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- MacTCP and related Macintosh software
- =====================================
- revision 1.2, March 10, 1993
-
- ----------------------------------------------------------------
- Copyright Eric Behr, Illinois State University, Mathematics
- Department
-
- This document can be freely redistributed in whole or in part,
- provided that this copyright notice is included intact, and that
- no material profit is generated from such a transaction.
- ----------------------------------------------------------------
-
-
- With sincere thanks to:
- David N. Blank-Edelman dnb@meshugge.media.mit.edu
- Steve Dorner sdorner@qualcomm.com
- Patrick Hoepfner hoepfner@heasfs.gsfc.nasa.gov
- Peter N. Lewis peter@cujo.curtin.edu.au
- David S. Saunders dave@intercon.com
- as well as to several contributors to Usenet newsgroups, and to
- all those who sent me corrections and suggestions (but I'm the
- sole author of all mistakes, omissions and inanities)
-
- Please send all comments and suggestions to behr@math.ilstu.edu or
- to ejbehr@rs6000.cmp.ilstu.edu. The newest version of these notes
- can be obtained by anonymous ftp to spider.math.ilstu.edu, or
- 138.87.132.21 (file /pub/mac/mac-tcp.txt), or from a gopher server
- on the same computer (directory "Various documents").
-
- ----------------------------------------------------------------
- Changes from revision 1.1:
-
- - generally brought the document in sync with MacTCP 1.1.1
- - dropped remarks applicable specifically to MacTCP 1.0
- - changed the paragraph about MacTCP being bundled with certain
- free applications
- - changed the description of "disappearing LLAP icon" problem
- - mentioned apparent conflict with Super ATM
- - Telnet 2.5+ now uses MacTCP or internal drivers
- - modified description of LeeMail somewhat
- - added separate section on gopher
- - mentioned ircle, motd, tardis, hytelnet, archie
- - added Webster's e-mail address and US phone
- - updated the list of software on sumex
- - mentioned DiskCopy
- - mentioned Mac PPP, CCL and Calypso
- - added pointer to SLIP info on ftp.bio.indiana.edu
- ----------------------------------------------------------------
-
- CONTENTS
-
- PREFACE
- I. General stuff
- II. MacTCP
- III. Applications
- IV. Sources
- Appendix A. Peculiarities of Mac file transfers
- Appendix B. Elements of Macintosh networking
- Appendix C. Dial-in access
-
- PREFACE
-
- Judging by questions and pleas for help, more and more people
- are playing with MacTCP, and some of them are having problems
- installing and configuring it.
-
- I've spent many hours installing MacTCP on various Macs. I also
- devoted a large part of my free time to digging up various useful
- applications for use on the Internet. Hopefully some of my
- experiences will be helpful to you.
-
- Please note that I'm not a networking expert. Some of the advice
- below simply stems from my paranoia and is not necessarily based
- on facts. There are many problems with MacTCP which I don't fully
- understand. In addition, please remember that I'm not a technical
- writer, and my style may not be to your liking - sorry about that.
-
- Those readers who are new to the field of Macintosh networking
- might get something out of Appendix B -- please look at it before
- you continue.
-
-
- I. General stuff
-
- 1. Let's begin with a short sermon
-
- I started using the Internet several years ago, and it has
- become an important part of my life - for better or worse. I know
- that many people share my feelings about it. For the sake of all
- of us, please be considerate! There are lots of things you can
- mess up if you don't know what you are doing. Connecting your
- computer to the network which spans continents and is used by
- millions of people in their work is (or at least should be) a
- serious act.
-
- Please follow this simple advice:
-
- o when in doubt, don't do anything without consulting your
- local knowledgeable system administrator -- chances are that
- if you don't, you will break more than you'll fix;
-
- o find out how to access the Internet documents (esp. RFC's) and
- read the relevant ones before doing anything tricky;
-
- o read newsgroups such as comp.sys.mac.comm, comp.sys.mac.system,
- comp.sys.protocols.tcp-ip, comp.protocols.appletalk, especially
- the Frequently Asked Questions collections which are posted in
- most newsgroups from time to time;
-
- o read the flaming manuals!
-
-
- 2. Where does the Mac fit in?
-
- The Mac has always been a wonderful network machine. But for
- most people "Macintosh networking" means Apple's proprietary
- system called AppleTalk. The Internet uses a different networking
- "language". A major part of it is the protocol known by its
- acronym TCP/IP. To access the wonders of the Internet, a computer
- must understand TCP/IP.
-
- Even though there are other ways to make the Mac speak TCP/IP, we
- will concentrate on the most popular and orthodox one, namely the
- "MacTCP driver" from Apple.
-
-
- 3. Various connection methods
-
- The necessary software is only one part of a network
- connection. The other, obviously, is suitable hardware. A
- Macintosh can be connected to the outside world in many ways:
-
- o with a LocalTalk or PhoneNet connector (all Macs)
- o with a modem and suitable software (see Appendix C)
- o with an internal Ethernet card (Mac SE and newer)
- o with an external SCSI Ethernet adapter (all Macs)
- o with an internal TokenRing card (Mac SE and newer)
-
- Until recently MacTCP was not compatible with the last method of
- connection listed above. In mid-1992 Apple announced a Token Ring
- extension for use with MacTCP 1.1 and later, which does the trick.
-
- The problem of providing reliable and convenient dial-in access
- would require a separate book. A short note on this subject is
- found in Appendix C.
-
- Macs on Ethernet can usually connect to the outside TCP/IP world
- without a problem; for a long time TCP/IP has been the protocol of
- choice on Ethernet networks.
-
- Macs on LocalTalk can communicate with the outside TCP/IP world
- only if the LocalTalk is connected to a larger network using an IP
- gateway such as FastPath (Shiva), Gatorbox (Cayman Systems),
- Multiport Gateway (Webster Computer Corp.), EtherRoute/TCP
- (Compatible Systems), or one of other equivalent devices; or if
- such a gateway is present elsewhere on your internet, and is
- visible to your Mac. None of the software routers like the Apple
- Internet Router or Liaison (Inphosphere) currently provides TCP/IP
- services, so if that's what you use to connect to an Ethernet, you
- must also have a gateway which will translate the IP packets
- wrapped in AppleTalk (which your LocalTalk Mac sends) into genuine
- IP packets going to the outside world, and vice versa. We briefly
- describe some of the details in Appendix B.
-
- Please note that AppleTalk and TCP/IP are two completely different
- animals, even though a single Mac can use both at the same time;
- configuring AppleTalk functions, such as printing over the network
- or AppleShare, will not be discussed here.
-
-
- II. MacTCP
-
- 1. How to get it?
-
- MacTCP (version 1.1.1 as of this writing; version 2.0 will be
- released soon) is marketed by APDA (408 974 4667). Don't expect
- your local Apple dealer to know much about it. Current price of a
- single copy is about $100. A site license is available, and some
- institutions may qualify for discounts. Call APDA. If you already
- have an old version, you should have no problems upgrading to the
- current one.
-
- Some public domain TCP/IP applications used to come bundled with
- MacTCP. Developers used to pay Apple a rather stiff fee for a
- "distribution license". Apple has recently changed the rules in
- this area, significantly increasing those fees. The situation is
- still a bit murky, but it seems that it is impossible to obtain
- the newest version this way. MacTCP 1.1 can still be found bundled
- with older applications (e.g. Eudora 1.2.2). Note that MacTCP 1.1
- will not work reliably, or at all, with System 7.1 or newer.
-
-
- 2. What is it?
-
- For the user, it is a Control Panel, configured just as the
- Monitors or Sound panels. For applications, it is a set of
- procedures which allows them to communicate with other hosts on
- the network using the TCP/IP protocol. It is designed to be
- transparent in the sense that once it is properly configured, any
- correctly written application can make use of it without user
- intervention. Granted, life without MacTCP would be hell! In
- practice however, both MacTCP and the applications which use it
- have idiosyncrasies and bugs which make this software difficult to
- handle. In my own experience, the Mac SE is the most unstable
- MacTCP platform, probably because of the peculiarities of its
- ROMs; but I admit that it is a statistical observation, with no
- theory at all to back it up.
-
- Apple, in all its charming inconsistency, tells us to use their
- Installer even when adding a silly little printer driver, but at
- the same time does not provide an Installer script for the rather
- intricate procedure of installing and configuring MacTCP.
-
- Here's the way I've successfully done it on many machines. These
- are purely empirical findings, so treat these procedures more like
- a rain dance than a rational troubleshooting guide.
-
-
- 3. Let's do it!
-
- If you are installing MacTCP for the first time, or if you
- suddenly run into problems such as the dreaded message "Error
- opening TCP drivers - possibly no dynamic addressing", you should
- follow these steps for maximum effect.
-
- My general advice is: start with virginal (or at least freshly
- updated) system files. Problems may result from improperly
- installed old version of AppleTalk or other resources. For
- example, I could never painlessly install new Ethernet drivers on
- any Mac which previously had drivers for the Nuvolink SC box
- installed on it (I don't mean to put down Nuvotech's products -
- they usually work fine). What's worse, some network applications
- seem to corrupt the System, and/or other important files, when
- they crash. So here we go:
-
- o This is almost certainly an overkill, but in some cases it is
- also a recipe for instant happiness. If you are having major
- problems, boot from a system floppy, and trash the following from
- the hard disk: System, Finder, Multifinder, MacTCP, AdminTCP,
- MacTCP Prep, MacTCP DNR, all network drivers and control panels
- (AppleTalk, EtherTalk, Network). These gadgets are found in the
- System Folder proper (in pre-7 Systems) or in various subfolders,
- such as Control Panels, Preferences and Extensions. Of course,
- you'd better first back up all the files which seem important to
- you, such as non-standard extensions or fonts, which will get
- erased in the process! Then install a fresh system.
-
- o Disable all INITs, and non-essential network-related CDEVs,
- especially those which may be requesting network services at boot
- time (such as Network Time). Again, this probably isn't necessary,
- but who knows... As is well-known, many INITs produce mind-
- boggling conflicts. When you succeed in making MacTCP work without
- them, you should later reinstall them one by one, checking - say -
- telnet after activating each of them. If MacTCP conks out, you'll
- know the culprit! If that happens, please publicize your findings,
- or at least send a note to me.
-
- o If you will be using MacTCP over Ethernet, install network
- drivers according to manufacturer's instructions. For some reason
- I had better luck when I turned off AppleTalk in the Chooser
- before doing this. If you are installing Apple's drivers, make
- sure to use the latest Network Installer disk.
-
- If you will be using MacTCP through the serial (printer) port,
- activate AppleTalk in the Chooser now. Some Ethernet drivers, and
- the MacTCP Token Ring extension, also require AppleTalk to be
- active for MacTCP to work.
-
- o Configure the network drivers, if necessary. Most Ethernet
- drivers have no user-changeable settings at all. The Token Ring
- driver (configured via its Control Panel) should be set for the
- correct speed (4 or 16 Mbps). It also lets you set the hardware
- address of the adapter; if your site uses locally administered
- addresses, you need to get one from a local administrator, and set
- the driver accordingly.
-
- If you need your Mac's Ethernet hardware address for debugging
- purposes or simply for your records, you can get at it by holding
- option down while clicking the "Ethernet built-in" icon in the
- MacTCP panel. Another method is to log on to a nearby Unix
- machine, do a "ping" to your Mac's IP address, and then tell the
- Unix host to list its "ARP cache": arp -a on most systems. The
- hardware address will appear next to your Mac's name as 12 hex
- digits divided into pairs.
-
- Remember that Ethernet and Token Ring handle hardware addresses
- differently; if the Unix host and the Mac are on those two
- different types on networks, you need to translate each pair of
- hex digits into 8 binary digits, reverse their order, and
- translate the whole shebang back into 12 hex digits to get the
- real hardware address.
-
- o Put fresh MacTCP, AdminTCP in the System folder. Make sure that
- you are using the newest version, and not some old copy obtained
- from shady sources. Under System 7+, they will go into the proper
- subfolder automatically if you drop the files on top of the System
- Folder icon.
-
- o In the next few steps in our procedure, MacTCP will create two
- files: MacTCP DNR and MacTCP Prep (under System 7 the latter
- should end up in the Preferences folder). You did remove the old
- ones, didn't you? Since some virus protection utilities might
- think that the new files that MacTCP is installing in the System
- folder are viruses, it is a good idea to shut off all virus
- protection before you go any further.
-
- o Configure MacTCP or AdminTCP (you will find more about that in
- later sections). Make sure you set the right network class and
- subnet mask if you use static addressing. You don't have to worry
- about that if you use a server such as FastPath or EtherRoute/TCP
- to assign addresses. For the time being, don't do anything with
- the "gateway" (should be 0.0.0.0) and "nameservers" (blank)
- fields.
-
- o Remember to set the correct physical layer setting ("Ethernet
- Built-in", "LocalTalk", or "Token Ring") in the MacTCP panel (if
- it gives you that choice).
-
- Let me reiterate that the physical link setting has nothing to do
- with the network resource (selected in the "Network" CDEV) which
- you will be using for AppleTalk functions, such as printing or
- AppleShare: we're dealing with strictly TCP/IP stuff.
-
- If your Mac is using a direct Ethernet connection for TCP/IP, you
- normally *don't need to* (nor should you, in some specific cases)
- activate AppleTalk or choose anything in the Network CP at this
- point. As we mentioned before, there are exceptions to this: some
- Ethernet drivers, and the MacTCP Token Ring extension, do require
- AppleTalk to be turned on in the Chooser.
-
- If you are using TCP/IP through the LocalTalk port, you must have
- activated AppleTalk in the Chooser before - otherwise that port is
- simply dead, and MacTCP doesn't know how to communicate with the
- outside world! On a Mac Plus, trying to reconfigure MacTCP with
- AppleTalk shut off will likely result in a horrifying "address
- error" or "illegal instruction" message. Don't worry - reboot,
- turn on AppleTalk and see if the new MacTCP settings are still
- there. If not, configure it one more time. Everything should be
- fine after that.
-
- o Even though MacTCP 1.1 doesn't always tell you to do so, REBOOT
- now! Check that MacTCP DNR (and usually MacTCP Prep) files show up
- in the System folder.
-
- o Older Macs, notably the Plus, become overworked while running
- System 7 (more precisely, the newest versions of AppleTalk) and
- MacTCP 1.1. Apple has released an unsupported patch which fixes
- the problem. You can get it from ftp.apple.com (see section IV,
- Sources, below). Do NOT install this patch unless: you have a
- Plus, *and* you run AppleTalk vsn. 56 or higher, *and* you use
- MacTCP 1.1. Another workaround is to use a SCSI Ethernet adapter
- instead of a LocalTalk connection; the SCSI port can handle this
- load, while the serial port controller can't.
-
- o Test MacTCP by running an application such as NCSA Telnet (the
- MacTCP version, of course). If the NCSA logo quietly disappears,
- you're in business. Try connecting to a *nearby* host by giving
- Telnet its decimalized IP address, such as 138.87.132.21.
-
- As of this writing, newest versions of NCSA/BYU Telnet sometimes
- produce a system error when they're run on a Mac Plus under pre-7
- System. This might indicate a serious problem, but in 9 cases out
- of 10 this happens only the first time you attempt to run Telnet.
- Reboot and try again.
-
- o Assuming all went fine, you can now set the AppleTalk link in
- the Network panel if you wish (if AppleTalk was off, that is; this
- should also automatically turn on AppleTalk in the Chooser, but
- check it just in case). There are some exceptions here. For
- example if your Mac is on Ethernet, which in turn is connected to
- a Token Ring with the IBM 8209 bridge, activating AppleTalk might
- screw up TCP/IP. Details available on request.
-
- o If you can't connect to remote hosts, check if the "default
- gateway" field in MacTCP changes from the original 0.0.0.0 to
- something else after you start telnet or other MacTCP software. If
- it doesn't, then your Mac is having trouble discovering a gateway
- which connects your LAN with the rest of the world. You need to
- tell MacTCP where it is: enter its numeric IP address in the
- "default gateway" box. You may also want to tell it where the
- local nameserver for the root domain is (put a period in the
- "Domain" field, enter the IP address in the box next to it, click
- Default). To be on the safe side, trash MacTCP DNR and MacTCP Prep
- again; be sure to reboot the computer.
-
- o You should now be able to telnet to a remote host, and Telnet
- should be able to resolve symbolic addresses for you: e.g.
- nic.ddn.mil or sumex-aim.stanford.edu.
-
- If after all this you are still having problems, first check the
- hardware (is Ethernet up? are plugs plugged in? switches switched
- on? gateways are gatewaying? etc) Next, consider the possibility
- that some other node is using your IP address. See if things work
- if you change the IP address to another one from the range
- assigned to you. When MacTCP loads, it in effect asks the network:
- "host with IP number so-and-so, please respond". Your Mac's IP
- address is used in that query. If there is no answer, all is good.
- But if something out there responds, MacTCP correctly assumes that
- there is a conflict in IP numbers, and returns an error code which
- most applications then translate to a less-than-helpful message
- like "MacTCP is not installed correctly", or "Error opening TCP
- drivers - possibly no dynamic addressing".
-
- If all of the above doesn't help, buy a pair of tickets to Jamaica
- and invite your high-school flame along. After all, will you let a
- piece of steenkin' iron drive you nuts?!
-
-
- 4. Details...
-
- In the description below, we use the MacTCP control panel. The
- only difference between it and AdminTCP is that the latter allows
- you to lock and unlock the former; other than that, they are
- functionally identical. If the MacTCP panel you have has been
- locked, you won't be able to make any changes to it; you have to
- unlock it with AdminTCP first, or simply make all changes from
- within AdminTCP.
-
- After opening the MacTCP control panel, you should first set the
- physical link for the TCP/IP connection; for instance, if you use
- MacTCP on a LocalTalk network - whether gatewayed to an Ethernet,
- or isolated - select the "LocalTalk" icon. If you are directly on
- Ethernet, click the "Ethernet Built-in" icon.
-
- Now click the More button. In the first stage, you will be setting
- only three things: address assignment mode, network class, and
- network subnet.
-
-
- - If you are a "trusted and permanent" user who received a
- specially assigned IP address, click the "Manually" radio button.
- As a rule, it is best to have a permanent, static IP address. Some
- networks, however, have more nodes than addresses available to
- them. Such institutions resort to assigning addresses dynamically
- to those hosts (usually PCs) which request them; see the next
- subsection.
-
- Please remember that choosing an address at random will at best
- make your connections unreliable; it can also provoke unrestrained
- wrath of some powerful people in your organization. Courts have
- been known to drop bodily harm charges under much weaker
- extenuating circumstances. Moreover, some network numbers are
- illegal on the Internet. If you pick one of those, you'll be
- asking for a lot of trouble - in particular, you'll be getting all
- e-mail addressed to the University of Mars for the rest of your
- life.
-
- o The IP number you were assigned determines the network class.
- MacTCP is smart enough to figure it out by itself. You can also
- set it manually: addresses beginning with 1-127 are class A, 128-
- 191 indicates class B, and 191-254 are class C. Make sure you know
- what you are doing.
-
- o The netmask can be determined by stopping a friendly
- administrator in the hall and asking one or two simple questions.
- "Do we use subnetting?" And, "If so, how many bits form the subnet
- number?" If the first answer is "no", then slide the subnet mask
- indicator as far to the left as it will go. Such masks are
- 255.0.0.0 for class A networks, 255.255.0.0 for class B, and -
- guess what - 255.255.255.0 for class C.
-
- If your site does use subnets, the plot thickens. A number of
- address bits is set aside as the subnet number. You have to enter
- the subnet mask (such as 255.255.255.0, eight bits determining the
- subnet in a class B network) in the appropriate field; or you can
- delicately slide the subnet indicator to the right until it marks
- the right place. For example, if 6 bits are reserved for the
- subnet, you slide the thing from the leftmost position to the
- right by six little notches.
-
- Be forewarned: it is vital that all hosts which have the same
- network part in their address use identical subnet mask. You can
- avoid a lot of desperation in the future if you make sure you get
- this straight. 'Tis the time to read the manuals, perhaps?
-
- o Get out of the "inside" panel by clicking OK. Type your IP
- address in the edit field in MacTCP. Go back to the subpanel to
- verify everything is as it's supposed to be. If anything has
- changed all by itself, you are probably trying to set a wrong
- network class.
-
-
- - If you were told that "dynamic address assignment" is available
- to you, then all you need to do is click the Server radio button
- in MacTCP. Things should work automagically thanks to built-in
- intelligence of devices such as the FastPath, GatorBox, or
- EtherRoute/TCP. If there are problems, you have to get together
- with the person who maintains your gateway.
-
- - Many people prefer to avoid the "dynamic" button in MacTCP.
- Others have been using it successfully. There are situations when
- Apple's "dynamic addressing" is called for, but don't use it
- unless you have to.
-
-
- After you have entered all the required information, and you
- suspect that the user has itchy hands, it's time to click the
- "protected" box, close the panel and reboot right away. Remember
- to trash AdminTCP from his disk after you are done setting things
- up.
-
- If the user is likely to heed your advice, but might accidentally
- change the settings, click the "protected" box in AdminTCP, tell
- him not to fiddle with AdminTCP, and leave the control panel on
- his disk. This will save you some time and trouble when you have
- to change his settings again.
-
- If the prospective user is a TCP/IP sage, then you of course leave
- things wide open for him to play with the little buttons during
- long winter nights.
-
- There are some other permutations involving, for example, locking
- just the network part of the address, but leaving the subnet and
- node numbers accessible. Please read the manual!
-
-
- 5. More details
-
- After you have coerced MacTCP to work with this basic
- configuration, you may want to enter a few more things.
-
-
- The "Gateway Address" field in the MacTCP control panel should
- contain the IP number of the default gateway, i.e. the place where
- MacTCP should send packets if it doesn't know what else to do with
- them (i.e. packets addressed to a remote network). On most
- networks you will leave that field set to 0.0.0.0, and MacTCP will
- locate the default gateway by means of a magic wand called Routing
- Information Protocol (RIP).
-
- If your network for some reason does not implement RIP, you must
- enter a "real" address there. For example, if your Mac is on
- LocalTalk, you would use the address of a FastPath or another
- device which connects your network with the Ethernet. If you are
- directly on Ethernet, you should use the address of the router
- which connects that Ethernet to the campus network, or - if you
- don't have routers - the gateway which links your outfit with the
- rest of the world.
-
-
- You will also want to tell MacTCP where to find nameservers. Going
- into the details of the Internet Domain Name System (DNS) would
- make this document twice as long, so we will stick with the
- basics. The Domain Name System is used by computers to convert the
- human-friendly names such as "spider.math.ilstu.edu" to numeric
- addresses (IP numbers) such as 138.87.132.21. On occasion,
- computers use this system to "reverse-map" numeric addresses, i.e.
- to verify that your numeric address does correspond to a name
- which recognized by the DNS.
-
- If your network is connected to the Internet, your computer lives
- in some well-defined "domain". In my case, it is math.ilstu.edu,
- and a machine with address 138.87.132.21 is providing name service
- for that domain. I thus enter "math.ilstu.edu." (no quotes, but
- note the period at the end!) in the Domain field, and
- 138.87.132.21 in the Server field next to it. I also click the
- Default button. This informs MacTCP that my computer is in the
- math.ilstu.edu domain, so when I tell my Mac to telnet to "koala",
- it will query the nameserver about the address of the computer
- "koala.math.ilstu.edu". Here is the first row of edit fields on my
- Macs:
-
- --------------------------------------
- | math.ilstu.edu. | 138.87.132.21 | x | ("default" button on)
- --------------------------------------
-
- If the local nameserver doesn't keep a large table of addresses,
- or if it is less than reliable, you will probably want to put in
- some backup servers in fields below. In particular, one or more
- Domain fields could contain the period alone ("root domain", i.e.
- the entire Internet) with the address of a big, reliable machine
- next to it.
-
- Clicking the "default" button by no means guarantees that this
- particular server will be consulted first; MacTCP first contacts
- those nameservers listed in the control panel which seem to match
- the domain name included in the query - and only if that fails,
- the default server is asked as a last resort. However, all domain
- name queries should generally go to your local nameserver first.
- You may want to enter your local nameserver's address in the
- second row as well, specifying the root domain (period) in the
- first field. In my case, the second row would thus look like this:
-
- --------------------------------------
- | . | 138.87.132.21 | o | ("default" button off)
- --------------------------------------
-
- A small text file called Hosts can be put in the System Folder
- proper. I was told that some applications (e.g. VersaTerm)
- automatically create this file and modify it when needed. The
- Hosts file lets you enter additional information which MacTCP
- uses. For example, I could enter
-
- spider.math.ilstu.edu. IN A 138.87.132.21
- math.ilstu.edu. IN NS spider.math.ilstu.edu.
- rs6000.cmp.ilstu.edu. IN A 138.87.1.2
- rs6000. CNAME rs6000.cmp.ilstu.edu.
- ilstu.edu. IN NS rs6000.cmp.ilstu.edu.
-
- there to tell MacTCP that the computer spider.math.ilstu.edu has
- address 138.87.132.21, that it is a nameserver for my domain, that
- rs6000 in Computer Services has address 138.87.1.2, that I connect
- to it often enough so I want my Mac to use rs6000.cmp.ilstu.edu
- whenever I say "rs6000" (otherwise MacTCP would be looking for
- rs6000.math.ilstu.edu!), and that it is a nameserver for the
- domain directly above me.
-
- The use of periods at the end of domain names guarantees that
- MacTCP treats them as "absolute names", and doesn't try to append
- anything to them. If you know what you are doing, you can work
- with relative names (without the period) saving some space,
- typing, and quite possibly reducing the amount of memory MacTCP
- consumes. Assuming that my Macs are placed in the domain
- "math.ilstu.edu" by using the 'default nameserver' button in
- MacTCP, I could simply use "spider" instead of the absolute
- "spider.math.ilstu.edu.", because that extension would be
- automatically appended to a relative name without the period.
-
-
- For a list of specifications allowed in the Hosts file, see the
- MacTCP manual. I have also collected a few relevant Usenet
- postings in a file mac-dnr.txt, available by anonymous ftp from
- spider.math.ilstu.edu (directory /pub/mac).
-
- After modifying the Hosts file or the nameserver information in
- the MacTCP control panel, make sure to trash the MacTCP DNR file,
- and reboot right away.
-
-
- 6. Odds and ends
-
- We end this section with a few miscellaneous problems reported in
- Usenet newsgroups or in personal communication.
-
-
- Sometimes the physical link icons (usually the "LocalTalk built-
- in" icon) mysteriously disappear from the MacTCP 1.1 control
- panel. This problem is fixed in the current version of MacTCP. If
- you are still using 1.1, read on. If the MacTCP panel does not
- show any choices at all, it might help to zap the parameter RAM by
- holding down:
- command-option-p-r while restarting the mac (system 7)
- command-option-shift while opening the Control Panel (pre-7 systems)
- (reported by Mike Wiese of MIT in a Usenet posting). I haven't had
- much luck with this fix. Running System 7 and the TuneUp extension
- on a Mac broken in this fashion, I found that I had to reinstall
- the system and network files from scratch, then install, configure
- and test MacTCP, and finally install the TuneUp as the last step.
-
-
- One of the gizmos with which our users are currently having
- problems is Adobe's SuperATM (which advertises its serial number
- on the network, and in the process appears to choke MacTCP). I
- don't have a solution for this.
-
-
- Don't disregard the physical connection. I've seen several reports
- of strange problems which were eventually traced to a bad wire or
- transceiver. Some of Apple's "FriendlyNet" cables for use with the
- Quadras were involved. Borrow a working transceiver and cable from
- someone and try it before blaming everything on the software.
-
-
- Are things messed up, and you are stuck? Make sure to contact the
- vendor of the network adapter. There may be a problem which they
- know about. You may need to get an updated driver from them.
-
-
- It was reported that the Apple cache card (for the IIci) used to
- cause problems with MacTCP and a lot of other things. Scream for a
- replacement!
-
-
- Some cases of MacTCP applications freezing some machines (notably
- older SE's) seem to be caused by bad karma between MacTCP and the
- system ROMs. Matthew D. Heys a while ago reported extensively on
- his experiments. He empirically demonstrated that the freezes
- happen after a "cold start" (i.e. powerup), but do not occur after
- the computer is restarted with the programmer's switch or with the
- "Restart" in the Finder's "Special" menu. This may or may not be
- fixed in MacTCP 1.1.1 -- I haven't heard one way or another.
-
-
- III. Applications
-
- There are many commercial programs which use TCP/IP connectivity
- (InterCon's family of networking applications, or VersaTerm from
- Synergy Software). I will not review them here because I have had
- little or no experience with them. Let the vendors speak for
- themselves. Some makers of similar commercial products are
- mentioned in Section IV for your convenience.
-
- The list of public domain or shareware software which follows will
- hopefully be amended and expanded in the near future - please send
- in your favorites!
-
-
- 1. Terminal emulation
-
- There are currently two popular freely available programs which
- let the Mac connect to other hosts as a terminal using TCP/IP
- (telnet): NCSA Telnet and its derivative, tn3270.
-
- The first one is being developed at the National Center for
- Supercomputing Applications in Urbana-Champaign. It emulates a
- vt100 terminal and provides some Tektronix graphic terminal
- capabilities; it also implements an ftp server function, i.e. when
- it's running, you can ftp *from* other hosts *to* your Mac. NCSA's
- version was modified somewhat by the Brigham Young University;
- NCSA/BYU Telnet implements a simple ftp client function.
-
- The second, tn3270 written at Brown University, is a variant of
- Telnet which provides the IBM 3270 terminal emulation. It also
- supports file transfers and printer sessions, but I don't know
- enough about our IBM big iron to actually try them out...
-
- NCSA Telnet used to come in two versions: one which relied on
- MacTCP, and one which included built-in TCP/IP drivers. Starting
- with Telnet 2.5, the two have been merged into a single package.
-
- Stanford University has developed a comprehensive package of
- TCP/IP applications collectively known as SU-Mac/IP. I didn't have
- a chance to try it. One advantage of Stanford's software is that
- it reportedly gives more informative error messages, which can be
- a great asset - especially when you are having problems! Contact
- macip@jessica.stanford.edu for conditions of a site license. If
- you know how to use MacBinary FTP, you can download the entire SU-
- Mac/IP documentation in MS Word format from jessica.stanford.edu
- (directory netinfo/macip/manuals4.0/users).
-
-
- 2. E-mail
-
- There are several schemes in which a Mac can access Internet mail.
- The crudest way, of course, is to telnet to a host on which you
- have an account, and use that host's mail facilities. Another is
- to keep using whatever mail system you have on the AppleTalk
- network (e.g. QuickMail or Microsoft Mail), and then provide a
- SMTP gateway which will translate it to Internet mail; this tends
- to be expensive and sometimes unreliable.
-
- By far the most popular and convenient system is the client/server
- method, in which one computer uses its powerful mail software and
- provides service to clients such as Macs or PCs. Macintosh users
- have the good fortune of being able to use some excellent mail
- clients which work on a Mac. Eudora written by Steve Dorner leads
- the pack (in my humble opinion), with MIT's Techmail a close
- second.
-
- Eudora and other similar clients allow the user to read, compose,
- and edit mail on the Macintosh desktop; it can print mail, save
- messages as Mac files, and attach Macintosh-specific files (say,
- formatted Word documents or even applications) to the letters
- using the Macintosh standard BinHex encoding scheme (see Appendix
- A). When it's time to process mail, Eudora contacts the server,
- uploads messages waiting to be sent and downloads those which the
- server received for you. The (supposedly) well-maintained and
- well-connected server computer handles the rest, so you don't need
- to know anything about Unix or any other alien operating system.
-
- A special "Post Office Protocol" has been defined to handle this.
- There are two versions of it: POP2 and POP3. The server and the
- client have to agree on the version they speak. Most Mac clients,
- in particular Eudora, are POP3. If you succeed in sending mail,
- but attempts to check incoming messages fail, then it is very
- likely that your POP client and server use different versions of
- the protocol.
-
- It is easiest to set up a POP server on a Unix computer (popper
- from UC Berkeley seems to be the way to go here), but there are
- also servers operating under other systems, including one (POP2)
- which runs on a Macintosh. If you use a VAX with VMS, and some
- TCP/IP package is already installed, chances are that it includes
- a POP server. There is also a public domain POP3 server for VMS
- available from Indiana University, which a dear friend of mine, a
- computer semi-literate, got up and running without much grief.
- Talk to your local system administrator.
-
- For those of us who need to worry about PCs too, POPmail from
- University of Minnesota runs on MS-DOS machines and is compatible
- with both POP2 and POP3. A POP2 server running on a Mac is also
- available from that site.
-
- A Macintosh mail client is also included in Stanford's SU-Mac/IP
- package, available for a nominal fee.
-
- In case you don't have a reliable machine which may be used as a
- POP server, don't worry; your Mac can be made into a full-blown
- SMTP mailer, and it then behaves like any other "real" Internet
- mail node. Lee Fyock's LeeMail does just that. Using it avoids the
- complications involved in maintaining a central mail computer, and
- in setting up a client-server system such as POP. Naturally, a Mac
- configured as an independent Internet mail host had better have
- reliable connectivity with the world at large (and a properly
- configured Domain Name Resolver).
-
- Finally, a Swedish offering - MacPost - is something of a mixture
- of both methods; it has both a client and a server running on a
- Macintosh, but requires a Unix host as an intermediary for outside
- mail. The transactions between the individual clients and a
- MacPost server only use AppleTalk, and TCP/IP is only needed by
- the server Mac to communicate with the Unix host. I haven't used
- this one either, but who knows - it might be just the thing for
- you.
-
- Steve Dorner occasionally posts his much more complete list of Mac
- POP clients (including commercial ones) to newsgroups such as
- comp.protocols.appletalk and comp.sys.mac.comm.
-
-
- 3. FTP
-
- As we mentioned above, Telnet has limited ftp capability. But two
- other applications, XferIt and Fetch, are specifically designed to
- provide "FTP with a human face". Both present the directory on the
- remote host as a Macintosh dialog window, in which the user can
- select files to be downloaded. I've found minor quirks in both of
- them, but overall they are extremely impressive and useful. There
- is also HyperFTP, a HyperCard stack which is similar to the two
- applications. It is very solid, but relatively slow, and -
- naturally - it requires a reasonably recent version of HyperCard
- and consequently quite a bit of RAM.
-
- As with telnet and mail, an ftp application is also available as
- part of the SU-Mac/IP software.
-
- When using FTP from a Mac, you should realize that many anonymous
- FTP sites do not allow connections from hosts which are unknown to
- the Internet nameservers. To connect to such nodes, your Mac's IP
- address has to "reverse-map" to a legal Internet name, like
- mac1.math.ilstu.edu. The system administrator of your nameserver
- computer might be willing to enter your address in his database.
-
- See Appendix A for a very short introduction to the intricacies of
- Macintosh file transfers. For more information on the procedures
- involved in FTP'ing Macintosh files, read the text file ftp-
- primer.txt, which is on sumex.stanford.edu in the directory info-
- mac/reports.
-
-
- 4. Network news
-
- As with FTP, there are three applications and one HyperCard stack
- designed to let you access news: TheNews, Newswatcher, NetNews
- (stack), and Nuntius. I have not experimented with Nuntius, so I
- can only quote second-hand information: at least one of my
- correspondents swears by Nuntius as "the best newsreader I have
- seen on the Mac by far".
-
- There are minor problems with each of the first three, compounded
- by the fact that this method of reading Usenet articles usually
- involves downloading humongous lists of articles over a slow
- connection such as overloaded LocalTalk, keeping track of read
- items, and so on. This is not for the faint of heart. Many people
- still stick to the old-fashioned method of logging on to a bigger
- host and reading news there. But when it works, it's worth it! You
- can finally organize the saved articles on your own disk, use your
- favorite word processor to write replies, etc. I hesitate to
- recommend specific choices, but personally I have found the newest
- NewsWatcher to be very stable, powerful and easy to use.
-
- News clients require an address of a nearby friendly NNTP server.
- The server needs to be friendly in the sense that it must
- recognize your Mac as a host which is allowed to post news. This
- usually requires having a valid domain name (see above under FTP),
- and the server must have been configured to accept uploads from
- your computer. Even though many servers allow free read access but
- limit posting, the Mac clients will usually give up without
- explanation unless they are granted both permissions. This causes
- a lot of confusion among novice users, who later complain about
- "broken newsreaders".
-
-
- 5. Internet Gopher
-
- The Internet Gopher searches "gopher servers" on various Internet
- hosts and retrieves various information such as directory entries,
- class schedules, campus newsletters, etc. One Macintosh client is
- a HyperCard stack written at University of Minnesota. It has been
- recently superceded by an application called TurboGopher, which
- definitely lives up to its name. Another standalone implementation
- is GopherApp from Indiana University.
-
- Gopher is quickly becoming the standard way of providing access to
- distributed information such as campus directories, WAIS servers,
- on-line publications, etc. It is also the preferred method of
- accessing many of the anonymous ftp sites, such as the sumex
- archive at Stanford.
-
-
- 6. Miscellaneous gadgets
-
- There are dozens of useful or simply nifty applications which use
- MacTCP. Here are two of my favorites.
-
- Network Time written by Peter Resnick is a CDEV which periodically
- contacts an Internet timeserver, like merit.edu or nic.ddn.mil,
- looks at the Map CDEV to determine your location (and hence time
- zone offset; I particularly like this elegant touch), and sets
- your Mac's clock. After installing it you can boast that your
- screen clock is accurate to a tiny fraction of a second.
-
- A Chooser extension called Tardis is functionally similar to
- Network Time. It uses a Timelord server running under Unix or Mac
- OS to set the time on networked Macs. Another Chooser device,
- motd, will access a Unix motd server, providing a very useful
- "message of the day" service. The servers on the Unix side rely on
- the CAP libraries. Both of these gadgets use AppleTalk rather than
- TCP/IP, so they really don't belong here, but I think they are
- useful enough to deserve a short mention. CAP, motd, and tardis
- are all available from munnari.oz.au (and many other places).
-
- Finger and fingerd by Peter Lewis give Macs the Unix "finger"
- capability. Finger sends a finger query to a remote host; it's
- even smart enough to automatically put people whom you "finger-ed"
- in a menu, so you don't have to type their address again. Finderd
- simulates a finger daemon on your Macintosh, so other people can
- finger you while you are simply working on your Mac.
-
- Peter has released another fine product - Talk, which simulates a
- Unix "talk" client and daemon on the Macintosh. Peter's latest
- product, ftpd, runs in the background under System 7 and turns the
- Mac into an ftp server.
-
- Those who are familiar with the Internet Relay Chat system will be
- pleased to see Chat (also by Peter Lewis), which is a simple IRC
- server running on a Mac. They will also want to try a full-blown
- IRC application, ircle.
-
- Wide Area Information Service is a fruit of a joint project of
- Apple Computer, Thinking Machines, Peat-Marwick and Dow Jones.
- There are several WAIS servers in operation; they can be queried
- from a Mac by means of an application called WAIStation. A WAIS
- server can also be accessed by telnet to quake.think.com (login
- name wais), but the interface is then much less friendly. Check it
- out! It's a glimpse at the things to come.
-
- MIT's TechInfo is another impressive example of a fast and easy to
- use information retrieval system. MIT and a few other institutions
- run servers which store and search databases of campus events,
- faculty and student directories, etc. Both Mac and PC clients are
- available.
-
- Unix users may be familiar with hytelnet ("Hyper Telnet"), which
- is somewhat similar in spirit to the gopher system. It provides a
- convenient way of exploring public Internet resources accessible
- by Telnet. A Macintosh implementation of hytelnet, based on
- HyperCard, can be requested by e-mail from Charles Burchill
- (burchil@ccu.umanitoba.ca).
-
- Thanks to Chris McNeil, we finally have a Macintosh archie client.
- It searches archie servers, retrieving from them information about
- the contents of anonymous ftp archives.
-
- If your Macs use the CAP AppleShare server, chances are you'll
- want to look at MacDump, which permits automated backups of your
- Mac volumes onto the CAP server.
-
- A desk accessory called Client DA (written by Greg Anderson of UC
- Santa Cruz) connects to the Unix daemon "supersrv" (by Steven
- Grimm), which in turn uses the wonders of Unix to do whatever you
- want it to do. For example, a trivial Unix shell script invoked by
- supersrv allows our faculty to search all users on the system, or
- access the archie ftp search facility directly from their Macs.
- Client DA has some problems with smaller Macs, and I wish someone
- kept maintaining this wonderful gadget.
-
- On the lighter side, we have GameMaster, which lets you play a
- variety of games over AppleTalk and TCP/IP networks.
-
- There is also a Macintosh version of ping, called Mping; it is
- available from ftp.apple.com as one of the examples of a TCP/IP
- application (file /dts/mac/netcomm/mactcp-1-1-examples.hqx).
-
- A bare-bones prototype of an SNMP management console can also be found
- on ftp.apple.com, in the file /pub/apple-ip/snmptool1.0d7.sit.hqx. It is
- rather crude, but I did use it to snatch some useful data from our
- network devices.
-
-
- Please let me know what are your favorites in this category - I'll
- be happy to expand this section!
-
-
- IV. Sources
-
- 1. Downloading text files
-
- Use any account available to you on a well-connected host. Type
- "ftp sumex-aim.stanford.edu" (or if that doesn't work, try "ftp
- 36.44.0.6"). Type "anonymous" as login name, and your mail address
- as password. In 9 cases out of 10, archives such as this one
- accept "ftp" in place of "anonymous", which means that you can
- delay the onset of carpal tunnel syndrome. You will also discover
- that many sites will accept any password at all, but let's be nice
- to those folks who specifically ask for the real id.
-
- Enter "cd /info-mac/report", and then "get ftp-primer.txt". When
- you see "Transfer complete", type "quit" and read the file you
- just downloaded.
-
- After becoming skilled in using ftp, download some more text files
- from the /info-mac directory:
-
- help/accessing-files.txt
- report/how-do-i-find.txt
- report/internet-access-11.hqx
- report/ftp-sites.txt
-
- A Macintosh communications FAQ ("frequently asked questions") list
- is an invaluable source of information. It is posted periodically
- in the Usenet newsgroup comp.sys.mac.comm; it is also available
- for anonymous ftp on rascal.ics.utexas.edu as communications.FAQ
- in the directory mac/faq.
-
- The anonymous ftp site nnsc.nsf.net run by the National Science
- Foundation is a good source of background information about the
- Internet (see directories /nsfnet and /info).
-
-
- 2. What next?
-
- When you have learned how to download Macintosh executable files,
- it's time to go hunting for specific applications.
-
-
- WARNING!!!
- The minute you start downloading files from the network, you
- become more susceptible to viral infection than before. I strongly
- suggest that you should first get and set up the wonderful free
- virus checker, Disinfectant. Its home is ftp.nwu.edu, in directory
- /pub/disinfectant; it can also be found in many other places, e.g.
- on sumex-aim.stanford edu in the directory /info-mac/virus. You
- may then want to send its author, John Norstad, a nice thank-you
- note: we all owe him a great deal! If you have access to Usenet
- news, make it a habit to monitor the comp.sys.mac.announce group:
- it is probably the most reliable source of inform ation about newly
- discovered viruses.
-
-
- Here is a list of TCP/IP-related applications (most of which were
- mentioned above) which can be found on sumex in the directory
- /info-mac. There are many servers which maintain copies of /info-
- mac contents, such as wuarchive.wustl.edu in /mirrors/info-mac.
- Version numbers are current as of this writing.
-
- comm/archie-client-09.hqx
- comm/calypso-tool-10f1c2.hqx
- comm/chat-11.hqx
- comm/fern-mail-11.hqx
- comm/fetch-21.hqx
- comm/finger-135.hqx
- comm/ftpd-201.hqx
- comm/gopher-app-13b52.hqx
- comm/hyperftp-13.hqx
- comm/ircle-10.hqx
- comm/lee-mail-124.hqx
- comm/mac-ppp-10.hqx
- comm/ncsa-telnet-25.hqx
- comm/news-watcher-13d6.hqx
- comm/nuntius-111d17.hqx
- comm/query-it-11.hqx
- comm/talk-106.hqx
- comm/the-news-222.hqx
- comm/turbo-gopher-105.hqx
- comm/xferit-14.hqx
- cp/network-time-111.hqx
- game/game-master.hqx
-
-
- Software found on ftp servers other than sumex:
-
- ClientDA: ssyx.ucsc.edu (supersrv is there as well)
- Eudora: ftp.cso.uiuc.edu in /pub/mac/eudora
- (also on ftp.qualcomm.com)
- GopherApp: ftp.bio.indiana.edu in /util/gopher
- MacDump: bbn.com
- MacPost: pollux.lu.se in /pub/mac/comm
- MacTCP+ patch: ftp.apple.com in /dts/mac/netcomm
- MacTCP T/R ext.: ftp.apple.com in /dts/mac/netcomm
- MPing: as above, file name mactcp-1-1-examples.hqx
- NCSA/BYU Telnet: bert.cs.byu.edu
- NetNews: ftp.bio.indiana.edu in /util/mac
- POPmail: boombox.micro.umn.edu, in /pub/POPmail
- popper: lilac.berkeley.edu
- SU-Mac/IP: send e-mail to macip@jessica.stanford.edu
- TechInfo: net-dist.mit.edu in /pub/TechInfo
- TechMail: net-dist.mit.edu in /pub/TechMail
- tn3270: brownvm.brown.edu
- TurboGopher: boombox.micro.umn.edu in /pub/gopher
- WAIStation: think.com in /wais
-
- Note that Apple likes to distribute some of its software as "disk
- image" files. Such files have to be loaded into an application
- called DiskCopy (available on ftp.apple.com in /dts/utils), which
- can then produce exact copies of an original master floppy disk.
-
- A list of anonymous FTP sites (not only Macintosh-related) is
- maintained on pilot.njin.net. Many Unix hosts (and an increasing
- number of other machines) will also let you search an archie
- database of anonymous ftp sites.
-
- This should keep you busy for now...
-
-
- 3. Contacts for commercial products
-
- Please remember that I do not in any way endorse commercial
- products by listing the vendors here, and I'm not in any way
- associated with them. This is simply for your convenience. Phone
- numbers are followed by an anonymous ftp server which can be used
- to get free upgrades and information, or an e-mail address.
-
- Cayman Systems (800) 473 4776 ftp.cayman.com
- Compatible Systems (800) 356 0283 csn.org, in /compatible
- Farallon Computing (800) 344 7489 farallon.com
- Intercon Systems (703) 709 9890 sales@intercon.com
- Shiva (800) 458 3550 shiva.com
- Synergy Software (215) 779 0522 D2296@AppleLink.Apple.COM
- Webster Computer Corp +61 3 764 1100 (Australia)
- USA: (408) 954-8054 wcc@cup.portal.com
-
-
- 4. Let's end with a short sermon...
-
- Many of the applications mentioned above are NOT in public domain.
- They are either shareware, or there are restrictions on their use
- and/or distribution. PLEASE PAY FOR SHAREWARE YOU KEEP!!! Author's
- address can almost always be found by pulling down the Apple menu
- and selecting "About..." Let's keep this wonderful, affordable
- software alive!
-
-
- Appendix A. Peculiarities of Mac file transfers
-
- Macintosh files differ from files on most other machines in that
- they consist of two parts. One contains data (text, executable
- program), and the other - resources (icons, the file's creator
- code, etc.) I'm simplifying a little, but never mind. This
- complicated structure prevents us from sharing such files directly
- over the network.
-
- Moreover, there is only one language which practically all
- computers understand: the ASCII code (plain text). Even though
- this isn't a terribly elegant solution, we simply bring everything
- to this lowest common denominator to assure compatibility. For
- example, in order to send a file to someone by the current e-mail
- systems, it has to be somehow encoded into an ASCII file.
-
- The Mac community has pretty much agreed on a common standard for
- doing just that: BinHex. BinHex swallows a Mac file, icons, file
- creators and all, and converts all that into a plain text file
- filled with something that looks like garbage; it also performs
- the reverse procedure. So you need BinHex.
-
- There is one obvious difficulty, however: how do you get a BinHex
- decoder (a Macintosh application!), when you don't have BinHex?
- You will also need software which will somehow let your Mac do
- FTP. The easiest way to "bootstrap" yourself is to simply get a
- copy of such a beast from a local Mac guru or a Mac User Group. If
- you're lucky, you will lay your hands on a utility which can not
- only transfer files, but also un-BinHex them -- such as XferIt,
- Fetch, or one of the Gopher clients. You can then tell it to
- connect directly to, say, sumex, dowload the interesting BinHex'ed
- files, and decode them while they arrive. Similarly, newer Gopher
- clients such as the GopherApp and TurboGopher can download and
- decode BinHex'ed files.
-
- Another way is to get NCSA Telnet, log on to a friendly Internet
- machine, download the applications you need to that computer in
- *binary* form (e.g. the file binhex4.bin available on sumex in
- /info-mac/util) using the binary mode in ftp. Then connect back to
- your Mac using the Telnet FTP server and put the files on the Mac
- using the MacBinary mode... It sounds (and is) a bit complicated,
- but remember - this convoluted process is necessary only in the
- very beginning.
-
- Once again, we have just licked the surface of this topic here.
- For more information, see the file /info-mac/report/ftp-primer.txt
- on sumex-aim.stanford.edu.
-
-
- Appendix B. Mac networking: mini-tour
-
- In the networking world, it is easy to drown in the alphabet soup
- and the sea of obscure terms. But understanding the process by
- which computers communicate helps troubleshoot problems. We will
- go through some elementary information in this appendix. Things
- may get a bit confusing, and you may want to read what follows two
- or three times until it makes sense...
-
- For two digital devices to talk to each other, there must be a
- physical connection between them (a wire, optical fiber, radio
- link, etc.) and an agreement as to the logical organization of the
- information. In computerese, such mutual understanding is usually
- called a "communications protocol".
-
- Apple's Macintoshes use a "native" set of protocols, collectively
- known as AppleTalk. The physical aspect of AppleTalk is, very
- simply, the kind of wires the device uses. If you stick a little
- round connector into the printer port of your Mac, or in the jack
- in your LaserWriter, you are using AppleTalk over Apple's original
- slow wiring, i.e. LocalTalk. Almost nobody uses that now -- even
- Apple's own network uses Farallon's Phonenet system, but that is a
- technical detail. You are on LocalTalk.
-
- If your Mac has an Ethernet card or external adapter attached, you
- will be using AppleTalk on a physical Ethernet network; that is
- called EtherTalk. Similarly, if you install a Token Ring adapter,
- the incarnation of the AppleTalk protocol you are dealing with is
- called TokenTalk.
-
-
- The logical layer of AppleTalk handles details such as how two
- Macs can discover each other on the network, how individual nodes
- are uniquely identified, what should a Mac say to a printer or an
- AppleShare file server when it wants to use it, and so on. The
- devices you see in the Chooser (LaserWriters, file servers, or
- routers such as Netway or SNA/ps) are all AppleTalk devices. The
- beauty of AppleTalk is that you don't really care what physical
- method you use. You may see a printer on LocalTalk, or a
- LaserWriter IIg on Ethernet, or a Netway box on Token Ring -- it
- doesn't matter.
-
- But the nitty-gritty of how the actual network operates does vary
- from one kind of wire to another. The computer has to behave
- differently on each kind of network, but of course you don't want
- to know about that! Enter "network drivers": low-level pieces of
- system software which take care of that. When you put in an
- Ethernet card, you need to install the EtherTalk drivers in your
- system. Same with TokenTalk drivers. It's like speaking with
- someone over the phone, or on a walkie-talkie. The principle is
- different, but the message is the same.
-
-
- There are more and more ways of making non-Apple devices speak
- AppleTalk: that's why there are MS DOS computers on LocalTalk
- networks, Novell AppleShare servers, and you can configure your
- Sun Sparcstation to print on an Apple LaserWriter. The Internet
- world, however, doesn't know the first thing about AppleTalk. It
- only understands the collection of protocols known as TCP/IP. What
- does TCP/IP have to do with AppleTalk? The answer is "not much",
- and "nothing" most of the time. Putting a Mac on a TCP/IP network
- is like dumping an Englishman in the center of Beijing: there is a
- language barrier.
-
-
- MacTCP, the gadget we are discussing in this guide, allows Mac
- applications to use network interfaces -- such as the built-in
- LocalTalk port or an Ethernet card -- to transmit and receive data
- packets which contain TCP/IP information, and hence to communicate
- with the millions of other TCP/IP computers on this planet.
-
- Just like Apple came up with specifications for sending the high-
- level (AppleTalk) data using the various low-level, network-
- specific "transport protocols" (Ethernet, Token Ring etc.), the
- Internet has standards for sending the high-level TCP/IP data
- using the low-level network mechanisms. Ethernet is the best
- choice, since the Internet protocols were "born" on Ethernet, so
- those standards are well-established.
-
- Apple adopted a certain way of sending TCP/IP data wrapped inside
- LocalTalk packets, and MacTCP knows how to handle this. It puts
- ("encapsulates") TCP/IP information into a normal LocalTalk
- packet, and sends it out. That packet makes absolutely no sense to
- any AppleTalk device (it looks like it has garbage inside), except
- those which use MacTCP to do the reverse decoding.
-
- A standard for transmitting TCP/IP data in Token Ring packets has
- also existed for quite some time. But MacTCP did not know about
- it, until Apple released an add-on "MacTCP Token Ring Extension",
- which -- again -- takes a TCP/IP packet and beats it into shape
- before sending it through a Token Ring card.
-
-
- To make things more interesting, MacTCP used on Ethernet (or Token
- Ring) is capable of two different behaviors: it can take the
- TCP/IP data and spit it out unadorned, according to the usual,
- world-savvy IP-on-Ethernet or IP-on-Token Ring recipe. But it can
- also be set to use EtherTalk (respectively, TokenTalk), which
- means that it will activate the wrapping/unwrapping AppleTalk
- filter between the network interface and the application software!
- The general idea is *not* to use EtherTalk or TokenTalk in MacTCP.
- The reason should become clear soon.
-
-
- To summarize, here are some scenarios. (a) Mac on Ethernet, MacTCP
- correctly installed, "Ethernet built-in" set in the MacTCP control
- panel; (b) Mac on Token Ring, MacTCP installed, the Token Ring
- driver installed and configured properly, TokenRing selected in
- MacTCP. All is peachy. A TCP/IP-aware application on the Mac (such
- as NCSA Telnet, etc. -- see Chapter III) wants to communicate with
- a Cray at the Space Station "Freedom", which by the time I finish
- this will be in orbit. It tells MacTCP to send out a Telnet
- packet, MacTCP translates it into the standard format for Ethernet
- or Token Ring, some gateways down the road convert it to the
- TCP/IP over radio waves form, the packets gets to the Cray, it
- says "Aha! we've got a hacker trying to log in here", and so it
- goes.
-
- Now for something more mundane. (c) Mac Plus on LocalTalk, MacTCP
- installed, "LocalTalk built-in" selected in the MacTCP panel (the
- only possible choice!). A TCP/IP "datagram" goes out after being
- wrapped into an AppleTalk packet! Now, the LocalTalk is no doubt
- connected to the outside world one way or another. If that's done
- using a relatively unsophisticated device, it will take the data
- and simply convert it to an equivalent EtherTalk, TokenTalk, or
- whatever packet. That one goes out allright, gets up to the Cray,
- but it now says: "Phooey, that's something I don't understand! It
- has some strange stuff inside! Let's quickly drop it on the
- floor." The reason is that most Internet hosts, like our Cray, are
- not instructed by their software to go deeper inside the packet
- and actually recognize that it was TCP/IP information wrapped
- inside AppleTalk... and why should they bother? What is needed is
- a more sophisticated gateway between the LocalTalk and the outside
- network.
-
- Scenario (d): Mac Plus on LocalTalk sends a TCP/IP-in-AppleTalk
- packet which is directed towards a "DDP-IP gateway", such as the
- Fastpath, Gatorbox, EtherRoute/TCP, etc. The gateway's software is
- smart enough to look under covers and see what is hiding inside.
- If it sees TCP/IP data wrapped inside AppleTalk, it strips the
- outer layer and passes the raw IP information in the standard
- format to the Ethernet network. All is well again! LocalTalk-to-
- Ethernet gateways like that are common, but equivalent ones for
- Token Ring are still scarce and expensive.
-
- How about (e): just like in scenarios (a) or (b), except MacTCP is
- set to use EtherTalk (or TokenTalk). Now regular TCP/IP packets
- will not be coming through -- MacTCP simply ignores them! It
- expects AppleTalk packets only. It will be able to communicate
- with the Mac Plus in (c), but not much else. So let's just forget
- it and stop here...
-
-
- Appendix C. Dial-in access
-
- In our personal opinion, the most elegant way to connect a Mac to
- a TCP/IP network is AppleTalk Remote Access (ARA), a commercial
- product of Apple Computer, bundled with PowerBooks, and sold as a
- separate product.
-
- ARA uses the Communications Toolbox (built into System 7, and
- installable in System 6.0.x) to ship AppleTalk packets over a
- modem to an ARA server, which is presumably connected to a "real"
- network. MacTCP in turn uses the AppleTalk protocol to transmit
- "wrapped" TCP/IP packets (if it is configured to communicate via
- AppleTalk). This results in a two-stage translation: TCP/IP-to-
- AppleTalk, and AppleTalk-to-modem. The data have to be decoded by
- a reverse process at the other end.
-
- This explains the only major drawback of ARA: speed. A 2400 baud
- modem is next to unusable in this configuration. But a 9600 baud
- connection should provide decent response even with the additional
- IP encapsulation.
-
- The server Mac, whether it's on Ethernet or LocalTalk, spews out
- AppleTalk packets, from which the TCP/IP information has to be
- reconstructed by an IP gateway. If you don't have a gateway such
- as the Fastpath, GatorBox, EtherRoute, or MultiGate, you can't use
- ARA for TCP/IP access to the network.
-
-
- Since for most of us the primary Internet application is e-mail,
- we will mention the "poor man's" dial-up connections which can be
- used with the mail client Eudora. You need to know how to edit a
- program's resources to patch Eudora in this fashion -- a task
- which is not for the faint-hearted. The two alternatives are:
-
- i) modify "stock" Eudora to navigate through a simple modem
- connection;
-
- ii) use the Simon Fraser University version of Eudora and create
- an intelligent connection script.
-
- The first method is described in the Eudora Q&A stack available
- from ftp.qualcomm.com and ftp.cso.uiuc.edu. Additional information
- is in an appendix in the Eudora documentation, available from the
- same sources. We have successfully used this scheme with a direct
- modem connection to a Unix POP server.
-
- The second way is to learn a simple C-like programming language
- which the SFU Eudora understands, and use it to get through the
- maze of terminal servers and multiple logins. This version of
- Eudora is available from fraser.sfu.ca.
-
- A much more "modular" and reliable option is to make use of a
- Communications Toolbox module which can interpret so-called CCL
- scripts. One such tool is Calypso, which acts as a buffer of sorts
- between the application itself (e.g. Eudora), and the actual
- communications tool such as the Apple Modem Tool. The progress of
- the connection is then controlled by a program (written in CCL)
- which resides in an ordinary editable text file. Learning CCL is
- not hard, given that many sample CCL scripts can be found on sumex
- and elsewhere.
-
- The most popular dial-in connection schemes, however, employ
- protocols developed specifically for that purpose, such as SLIP or
- PPP. I have seen a Communications Toolbox PPP tool, but lacking
- access to a PPP server I cannot say anything about it. SLIP was
- recently made available on the Mac in the form of several
- commercial offerings from Intercon, Synergy Software, and TriSoft.
- More information on SLIP can be found on ftp.bio.indiana.edu in
- the directory /util/slip.
-
- A suitably configured SLIP connection gives the dial-in Macintosh
- all the functionality of a node attached directly to a TCP/IP
- network, even though it is of course usually much slower. For
- example, Alan Piszcz (alan@kaman.com) described his 9600 baud
- dial-in setup as follows:
-
- REMOTE SITE OFFICE
- -------------------------------- ------------------------------
- MAC II--MacTCP--MacSLIP--Telebit===Telebit--PC NFS--UNIX--SUN SPARC
- Sys. 7 1.1 1.0 T2500 T2500 SLIP 4.0 TCP/IP 4.1.1
-
-
- Last but definitely not least -- Patrick Hoepfner kindly allowed
- me to include his introduction to the serial Internet protocols.
- Here goes:
-
-
- SLIP or Serial Line Internet Protocol is a method of pushing IP
- packets down a asynchronous (usually phone) line. SLIP is a self
- described "non-standard" that was developed on the back of an envelope
- and implemented in 1/2 a day. SLIP simply sticks a single character in
- front of the IP packet. Because you have binary IP packets over this
- connection, this has to be an 8-bit clean connection. You have to have
- both modems using 8-bit, no parity, and no software flow control.
- Because of this, many may not want to invest in software to do this if
- your organization doesn't have modems that will support this.
-
- SLIP requires that the Mac SLIP its IP packets. VersaTerm, MacSLIP,
- and InterCon supply SLIP software. The only difference (other than
- cost) is that VersaTerm SLIP and MacSLIP will work with any MacTCP
- software. InterCon uses its own proprietary TCP/IP driver and
- consequently it will SLIP only its own tools that use its TCP/IP
- drivers. But then again, InterCon can supply most all of the tools that
- you need. Since all of the SLIP products for the Mac are commercial
- products, you should refer to their documentation for information on
- setting it up on your Mac.
-
- For a successful SLIP connection you have to have a machine that will
- host the SLIP connection. That can be a unix machine, a VMS machine, or
- even a terminal server. There are public domain versions of SLIP for
- unix machines that are available, check your local archie server for
- more information. If you have a Vax running VMS and you have a TCP/IP
- package installed on it, chances are good that it too will host a SLIP
- connection. (See your local system administrator for more information.)
- And if you have a terminal server, chances are good that it too will
- support a SLIP connection (but not a CSLIP connection--see below for
- CSLIP information and see the terminal server's administrator for more
- details.)
-
- CSLIP or Compressed SLIP compresses the TCP/IP headers that are sent
- with each packet. The header are much the same each time and when using
- CSLIP, each machine keeps a copy of the last header and only transmits
- the differences between the last one and the current one. This can make
- the difference between a 4-5 byte header and the standard 40 byte
- header.
-
- PPP or Point to Point Protocol is kind of like SLIP done right.
- Among other wondrous things that PPP can do is to send not just IP
- packets, but it is able to accept other types of protocols... Maybe we
- will see AppleTalk over PPP. Maybe with the next release of AppleTalk
- Remote Access and MacTCP??? Maybe the version after that...
-
- How come I know so much about SLIP, CSLIP, and PPP? Other that
- being a genius and terribly handsome (and somethimes able to
- spell). I was pointed to two documents at "ftp.uu.net" in the
- "vendor/MorningStar/papers" directory. These unix compressed
- PostScript files are named "sug91-cheapIP.ps.Z" and "ppp-white-
- paper.ps.Z".
-
-
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