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%% Floppy Disk Port Based Amiga Network       by Douglas J. Nakakihara %%
%%                                                 dnakakihara@bix.com %%
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/********************************************************************
NOTICE: This is the originally submitted text for an article that
appeared in the March 21, 1994 issue (#121) of MICROTIMES magazine. 
(There are some slight edited differences between the published
version and this one.)

This article is freely-distributable as long as it remains unchanged
and this notice and the copyright remain included.

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without obtaining prior approval from the author.  This provision
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Specific permission has been granted to Amiga Report.

Copyright(C)1994 Douglas J. Nakakihara.

The author can be reached thru Internet at dnakakihara@bix.com.

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Floppy Disk Port Based Amiga Network
By Douglas J. Nakakihara

   Spectronics International U.S.A. is now shipping a terrific 
product called AmigaLink that allows Amigas to be networked using the 
floppy drive port! Now even slotless models like the A500, A1200, and 
CDTV can be part of a network. 

   Although networking usually involves multiple users, single users 
can also benefit. Each step in the evolution of the Amiga has meant some 
incompatibility or another. As a result, many Amiga owners continue to 
hang on to them, even after purchasing a newer model. By networking 
them, peripherals can be shared, allowing maximum use of all hardware. 

ParNet 

   Of course, many Amiga owners already rely on the freely-
distributable ParNet software to network Amigas. Like ParNet, AmigaLink 
is also a so-called peer-to-peer network because all of the nodes (i.e., 
networked computers) are equals, and any one of them can access 
another's storage devices. A4000-Toaster owners will appreciate the fact 
that AmigaLink also doesn't use an expansion slot. 

   However, as wonderful as ParNet is, it's just a toy compared to 
AmigaLink. A downside of using ParNet is that only two Amigas can be 
networked, AmigaLink can have up to 20. Furthermore, because ParNet 
monopolizes the parallel port, it can be a real pain using other 
peripherals that use this port, like a printer, scanner, or audio 
digitizer. ParNet also provides no access-security between nodes. 

   Although, 20 is the recommended maximum number of nodes, that 
number can be exceeded, as can the recommended cable length limit of 330 
feet. Apparently, the amount of interference at the network's location 
determines the actual maximums. But this can only be determined by trial 
and error. For example, using shorter cabling between nodes, may allow 
you to exceed 20 Amigas. 

Installation 

   Although the manual provides adequate step-by-step instructions, 
they are spread over several chapters and the process takes longer than 
it should. Because installation is fairly involved, it would have been 
much better if the installation steps were consolidated and preceded by 
a brief overview of the procedures. In spite of this, I had two nodes up 
and running in about one-half hour. 

Hardware Hookup 

   To install AmigaLink, you must first physically connect the 
computers. The petite AmigaLink adapter is basically a 23-pin connector 
with a BNC T-connector protruding from where a cable would normally 
exists. A removable terminating cap is attached to one end of the T-
connector. AmigaLink will work with pass-through connectors and you can 
still have up to three floppy drives on each Amiga. 

   Each Amiga must have its own adapter and 50-ohm RG-58 coaxial 
cabling is supplied to connect the them together. By removing the 
terminating cap, you can daisy-chain multiple computers together; 
however, there must be a terminating cap on the first and last nodes. 
The procedure is easy and you don't even have to open a computer case! 

   The T-connector portion of the adapter is removable and you can 
disconnect or reconnect nodes without powering down. Connections will be 
re-established once nodes are reattached. However, you should never add 
or remove an AmigaLink adapter while the computer is running. 

Software Installation 

   The software is installed in three steps. First you must install 
the device driver on each Amiga. This is accomplished by merely clicking 
an icon and following the instructions. The manual provides detailed 
instructions on what AmigaDOS commands must be available for the 
installation script to work properly (e.g., Run, NewCLI, Copy, etc.). If 
the software is being installed on a floppy disk, you must delete some 
files to make room for the AmigaLink software. A handy list of deletable 
files is provided for Workbench 1.3 and 3.0 disks. Between the two, you 
can come up with a list for a 2.x Workbench disk. Obviously, you should 
use a copy of your original Workbench disk. 

   The second step is to install the file system software on each 
computer. Again, this is a click-and-go procedure. During this process 
you will be asked for a "host" name. Each node must have a unique name, 
like "Dougs4K", or "CDTV1." I'd recommend that you keep names as short 
as possible for reasons you'll see later on. (I was surprised to find 
that the AmigaLink device driver is SANA-II compatible (Standard Amiga 
Network Architecture). This means that ENVOY or other SANA-II compatible 
networking software can be used instead of the AmigaLink file system 
software.) 

Configuring Nodes 

   Once the device driver and file system are installed on all 
Amigas, the third step is to run the configuration programs on each 
node. These programs do not have to be installed on each node and can be 
run from the AmigaLink floppy disk. However, I found it more convenient 
to copy them to my hard drives for possible future configuration 
changes. There are two configuration programs: Import and Export. 

Export 

   Export allows you to identify which devices are available to other 
nodes. Remember, AmigaLink is a true multi-user network. As such, you 
can keep certain devices private and not allow remote access. This 
covers all storage devices including RAM: and removable media, like 
floppy drives (a disk must be present).  

   The Export settings can be saved as a default or just used for the 
current session. The settings file is saved in the ENVARC: directory 
under Networks. (ENVARC: is a standardized storage area for 
configuration information.) You can also save multiple settings. 

Import 

   Running the Import program brings up a list of the other nodes on 
the network, called "hosts." By selecting one of the hosts with the 
mouse, a list of all of its available (i.e., exported) devices appears. 
You can then select which devices should be mounted on this particular 
node. (Normally, the Export program should be run on all nodes before 
running the Import program.) 

   To avoid name conflicts, Import automatically appends the name of 
the Host to the front of the device and volume names. (Remember, every 
Amiga storage device has both a device and volume name, which are 
usually different.) For example, the device and volume names "HD1" and 
"Work" on host "A3000" become "A3000-HD1" and "A3000-Work", 
respectively. So if a node already had a HD1 device called Work, a 
similarly named device on a remote node could be accessed without 
conflict. The default names can be changed, however. 

   The Import settings are saved in a file in the WBStartup drawer. 
Although this is a logical location, booting up without all nodes active 
will yield a slew of annoying error requestors. You can drag the Import 
icon out of the WBStartup drawer, but you'll have to move it every time 
new settings are saved. I remedied this by adding some lines to my 
Startup-Sequence that checks for the Import files in the WBStartup 
drawer and then moves them to another drawer. This works because the 
Startup-Sequence is executed before WBStartup programs are run. I don't 
know why the Import settings aren't saved in the ENVARC: directory just 
like the Export settings. This would allow the Import startup icon to be 
placed anywhere. 

Utilities 

   Diagnostic utility programs are also supplied. One is a self-
testing program which identifies hardware problems. Two other programs 
test the receiving and sending abilities of computers on the network. 
The Statistics program monitors and displays network performance 
information. 

Network Printing 

   AmigaLink comes with a utility program called Spooler, which 
allows multiple nodes to "print" to the same printer. Spooler is run on 
the node with the printer, referred to as a "print-server." The program 
monitors a user-specified directory for activity. When a file is 
completely "printed" to that directory, Spooler sends it to the printer 
port, usually PAR:, and then deletes the file. 

   All other nodes must run the AmigaDOS CMD command, usually found 
in the Tools or Utilities drawer. Generally, CMD is used to redirect 
printer output to a file in RAM:. However, the output it intercepts can 
also be redirected over the network to the monitored Spooler directory. 
You should be able to set up multiple print-servers, each running its 
own Spooler. Nodes could then print to any of these servers by simply 
changing the CMD redirection. 

   Do not run CMD on the print-server, however. Doing so will create 
an endless loop: CMD redirects data headed for the parallel port to the 
Spooler directory, Spooler then sends this back out to the parallel 
port--you get the idea. 

OS1.3 

   Although, AmigaLink was developed for OS2.0+ users, it functions 
fine using OS1.3 (reportedly even on an Amiga 1000). It's not as 
automated as under OS2.0+, so you'll have to use some CLI commands. 
However, you can modify your Startup-Sequence to automate the process. 
Remember to include the StartServer command, as the installation process 
does not do it for you. 

My Network 

   My test network consisted of an Amiga 3000, 4000, and CDTV. The 
CDTV required using a pass-through external floppy drive. Since many 
external floppy drives, like the "official" black CDTV ones, do not have 
a pass-through connector, Spectronics will be releasing an inexpensive 
T-connector providing pass-through capabilities. An adapter for CD32 is 
supposedly in the works too. (Note: If you don't have a keyboard for 
your CDTV, there are a few public domain utility programs that emulate 
keyboard input using a mouse.) 

   I was extremely impressed with the AmigaLink. The network is 
professional and well implemented. Remote devices function just like 
local ones and their icons appear right on the Workbench, including 
"left out" icons (OS2.0+)! The network is virtually invisible. Here is 
where my earlier suggestion for short Host names comes into play. Volume 
names that display wider than their icon, will make for a real ugly 
Workbench! This is not a functional problem, but could become 
aesthetically annoying. 

   To network a CDTV, you'll need to have a non-booting CD inserted 
into the unit so it will boot off the floppy drive. I was happy to find 
that AmigaLink handled changing the CDs. Although the volume name didn't 
change, I could still access it. To get the name to change you must 
unmount and remount the device.  

   When I rebooted a node, I found that on remote nodes, I had to 
unmount and then remount any devices imported from the rebooted node. 
This was so, even though the Import program indicated the devices were 
mounted. You can click the "mounted" button twice or do it from the CLI. 
When there are a lot of devices, a script file to unmount devices works 
great. 

   I also found a conflict between by Goldengate 486 board and 
AmigaLink. However, as long as I didn't try to access a device on the 
Amiga with the GG486 while it was emulating, all was fine.  

Performance 

   Since Amiga floppy drives are no speed-burners, I was very 
interested to see what kind of performance a floppy port network could 
achieve. The manual states that the data transfer rate is 450,000 bits-
per-second, which translates to about 55 kilobytes-per-second (kbps). My 
best case was a disappointing 40kbps on my network, while ParNet 
achieved around 61kbps. 

   However, this is only half of the story. During transfers, ParNet 
hogged CPU time, while AmigaLink barely required any. So although 
AmigaLink is slower than ParNet, it uses substantially less system 
resources, which could be a factor when multitasking. Still, AmigaLink 
is just fast enough not to cause an anxiety attack. 

VideoToaster Farm 

   Spectronics is also considering releasing software to do 
simultaneous Lightwave rendering on multiple Amiga/Toaster systems. This 
is an excellent application for AmigaLink because a fast transfer rate 
is not a requirement. "Rendering farms"--just like the big boys (i.e., 
Amblin Imaging (seaQuest DSV) and Foundation Imaging (Babylon 5))--are 
now within the reach of smaller 3D studios. 

Worth The Price 

   This is an extremely important product for the Amiga and one that
I am very excited about. At $260 for a two-node network, AmigaLink may
seem a little expensive, but a functionally equivalent Ethernet-based
network would cost you many times that. AmigaLink performs like a full-
fledged network--albeit a little slower--and is well worth its cost.

AmigaLink, $259.95 for two computers
$124.95 for each additional
Spectronics International U.S.A., Inc.
34 East Main St. #3 
Champaign, IL 61820 
(217)352-0061