialize the terminal type for your session (unless the host
does it automatically for you).  Depending on the Unix 
shell you are using, you will need to type a command like
"set term=vt100," or set TERM vt100.  If your screen looks
scrambled when using a program like Pine or Gopher, it is
because you have not initialized your Unix terminal 
session to VT100 or you are not emulating VT100 in your
communications program.The VT100 standard is so important
to Internet communications that you should add a line to
your login script which willautomatically initialize your
session to VT100.

 Other Emulations? 

Even though your communications program will offer you a
wide variety of terminal emulations, stick with VT100.
Certain systems you telnet to may require you to emulate
the IBM3270 terminal.  You do not have to actually change
the emulation within your communications program to do so.
Instead of using the telnet command use the Unix tn3270
command instead, and everything will be ok.

Even though this sounds very confusing, keep it simple.
Learn how to add a command to initialize your terminal
session to vt100 when logging in and don't worry about
it any more.

 Unix Shells And Prompts 

A Unix "shell" is the command processor that Unix runs
which enables you to enter commands and execute programs
from your terminal.  It is equivalent to command.com
in DOS, and DOS's C:> prompt is replaced by a prompt in
Unix which looks different depending on which Unix shell
you are using:
  %              if you are using the C-Shell
  $              if you are using the Bourne Shell
  [userid@host]  if you are using the K-Shell

When you see the Unix prompt, it means Unix is ready to
receive your commands and act upon them.

 Other Prompts 

You will notice while using Unix that many programs have a
prompt of their own.  When you use the telnet program it's
prompt will look like this: telnet>.  Running ftp will change
your prompt to:  ftp>.  If you start the Kermit program your
prompt will change to: Kermit>.  When the prompt changes, the
normal Unix commands no longer apply, and special commands
understood only by that program may be used.  When you exit
the program, the Unix prompt will return.





 Get Used To It 

For those of us used to dealing with the DOS prompt, Unix is
not that great a leap.  If you come from the Mac world,
though, or use MS Windows exclusively, Unix will take some
getting used to.  Remember, it's not difficult.  It just
takes practice.
























