Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!husc6!rutgers!labrea!decwrl!pyramid!prls!philabs!sbcs!root From: root@sbcs (Root) Newsgroups: comp.sys.amiga Subject: Re: The Next Generation (long) Message-ID: <840@sbcs.sunysb.edu> Date: Thu, 26-Nov-87 11:28:42 EST Article-I.D.: sbcs.840 Posted: Thu Nov 26 11:28:42 1987 Date-Received: Mon, 30-Nov-87 00:49:57 EST References: <2946@batcomputer.tn.cornell.edu> <2846@cbmvax.UUCP> Organization: State University of New York at Stony Brook Lines: 193 Summary: real cheap networks In article <2846@cbmvax.UUCP>, daveh@cbmvax.UUCP (Dave Haynie) writes: > in article <2946@batcomputer.tn.cornell.edu>, hsgj@batcomputer.tn.cornell.edu (Dan Green) says: > > Summary: We want info on a cheap LAN, or in fact any LAN for amigas. > > Thanks in advance for any information. > > You already know about the AmeriStar Ethernet/Arcnet stuff, which certainly > qualifies as a LAN, though not CHEAP, for the Amiga. This does do Amiga-to- > Amiga as well as Amiga-to-Sun, so it does what you want, only not as cheaply. > If you look at the prices for IBM Ethernet cards with companion software, I think you'll find that the Ameristar Ethernet product is cost competitive. The example I like to use is Sun's PC-NFS product: it's about $900 or so with Ethernet controller card. > I know of at least two third party groups working on LANs that would definitely > fit the cheap category, and of at least two more that sound like they are Let's consider the usual alternatives for "low cost" networks - at least the ones I've seen: o Serial port networking: usually limited to a two node network due to the limitations of RS-232. Can be expanded by going RS-422 or by using a multi-port serial board as a hub. Physical layer costs -------------------- Serial port, 2 nodes: $15 for a cable Serial port, 8 nodes: ~$500 (8 port hub) + $15/node (cable) Appletalk: ~$174 (board) + ~$20/node (cabling) Comments: --------- I've seen at least one IBM PC product that manages ~113 kBits/sec by hanging the machine in a polling loop catching the bytes as they come off the port - with multitasking on the Amiga, this is not an an option. From the experiments I've run on the machine, you would probably be hard pressed to get beyond ~25kbits/sec using the standard Amiga serial hardware. You'll probably find that transparent file services at 25 kBits/sec are very unacceptable. The answer to both speed and device count problems is to go Appletalk, but this requires some (limited) hardware. Eventually, you'll find out what the Mac people already know - Appletalk's ~200 kBit/sec speed just doesn't satisfy the needs of classroom size installations that use file servers. o Parallel port networking: I've heard (over the years) of a couple groups working on parallel port based networks. All the the efforts are pretty limited in scale (distance & device count), due to cable & signal level problems. I few weeks back, Matt Dillon (sp?) at Berkeley claimed to be working on a 2 node network of this type. Cost: ~$25 for a cable between 2 nodes. Comments -------- For small networks, parallel ports are probably the way to go, as you have enough handshaking to do flow control. Haven't looked at the Amiga parallel port hardware to see whether it can be scaled beyond 2 nodes (ie if the ports are open drain, they probably can be scaled) network. Of course, inter node distance would be a killer since shielded multiconductor cable is very expensive. o SCSI port networks: requires hardware, is distance & number of devices limited. Expensive cabling (especially if you're a real company and have to worry about passing FCC). Cost: ~$100 (how much is CLtd's board??) + $45 (cable, per node) Comments -------- Same as parallel port network, but with guaranteed expandability to at least 7 other nodes. Same (or worse) problem with cabling. o Arcnet network: requires hardware, is limited to ~20 nodes for certain types of transceivers. Cost: ~$400 + ~$15 (cable + "T") Comments -------- Arcnet is very much like a *fast* serial port network - each byte is sent as 11 bits; the extra 3 bits are framing, like you see in RS-232 communications. Max bandwidth (theoretical) is therefore 8/11 * 2.5 mBits/sec. Arcnet is nice because of the variety of transceiver types - cheap transceivers do 4 nodes using a resistor hub, the ones we use allow a bus architecture of 20 nodes, and there are fiber optic transceivers and hubs available for noisy environments. Arcnet is popular in Europe. o Ethernet network: requires hardware, is limited to ~30 nodes (cheapernet) or 100 nodes/seg (Ethernet). Cost: $699 + ~$15 (cable + "T") [cheapernet] $699 + ~$60 (drop cable) + ~$200 (xcvr) [ethernet] Comments -------- The folks buying Ethernet are generally doing so because they have such networks installed in house, and need compatibility. Cost is generally not a factor, since they tend to buy more than one and get a price break on software/hardware. Of course, there are many other media options available, eg 'PC token ring, Starlan, etc, but I've kept the list to projects I've heard about. Also note that the above costs are for the physical media. The software is almost always charged "per node" and tends to run from ~$50/node to >$300/node. From the above table, the lowest cost solution for reasonably sized networks is to go with Appletalk or something very similar. I arrived at the $174 figure by considering the hardware support for Appletalk: Amiga bus I/F: $8 (pal, buffer, comp, latch) Circuit board: $20 (double sided, moderate quan) 8530 SCC: $10 422 xcvrs: $5 misc: $15 (connectors, resistors, etc) ---- $58 End cost to customer (* 3 to cover assembly, test, profit, overhead): $174 Software, per node: ~$25 ---- $199 Of course, it is possible to trim the costs back a bit if there is sufficient volume. Let's be generous and say that a card could be sold for ~$125. Now the big question is: can I make money at such a price point? Let's say there are 1 million machines out there and a whopping 1% need to be networked: .01 * 1000000 = 10000 machines to be networked. Let's be wildly optimistic and say we'll capture 1/2 the network market for the Amiga. That's now 5000 machines that I can sell to. So we have: 5000 * .70 * ($125 + $25) = $612500 (gross) ^-- dealers discount is 30 % of list.. Let's say we can do that in a year. Our hypothetical gross profit on sales of $612500 looks like this: $612500 ($20000) (office, power, electricity, maintenance, 1 year) ($10000) (telephone, 1 year) ($20000) (advertising, couple mags, 1 year) ($10000) (3 shows, 2 people, 1 year) ($5000) (support services, BBS costs, etc) ($306000) (cost to produce 5100 boards - at $40 parts cost, $10 assembly, $10 misc. The extra 100 units are your spares, show units, evaluation units, and yield) ($5000) (Misc office expenses, eg mailings, UPS, etc) ------- $236500 ($25000) (Amortized engineering costs, ie board layout, FCC testing, development hardware/software, licenses if any, personnel time, etc) ------- $211500 ($9000) (secretary, 1 year @ $4/hr) ($75000) (2 engineers @ $30K + 25% overhead) ------- $127500 (not too bad, but what are you doing next year? How much of this will be committed to capital equipment, R&D, support salaries, etc). The above figures vary quite a bit depending on the organization, locale, etc. They also neglect some important areas, eg interest expense. Anyways, you can begin to see why any low volume products cost a lot of money - and, let me tell you from experience, the market for networking products isn't close to 10000 (or even 5000) units per year. The long term solution to low cost networking is to get Commodore to include something like Appletalk or Arcnet as a motherboard option on the next machine. With the media problem out of the way, software will pretty much take care of itself, especially if they would provide a cheap transport protocol with the OS. From my experience with the characteristics of the Amiga network product market, I doubt you'll see hw/sw package for less than ~$150 or so, especially if you want more than ~5 machines in one network. Rick Spanbauer SUNY/Stony Brook (& Ameristar)