The Best Internet Programs

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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.