|
Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
I'm trying to set up a 10base5 segment at home, can I use radio amateur
type rg-8 or do I have to have the yellow rg8 designed for 10base5? I have tranceivers and a piercing tap, and assume I can terminate with a resister between ground and center. I think I saw they were only terminated at ONE end, but maybe it would be better to terminate with 150 ohms at both ends? After all, 10base2 was supposed to be terminated at both ends, wasn't it (I always did)? Also, does anyody have operating 10broad36 or any of the 1 mb/sec ethernet-like protocols? |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
In article <1110193199.525710.184110@l41g2000cwc.googlegroups .com>,
sqrfolkdnc <carey.schug@gmail.com> wrote: >I'm trying to set up a 10base5 segment at home, can I use radio amateur >type rg-8 or do I have to have the yellow rg8 designed for 10base5? I >have tranceivers and a piercing tap, and assume I can terminate with a >resister between ground and center. I think I saw they were only >terminated at ONE end, but maybe it would be better to terminate with >150 ohms at both ends? After all, 10base2 was supposed to be >terminated at both ends, wasn't it (I always did)? > >Also, does anyody have operating 10broad36 or any of the 1 mb/sec >ethernet-like protocols? > The orange cable was terminated at both ends with 50 ohm (nominal) N connector terminators. ISTR that a tap in 10base5 was capacitive. It was just a little antenna poked thru the coax shield. Google for "ethernet blue book dec intel xerox". You might interesting info. Looking for info I found this blast from the past, last updated in 1994. http://suresh_kr.tripod.com/ethernet.txt Who knows what will work with a small hobbyist network but when it was curent nobody ever used anything but the orange cable, for many reasons. For one, the tap clamps wouldn't fit right on coax unless the O.D. was correct. Nobody I know tried anything but orange cable. Putting the taps in was a big deal at first. There was a tool kit that had a battery electric drill, a jig, and the right drill bits. Later, 3rd-party taps came along that were self-tapping, they came with a hex wrench. -- a d y k e s @ p a n i x . c o m Don't blame me. I voted for Gore. |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
sqrfolkdnc wrote:
> I'm trying to set up a 10base5 segment at home, can I use radio amateur > type rg-8 or do I have to have the yellow rg8 designed for 10base5? I > have tranceivers and a piercing tap, and assume I can terminate with a > resister between ground and center. I think I saw they were only > terminated at ONE end, but maybe it would be better to terminate with > 150 ohms at both ends? 50 Ohms, not 150. And you terminate at both ends. You _ground_ at only one point. > After all, 10base2 was supposed to be > terminated at both ends, wasn't it (I always did)? > > Also, does anyody have operating 10broad36 or any of the 1 mb/sec > ethernet-like protocols? Ebay is your friend and good hunting. -- --John to email, dial "usenet" and validate (was jclarke at eye bee em dot net) |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
sqrfolkdnc wrote:
> I'm trying to set up a 10base5 segment at home, can I use radio amateur > type rg-8 or do I have to have the yellow rg8 designed for 10base5? I > have tranceivers and a piercing tap, and assume I can terminate with a > resister between ground and center. I think I saw they were only > terminated at ONE end, but maybe it would be better to terminate with > 150 ohms at both ends? After all, 10base2 was supposed to be > terminated at both ends, wasn't it (I always did)? > > Also, does anyody have operating 10broad36 or any of the 1 mb/sec > ethernet-like protocols? Why one earth would you want to take such a huge step backwards? While you could use RG-8, I believe the ethernet cable was made with specific tap points, where it was easier to connect the taps. Also, you need 50 ohm terminators at each end. Do you also have NICs that can support the transceivers? |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
In article <mMidnZ2FCM-r_LHfRVn-3Q@rogers.com>,
James Knott <james.knott@rogers.com> wrote: >sqrfolkdnc wrote: > >> I'm trying to set up a 10base5 segment at home, can I use radio amateur >> type rg-8 or do I have to have the yellow rg8 designed for 10base5? I >> have tranceivers and a piercing tap, and assume I can terminate with a >> resister between ground and center. I think I saw they were only >> terminated at ONE end, but maybe it would be better to terminate with >> 150 ohms at both ends? After all, 10base2 was supposed to be >> terminated at both ends, wasn't it (I always did)? >> >> Also, does anyody have operating 10broad36 or any of the 1 mb/sec >> ethernet-like protocols? > >Why one earth would you want to take such a huge step backwards? While you >could use RG-8, I believe the ethernet cable was made with specific tap >points, where it was easier to connect the taps. Also, you need 50 ohm >terminators at each end. Do you also have NICs that can support the >transceivers? It sounds like a hobbyist network. That's cool. Redirecting the thread to alt.folklore.computers might get more info. A query there might turn up orange cable and related bits of kit. The stripes were for mandatory tap seperation. There are lots of little adapters around to convert the AUI connector on the tap to TW or UTP. Google for a copy of the DEC/Xerox/Intel "Blue Book" spec for the original ethernet. It's one of the clearer bits of technical writing you'll ever read. -- a d y k e s @ p a n i x . c o m Don't blame me. I voted for Gore. |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
In article <d0hokc0288d@news4.newsguy.com>,
J. Clarke <jclarke.usenet@snet.net.invalid> wrote: >sqrfolkdnc wrote: > >> I'm trying to set up a 10base5 segment at home, can I use radio amateur >> type rg-8 or do I have to have the yellow rg8 designed for 10base5? I >> have tranceivers and a piercing tap, and assume I can terminate with a >> resister between ground and center. I think I saw they were only >> terminated at ONE end, but maybe it would be better to terminate with >> 150 ohms at both ends? > >50 Ohms, not 150. And you terminate at both ends. You _ground_ at only one >point. > >> After all, 10base2 was supposed to be >> terminated at both ends, wasn't it (I always did)? >> >> Also, does anyody have operating 10broad36 or any of the 1 mb/sec >> ethernet-like protocols? > >Ebay is your friend and good hunting. > You've sure got a laundry list of standards there. Do you have any idea how they fit in the marketpalce in their day ? I don't know what "1 mb/sec/ ethernet-like" means. Mike Padlipsky's _The Elements of Networking Style_ has an interesting chapter on how people thought that IP (which was new and designed for point-to-point circuits) couldn't work on Ethernet, a broadcast meduim. There was _very_ little of the pre-Blue Book equipment made. It was used only at Xerox and a few universities and since the original specs allowed only a handfull of computers on a LAN there was not the tons of desktop infrastructure to be found in dumpsters. As soon as the 10mb stuff hit the market (1981 ?) people with older stuff upgraded. That was a long time ago. At this point the discussion is firmly th the alt.folklore.computers are and should be picked up there. -- a d y k e s @ p a n i x . c o m Don't blame me. I voted for Gore. |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
Al Dykes wrote:
> In article <d0hokc0288d@news4.newsguy.com>, > J. Clarke <jclarke.usenet@snet.net.invalid> wrote: >>sqrfolkdnc wrote: >> >>> I'm trying to set up a 10base5 segment at home, can I use radio amateur >>> type rg-8 or do I have to have the yellow rg8 designed for 10base5? I >>> have tranceivers and a piercing tap, and assume I can terminate with a >>> resister between ground and center. I think I saw they were only >>> terminated at ONE end, but maybe it would be better to terminate with >>> 150 ohms at both ends? >> >>50 Ohms, not 150. And you terminate at both ends. You _ground_ at only >>one point. >> >>> After all, 10base2 was supposed to be >>> terminated at both ends, wasn't it (I always did)? >>> >>> Also, does anyody have operating 10broad36 or any of the 1 mb/sec >>> ethernet-like protocols? >> >>Ebay is your friend and good hunting. >> > > You've sure got a laundry list of standards there. Do you have any > idea how they fit in the marketpalce in their day ? I don't know what > "1 mb/sec/ ethernet-like" means. He's probably talking about Starlan and its kin. Thinking about it, I _may_ actually have some 1 Mb/sec Starlan hardware in the attic. If so it will be ISA NICs--I'm pretty sure I don't have a hub. > Mike Padlipsky's _The Elements of > Networking Style_ has an interesting chapter on how people thought > that IP (which was new and designed for point-to-point circuits) > couldn't work on Ethernet, a broadcast meduim. > > There was _very_ little of the pre-Blue Book equipment made. It was > used only at Xerox and a few universities and since the original specs > allowed only a handfull of computers on a LAN there was not the tons > of desktop infrastructure to be found in dumpsters. As soon as the > 10mb stuff hit the market (1981 ?) people with older stuff upgraded. > That was a long time ago. > > At this point the discussion is firmly th the alt.folklore.computers > are and should be picked up there. > > -- --John to email, dial "usenet" and validate (was jclarke at eye bee em dot net) |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
In article <d0hlih$86n$1@panix5.panix.com>, adykes@panix.com (Al Dykes)
wrote: > > The orange cable was terminated at both ends with 50 ohm (nominal) > N connector terminators. > The orange cable was used for plenum applications; the more common cable was bright yellow. (In fact, it was "1968 Corvette Yellow," to be specific.) I have some of the original prototype batch in my garage. > ISTR that a tap in 10base5 was capacitive. It was just a little > antenna poked thru the coax shield. Google for "ethernet blue book > dec intel xerox". You might interesting info. > The tap was did not use capacitive coupling. It required that the transceiver input have DC connectivity with both the center conductor and the shield. (Remember, carrier-sense and collision-detect were based on DC voltage thresholds; a capacitive coupler would not work for this purpose.) -- Rich Seifert Networks and Communications Consulting 21885 Bear Creek Way (408) 395-5700 Los Gatos, CA 95033 (408) 228-0803 FAX Send replies to: usenet at richseifert dot com |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
In article <usenet-761616.18052507032005@news.isp.giganews.com>,
Rich Seifert <usenet@richseifert.com.invalid> wrote: >In article <d0hlih$86n$1@panix5.panix.com>, adykes@panix.com (Al Dykes) >wrote: > >> >> The orange cable was terminated at both ends with 50 ohm (nominal) >> N connector terminators. >> > >The orange cable was used for plenum applications; the more common cable >was bright yellow. (In fact, it was "1968 Corvette Yellow," to be >specific.) I have some of the original prototype batch in my garage. > >> ISTR that a tap in 10base5 was capacitive. It was just a little >> antenna poked thru the coax shield. Google for "ethernet blue book >> dec intel xerox". You might interesting info. >> > >The tap was did not use capacitive coupling. It required that the >transceiver input have DC connectivity with both the center conductor >and the shield. (Remember, carrier-sense and collision-detect were based >on DC voltage thresholds; a capacitive coupler would not work for this >purpose.) > > >-- >Rich Seifert Networks and Communications Consulting > 21885 Bear Creek Way >(408) 395-5700 Los Gatos, CA 95033 >(408) 228-0803 FAX > >Send replies to: usenet at richseifert dot com I stand corrected, thanks, but having done just a few taps myself don't see how that little pin could make a reliable connection, but It worked. -- a d y k e s @ p a n i x . c o m Don't blame me. I voted for Gore. |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
Thanks to all who replied, I will try alt.folklore.computers. This was
my first foray into groups since a brief encounter with Sun groups several years ago, and I came across the cisco group looking for something else. I have ONE N-I-B self tapping vampire tap and tranceiver. I have three tranceivers (two dual and one quad) that clearly were inteded to be spliced into RG-8 cable with coax connectors, although I have been unable to find any information on the web about these. I have 14 long and 8 short AUI cables and ISA cards/hubs/switches/routers with AUI ports to connect them to. Besides 10base2, I also have a 10baseF hub (optical fiber at 10 mb/sec) running in my lab/museum. I assume the VERY FIRST thick was traditional black RG-8, the yellow and orange came later, else why would they have used the rg-8 spec? Yes, I knew the yellow cable was marked for tap points, I thought just to enforce the separation, which I figure should not matter if I am not trying to get published maximum distance. Yes, I got confused vis-a-vis grounding at one point vs terminating at one end. The 1MB/s protocals were starlan1 and 1base5, both running on unshielded phone cable. It seems the 1 mb/s media were intended to be a local interface from desktops, implying the hubs would also have 10 mb for connedtion to the backbone, so with two hubs and a crossover, I could run it even though no current os would support any pc isa cards. 10broad36 was sharing coax with other signals (TV?) and supposed to go 3600 meters, hence the name, but some web documents said it only went 1800 meters. If anybody can help with equpment, I would appreciate it. I'd like to get a used vampire tap so I can keep the new one "new". I should be able to get started with just the RG-8 (assuming I can make my own terminators), and if I can't find yellow/orange, I'll try some local radio amateurs I know to get a little from them (On Ebay I can buy 50 or 250 feet, and just the postage would exceed my budget). |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 stillrunning?
sqrfolkdnc wrote:
> I'm trying to set up a 10base5 segment at home, can I use radio amateur > type rg-8 or do I have to have the yellow rg8 designed for 10base5? I > have tranceivers and a piercing tap, and assume I can terminate with a > resister between ground and center. I think I saw they were only > terminated at ONE end, but maybe it would be better to terminate with > 150 ohms at both ends? After all, 10base2 was supposed to be > terminated at both ends, wasn't it (I always did)? > Also, does anyody have operating 10broad36 or any of the 1 mb/sec > ethernet-like protocols? Note that 10base2 is electrically the same as 10base5, you can connect them together with BNC to N adapters. It is also easier to find BNC 50 ohm terminators, as they are commonly used in other than ethernet applications. My favorite are feed-through terminators to avoid the tee on the last connection. RG8 or RG213 will work fine. (The maximum length will be less, but I don't expect that to cause you problems.) You can solder a 50 ohm resistor at each end if you want to. N connectors are expensive, but you may be able to find them in surplus stores. -- glen |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 stillrunning?
In article <18CdnQVD--5O6bDfRVn-tg@comcast.com>,
glen herrmannsfeldt <gah@ugcs.caltech.edu> wrote: >sqrfolkdnc wrote: > >> I'm trying to set up a 10base5 segment at home, can I use radio amateur >> type rg-8 or do I have to have the yellow rg8 designed for 10base5? I >> have tranceivers and a piercing tap, and assume I can terminate with a >> resister between ground and center. I think I saw they were only >> terminated at ONE end, but maybe it would be better to terminate with >> 150 ohms at both ends? After all, 10base2 was supposed to be >> terminated at both ends, wasn't it (I always did)? > >> Also, does anyody have operating 10broad36 or any of the 1 mb/sec >> ethernet-like protocols? > > >Note that 10base2 is electrically the same as 10base5, you can >connect them together with BNC to N adapters. It is also easier >to find BNC 50 ohm terminators, as they are commonly used in other >than ethernet applications. My favorite are feed-through terminators >to avoid the tee on the last connection. > >RG8 or RG213 will work fine. (The maximum length will be less, >but I don't expect that to cause you problems.) You can solder a 50 >ohm resistor at each end if you want to. N connectors are expensive, >but you may be able to find them in surplus stores. > >-- glen > There's lots of N hardware out there, and N-BNC adapters. Ask the hams and check Fair Radio Sales. http://www.fairradio.com/ -- a d y k e s @ p a n i x . c o m Don't blame me. I voted for Gore. |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
In article <d0j1rh$3g7$1@panix5.panix.com>, adykes@panix.com (Al Dykes)
wrote: > > I stand corrected, thanks, but having done just a few taps myself > don't see how that little pin could make a reliable connection, but It > worked. Trust me, it took a *LOT* of mechanical and materials engineering to get that system to work reliably. Back in 1980-82, I was working on an almost daily basis with the folks at AMP in Harrisburg, PA who did the original 10 Mb/s vampire tap. The difficulty is in having the tap pin find its way through a viscous foam dielectric to achieve a solid berth in the center conductor of the cable. The project engineer described it as, "trying to nail Jello to a tree." His analogy was quite good. -- Rich Seifert Networks and Communications Consulting 21885 Bear Creek Way (408) 395-5700 Los Gatos, CA 95033 (408) 228-0803 FAX Send replies to: usenet at richseifert dot com |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
In article <1110256475.061246.229280@l41g2000cwc.googlegroups .com>,
"sqrfolkdnc" <carey.schug@gmail.com> wrote: > > I assume the VERY FIRST thick was traditional black RG-8, the yellow > and orange came later, else why would they have used the rg-8 spec? The very first 10 Mb/s coax medium was in fact the custom-designed yellow (and later, orange) cable; it was never RG-8, or any standard cable. The electrical and mechanical requirements of the system precluded off-the-shelf designs. (I personally designed the original yellow/orange cables; they were manufactured for me by Belden (and later, many others). > Yes, I knew the yellow cable was marked for tap points, I thought just > to enforce the separation, which I figure should not matter if I am not > trying to get published maximum distance. The separation and the maximum distance are unrelated phenomenon. The forced spacing was to prevent lumped capacitive loads on the system, which could cause unacceptable signal reflections. The maximum cable length is a function of the resistance of the center conductor, which affects the carrier-sense and collision-detect thresholds. If you have few taps (i.e., nowhere near the maximum of 100), the spacing is not that critical. > 10broad36 was sharing coax with other signals (TV?) and supposed to go > 3600 meters, hence the name, but some web documents said it only went > 1800 meters. > It all depends on how you measure it. Remember, 10BROAD36, like most CATV-style systems, uses a head-end device at the "source" of the cable. Thus, the maximum range is 1800 m (radius from the headend), or 3600 m (diameter, or maximum distance between the farthest pair of end stations); it's the same thing. > If anybody can help with equpment, I would appreciate it. I'd like to > get a used vampire tap so I can keep the new one "new". I should be > able to get started with just the RG-8 (assuming I can make my own > terminators), and if I can't find yellow/orange, I'll try some local > radio amateurs I know to get a little from them (On Ebay I can buy 50 > or 250 feet, and just the postage would exceed my budget). You may have problems trying to use RG-8 or any standard cable with a vampire tap. The dimensions/geometry are simply wrong. Also, the tap is designed to work only with a solid center conductor (not stranded) and a foam dielectric. The standard solid polyethylene dielectric of RG-8 is much too dense for the tap probe, and the higher dielectric constant reduces the diameter of the cable, i.e., the tap probe will be too long. I have a large spool of an early prototype Ethernet cable (from back in the 1980 timeframe); it is dimensionally correct, but is black instead of yellow, and has only a single braid/single foil shield (rather than the double braid/double foil of the real stuff). In fact, it was tests on this cable that brought me to add the additional shields. Unless you are local in northern California, the shipping cost would exceed its value to you. -- Rich Seifert Networks and Communications Consulting 21885 Bear Creek Way (408) 395-5700 Los Gatos, CA 95033 (408) 228-0803 FAX Send replies to: usenet at richseifert dot com |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
Rich Seifert <usenet@richseifert.com.invalid> wrote:
> Back in 1980-82, I was working on an almost daily basis with > the folks at AMP in Harrisburg, PA who did the original 10 > Mb/s vampire tap. The difficulty is in having the tap pin > find its way through a viscous foam dielectric to achieve > a solid berth in the center conductor of the cable. I'd've thought that a sprung system would be necessary. Forked vampire tip to maintain contact, maybe with some spring in the fork-tip (ala RJ solid IDC) or a slight curve in the vampire. > The project engineer described it as, "trying to nail Jello to > a tree." His analogy was quite good. Jell-O can be very easily nailed to a tree. Put it in a can. In this case, a long (6"?) circumferential compression clamp around the yellow garden hose. -- Robert |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
Any idea why it is it referred to as RG-8 all over the internet? I
wondered if thick ethernet had a special dielectic so as to be easier to cut a hole into than normal cable would be, and whether my vampire tap would be able to make it into the center conductor of normal RG-8. Where does that leave the tranceivers I have which have a pass through path for something the size of RG-8 using PL259 coax connectors, and were sold to me as thicknet tranceivers? If thicknet is larger diameter than RG-8, does that mean the PL-259 coax won't fit the thicknet? Were their special coax connectors? Or are the three tranceivers I have that have a pass through connection appearing to be for RG-8 actually a variation on thinnet? Or did later installations use REAL RG-8 and these tranceivers but not use vampire taps? The more I learn the more ignorant I become... |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
In article <1110302957.715105.211120@g14g2000cwa.googlegroups .com>,
"sqrfolkdnc" <carey.schug@gmail.com> wrote: > Any idea why it is it referred to as RG-8 all over the internet? Probably because most hams consider any (roughly) 0.4" diameter, 50 ohm cable to be "RG-8". Don't believe everything you see or read on the Internet. ;^) > I > wondered if thick ethernet had a special dielectic so as to be easier > to cut a hole into than normal cable would be, and whether my vampire > tap would be able to make it into the center conductor of normal RG-8. > We took great pains to make the dielectric soft enough to allow easy penetration, yet firm enough to prevent movement of the center conductor when the cable is bent, which would affect the characteristic impedance. The foam dielectric makes the cable somewhat thicker than RG-8. > Where does that leave the tranceivers I have which have a pass through > path for something the size of RG-8 using PL259 coax connectors, and > were sold to me as thicknet tranceivers? > One can always build a transceiver that, instead of attaching through a vampire tap, requires cutting the cable and inserting the transceiver through standard connectors. The advantage is that the complexities of the vampire tap are avoided; the disadvantage is that the network must be brought down to install each new station. > If thicknet is larger diameter than RG-8, does that mean the PL-259 > coax won't fit the thicknet? Were their special coax connectors? PL-259 (UHF) connectors were never used, at least not according to the Ethernet standard. PL-259s are not constant-impedance connectors; they are fine for non-demanding applications, e.g. ham radio. Ethernet uses Type N connectors; these are more expensive, but specified at 50 ohms impedance. They are also quite a bit more rugged. As a ham myself (KE1B), I would have liked PL-259s, since I could have gotten all I wanted as vendor samples from Ethernet cable manufacturers! Instead, I started using N connectors myself for amateur applications, and never went back. PL-259s are simply awful at GHz frequencies. > Or > are the three tranceivers I have that have a pass through connection > appearing to be for RG-8 actually a variation on thinnet? Or did later > installations use REAL RG-8 and these tranceivers but not use vampire > taps? The more I learn the more ignorant I become... No standards-compliant installation used RG-8, or PL-259 connectors. Some commercial products used Type N inline connections, but most used the vampire tap. By the way, there really is no single standard for "RG-8"; this is one of the problems we wanted to avoid. There is RG-8, RG-8/A RG-8/C, and a variety of others. Lots of manufacturers make "RG-8 style" cable; all of these vary in dimensions, attenuation, shielding effectiveness, etc. Ethernet installation would have been a nightmare if we just said "Use RG-8 cable". -- Rich Seifert Networks and Communications Consulting 21885 Bear Creek Way (408) 395-5700 Los Gatos, CA 95033 (408) 228-0803 FAX Send replies to: usenet at richseifert dot com |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
Rich Seifert wrote:
> As a ham myself (KE1B), I would have liked PL-259s, since I could have > gotten all I wanted as vendor samples from Ethernet cable manufacturers! Another one here, VE3ZU. I wonder how many people here, realize that many of the first computer hobbyists were hams? The first popular computer magazine, Byte, was originally published by Wayne Green, who also published 73 Magazine, among others, for amateur radio. There were many computer articles in 73, along with the ham radio stuff. Incidentally, I have every issue of Byte on the shelves behind me. I bought the first three issues in person, from Wayne, at the 1975 Radio Society of Ontario Convention, in Ottawa. |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
In article <GPSdnVsLU-oJrrPfRVn-2A@rogers.com>,
James Knott <james.knott@rogers.com> wrote: > > Incidentally, I have every issue of Byte on the shelves behind me. You will find an article I wrote in the January 1990 edition, chronicling the 10th anniversary of the Ethernet ("Blue Book") Specification. A group of the original designers got together in my home for a reunion party, which resulted in the article. -- Rich Seifert Networks and Communications Consulting 21885 Bear Creek Way (408) 395-5700 Los Gatos, CA 95033 (408) 228-0803 FAX Send replies to: usenet at richseifert dot com |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 stillrunning?
Rich Seifert wrote:
(snip) >>are the three tranceivers I have that have a pass through connection >>appearing to be for RG-8 actually a variation on thinnet? Or did later >>installations use REAL RG-8 and these tranceivers but not use vampire >>taps? The more I learn the more ignorant I become... > No standards-compliant installation used RG-8, or PL-259 connectors. > Some commercial products used Type N inline connections, but most used > the vampire tap. The first 10base2 installations I saw used those transceivers with N to BNC adapters on them. At one point I did use one at the end of a thick ethernet cable with type N connectors. If you want to add to your collection, I have some 100baseT4 transceivers. -- glen |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 stillrunning?
Rich Seifert wrote:
(snip) > You may have problems trying to use RG-8 or any standard cable with a > vampire tap. The dimensions/geometry are simply wrong. Also, the tap is > designed to work only with a solid center conductor (not stranded) and a > foam dielectric. The standard solid polyethylene dielectric of RG-8 is > much too dense for the tap probe, and the higher dielectric constant > reduces the diameter of the cable, i.e., the tap probe will be too long. I did it once. We bought some Suns that we were told would have built in 10base2, but didn't. We ordered some transceivers, but I wanted to get the machines running. I put two vampire taps on some RG8 (probably RG/213, actually) soldered BNC connectors onto each end, and had it running for some weeks. The only problem was that once one of the BNC connectors shorted out (they were panel mount connectors). The clamp was tight enough not to wiggle too much, but I probably wouldn't put it in the wiring tray. -- glen |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
100baseT4 "tranceivers"!! ???????
OK, the more I learn, the more I learn I don't know. I'm interested. Unless the tranceiver is 100baseTX <--> 100baseT4, in which case I am VERY interested. A web search...if I learned correctly, there is a DB40 AUI connector for 100 megabit ethernet, from which one can connect a 100baseT4 tranceiver or a 100baseF tranceiver (and maybe others), but it never caught on and interface cards nearly all have RJ45 ports for 100baseTX only. So it would be nice to have as a display item, but unless I can get network interface cards with drivers (I think I saw a reference to a list of cards supported by some linux driver including some 100baseT4 cards) and maybe a hub/switch, it is not something I could set up and have running live. As I understand it, 100baseT4 is 3 pairs transmit, 1 pair control/collision/receive I can see that meaning either a hub is a requirement or any cable can connect two DTE devices together without a hub and a crossover is not required, but I could not find anything on the web to explain how it works (probably a shortcoming in what to look for on the web, I'm sure its there somewhere) |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
Rich Seifert wrote:
>> Incidentally, I have every issue of Byte on the shelves behind me. > > You will find an article I wrote in the January 1990 edition, > chronicling the 10th anniversary of the Ethernet ("Blue Book") > Specification. A group of the original designers got together in my home > for a reunion party, which resulted in the article. Actually, it's the Jan 1991 issue, page 315. "Ethernet: Ten Years After" "Imagine a world without networks: no Novell/3Com/TOPS,..." Perhaps you could post the text or a link to it here. I'm sure others would find it interesting. |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
glen herrmannsfeldt wrote:
>> No standards-compliant installation used RG-8, or PL-259 connectors. >> Some commercial products used Type N inline connections, but most used >> the vampire tap. > > The first 10base2 installations I saw used those transceivers > with N to BNC adapters on them.***At*one*point*I*did*use*one > at the end of a thick ethernet cable with type N connectors. > The first ethernet network I worked on (or even saw), was a DECNET, connecting several VAX 11/780 computers and used vampire taps. However that's not my first experience with networks. That would be on a system built by Collins (part of Rockwell). They had a network, that instead of using packets, used time slots (time division multiplexing). When a device (computer, tape drive, disk etc.) wanted to send data, it would be assigned a time slot on the ring. The destination would then listen to that time slot. While the time slots could have been assigned dynamically, in the systems I worked on, they were permanently assigned. IIRC, the Collns 8500B had a 2 Mb/s ring over RG-58 cable, while the 8500C ran 8 Mb over triaxial cable. There were also adapters to convert between the two speeds. The ring had relay boxes, for connecting the various devices and a loop sync box, to retime the signal. As I recall, this technology was developed in the mid '60s. I was working on it in the late '70s, a few years before ethernet was created. |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
In article <vOudnfmdqNKZjLLfRVn-jg@rogers.com>,
James Knott <james.knott@rogers.com> wrote: >glen herrmannsfeldt wrote: > >>> No standards-compliant installation used RG-8, or PL-259 connectors. >>> Some commercial products used Type N inline connections, but most used >>> the vampire tap. >> >> The first 10base2 installations I saw used those transceivers >> with N to BNC adapters on them.***At*one*point*I*did*use*one >> at the end of a thick ethernet cable with type N connectors. >> > >The first ethernet network I worked on (or even saw), was a DECNET, >connecting several VAX 11/780 computers and used vampire taps. However >that's not my first experience with networks. That would be on a system >built by Collins (part of Rockwell). They had a network, that instead of >using packets, used time slots (time division multiplexing). When a device >(computer, tape drive, disk etc.) wanted to send data, it would be assigned >a time slot on the ring. The destination would then listen to that time >slot. While the time slots could have been assigned dynamically, in the >systems I worked on, they were permanently assigned. IIRC, the Collns >8500B had a 2 Mb/s ring over RG-58 cable, while the 8500C ran 8 Mb over >triaxial cable. There were also adapters to convert between the two >speeds. The ring had relay boxes, for connecting the various devices and a >loop sync box, to retime the signal. As I recall, this technology was >developed in the mid '60s. I was working on it in the late '70s, a few >years before ethernet was created. > I worked for BigBank in NYC in the late 70's and the CTO was really big on pre-standards channel-oriented broadband LAN for buildings and ISO (meaning mostly X.25) WAN. The cable plant for the BB was identical to any CATV system except we didn't have telephone poles or manholes. Our engineers joked that if/when the got downsized they could all go home and get jobs with the local cable TV company and have a shorter commute. Many of the engineering issues for our BB and an outdoor CATV system were similar because we were in a very high EMI environment (a couple thousand feet LOS from the Empire State bldg) and interference was always leaking into all sorts of stuff. Years later I could hear AM radio on my PC before streaming was invented. The CTO later went on record as "ethernat can't work" and BigBank became a huge TokenRing operation. I had to jump thru hoops to get ethernet in for my DEC datacenter. We spent MILLIONS on OSI stuff and it was a PITA to get it connected to all the types of DEC gear I had. OTOH, I had thousands of users, worldwide, by 1982. TCP/IP, What's that ? -- a d y k e s @ p a n i x . c o m Don't blame me. I voted for Gore. |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
Al Dykes wrote:
> I worked for BigBank in NYC in the late 70's and the CTO was really > big on pre-standards channel-oriented broadband LAN for buildings and > ISO (meaning mostly X.25) WAN.**The*cable*plant*for*the*BB*was > identical to any CATV system except we didn't have telephone poles or > manholes.**Our*engineers*joked*that*if/when*the*got*downsized*they > could all go home and get jobs with the local cable TV company and > have a shorter commute. > > Many of the engineering issues for our BB and an outdoor CATV system > were similar because we were in a very high EMI environment (a couple > thousand feet LOS from the Empire State bldg) and interference was > always leaking into all sorts of stuff. Years later I could hear AM > radio on my PC before streaming was invented. > > The CTO later went on record as "ethernat can't work" and BigBank > became a huge TokenRing operation. I had to jump thru hoops to get > ethernet in for my DEC datacenter.**We*spent*MILLIONS*on*OSI*stuff*and > it was a PITA to get it connected to all the types of DEC gear I had. > OTOH, I had thousands of users, worldwide, by 1982.**TCP/IP,*What's > that ? > > That Collins 8500C system that I worked on, was part of the Air Canada reservation system. That system ran on a Univac computer, and the Collins network was the communications processor for it. As I mentioned in the other note, devices such as tape drives and disks were connected to this network. There were also about 2 dozen PDP-11s connected, each with 3 or 4 serial I/O cards, each card containing a Motorola 6800 CPU and 8 UARTs, which were then connected to modems, to talk to terminals around the world. It was quite a system in it's day. |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 stillrunning?
Hello, RHS> As a ham myself (KE1B), I would have liked PL-259s, > since I could have gotten all I wanted as vendor > samples from Ethernet cable manufacturers! JAK> Another one here, VE3ZU. I'm in good company then :-) I've seen coaxial Ethernet used in places where EMC was an issue. I've thought about using it in the shack for this reason (well, that and I'm likely to have reels of it sculling about the place anyway ;-) I like BNC for low power connections, N for heftier stuff. 73, Andy, KB9YLW |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 stillrunning?
Hello, > Besides 10base2, I also have a 10baseF hub... ^^^^^^^ Which 10baseF? As I understand it there was 10baseFP (fibre passive, not widely deployed), 10baseFB (for backbone link segments, I don't know much about this) and 10baseFL, which is more common and can interwork with the earlier FOIRL standard. I've been on the lookout for a small 10baseFL hub or switch, perhaps one that supports single- mode links. - Andy Ball |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 stillrunning?
Hello Rich, RHS> The forced spacing was to prevent lumped capacitive > loads on the system, which could cause unacceptable > signal reflections. I understand that you wrote this about original 'thick' Ethernet, but I'm wondering if there are preferred lengths for 10base2 cables. Would certain lengths minimise the effect of any reflections from the BNC connectors? I don't remember 10base2 being especially fussy, but an ounce of prevention... - Andy Ball |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
Andy Ball wrote:
> I like BNC for low power connections, N for heftier stuff. > I haven't got anything that requires N connectors, but I like using BNC. If any gear comes with an SO-239 connector, I use an adapter to convert to BNC. Incidentally, one thing that really gets me, is all the names for a BNC connector. It is not "British Naval Connector" or that other common one with a couple of people's names. According to what I read in Ham Radio Magazine, several years ago, a guy from Amphenol (IIRC) said it's derived from: B - bayonet lock N - N type (you can actually plug a male BNC into a female N, though the lock won't work C - compact (version of N series) |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
James Knott wrote:
> Andy Ball wrote: > >> I like BNC for low power connections, N for heftier stuff. >> > > I haven't got anything that requires N connectors, but I like using BNC. > If any gear comes with an SO-239 connector, I use an adapter to convert to > BNC. > > Incidentally, one thing that really gets me, is all the names for a BNC > connector. It is not "British Naval Connector" or that other common one > with a couple of people's names. According to what I read in Ham Radio > Magazine, several years ago, a guy from Amphenol (IIRC) said it's derived > from: > > B - bayonet lock > N - N type (you can actually plug a male BNC into a female N, though the > lock won't work > C - compact (version of N series) Seems that Amphenol disagrees with you <http://www.amphenolrf.com/products/bnc.asp>. Unless the guy who wrote the article was named Neill or Concelman I'll take the official Amphenol story over that that appeared in a magazine. -- --John to email, dial "usenet" and validate (was jclarke at eye bee em dot net) |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
In article <L2IXd.4422$oO4.450@newsread3.news.pas.earthlink.n et>,
Andy Ball <null@not.valid> wrote: > Hello Rich, > > RHS> The forced spacing was to prevent lumped capacitive > > loads on the system, which could cause unacceptable > > signal reflections. > > I understand that you wrote this about original 'thick' > Ethernet, but I'm wondering if there are preferred lengths > for 10base2 cables. Would certain lengths minimise the > effect of any reflections from the BNC connectors? I don't > remember 10base2 being especially fussy, but an ounce of > prevention... > There was a minimum spacing requirement (transceiver-to-transceiver) of 0.5 m, but that was it. There was no preferred cable length. -- Rich Seifert Networks and Communications Consulting 21885 Bear Creek Way (408) 395-5700 Los Gatos, CA 95033 (408) 228-0803 FAX Send replies to: usenet at richseifert dot com |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
In article <lImdnZFFMrNQk7LfRVn-vQ@rogers.com>,
James Knott <james.knott@rogers.com> wrote: > Rich Seifert wrote: > > >> Incidentally, I have every issue of Byte on the shelves behind me. > > > > You will find an article I wrote in the January 1990 edition, > > chronicling the 10th anniversary of the Ethernet ("Blue Book") > > Specification. A group of the original designers got together in my home > > for a reunion party, which resulted in the article. > > Actually, it's the Jan 1991 issue, page 315. > > "Ethernet: Ten Years After" > > Perhaps you could post the text or a link to it here. I'm sure others would > find it interesting. Sure, why not? Below find the original article *as I submitted it to the magazine*; i.e., before the editor's got their hands on it. Note that even then, I was using titles and/or lyrics from popular songs for section headings, a practice I continued through my later books (a practice that the editors of BYTE Magazine disagreed with). Even the original title of the article was "Reflections of ... the Way Life Used to Be" (a line from an old Supremes song) As you read it (*IF* you read it, that is) remember that it was written in October 1990, a time when 10BASE-T was quite new, FDDI was emerging as the next-generation LAN, and Fast/Gigabit Ethernet did not yet exist. Enjoy! ----Begin Article---- Reflections of...the Way Life Used to Be One thing that differentiates humans from lower beings is their ability to defer instant gratification for long-term pleasure (some humans, anyway). One of the more difficult tasks in this regard is to hold onto a fine wine long enough to allow it to reach its peak. You see it every time you open the wine cabinet, reminding you of its wondrous pleasures to delight the palate, but still you let it lie, to reap an even greater reward later on. If you are really patient, the flavors that finally roll across your tongue are further enhanced by the remembrance of all those years of anticipation. I purchased a magnum of Cabernet Sauvignon from Heitz Cellars on September 30, 1980, the day we completed and "signed-off" the DEC-Intel-Xerox Ethernet Specification, Version 1.0. I planned to enjoy it with the Ethernet team on the tenth anniversary of that day. We recently reunited to enjoy that wine and to reflect on the evolution of LANs over the past ten years. Imagine There's no Network, I Wonder if you Can? While it's never easy to expand the horizons of one's business, at least today there is an established market for LANs. You can do the market research, listen to network users, find their needs, and determine the niches where new ideas and products can flourish. In 1980, none of this was possible. Imagine a world without networks: no Novell/3Com/TOPS, no clients, no servers. No Token Ring, Ethernet, or LocalTalk. No transceivers, wiring hubs, bridges or routers. No TCP/IP, no OSI. No PCs! Networks involved either proprietary point-to-point connections or leased lines from the telephone company, and 300 baud modems were standard. This was the environment in which the industry, and the DEC-Intel-Xerox partnership was in when we began our effort. We had to go where no LAN had gone before. A blank sheet of paper is a scary proposition. Most engineers and product marketers rarely get to work with one. You are usually designing a product which is second- or third-generation, an incremental improvement on an existing concept, a logical extension of existing ideas. Working on an established field of play can have its drawbacks too, especially for established players. As Enzo Torresi (President of NetFrame Systems) said, "The only reason God could create the world in six days was because He didn't have to worry about the installed base." Backwards compatibility is the bane of the systems designer. You can't (or shouldn't!) ship new products which don't interoperate with the products you shipped last year. It's a great way to lose customers. We had no such problems with Ethernet in 1980. It was more than a clean sheet of paper. It was an empty book. Don't Know Much About History, Don't Know Much Technology... In the early-mid 1970s, Robert Metcalfe and his group at Xerox's Palo Alto Research Center (PARC) invented and implemented an early Ethernet system. This became widely used within Xerox, becoming a key part of their Alto computer system (which was never commercialized). The Alto was the basis for the later, commercial Xerox Star, and in many ways, the Apple Macintosh. During 1979, Xerox, together with Digital Equipment Corporation and Intel, worked to transform the core Ethernet work done at PARC into a network standard, implementable in silicon and suitable for volume use and manufacture by a wide variety of companies. Employees from each of the three companies worked together from 1979 through to the publication of the Version 1.0 specification in September, 1980. (A Version 2.0 was published in November, 1982. The major change was the inclusion of standard Network Management capabilities.) While the original technology was functional, it was not a complete design. The DEC-Intel-Xerox team solved the problems of building large networks, algorithm stability, electrical and system performance, installability, reliability, cost, etc. The resulting design used the same basic principles as Metcalfe's prototype (it was still a CSMA/CD bus), but bore few other similarities. The changes included: Electrical signaling Cable types, connectors, etc. Packet formats CSMA/CD and backoff algorithm, CRC calculation System timing, Network Management primitives, etc. The result was a well-specified (anyone could build a compatible product from the specifications) system that could support all those applications we thought about that didn't yet exist. Too much? Too Little? Too Late? When the Ethernet technology was first exposed to the market, we drew lots of criticism: --It's overkill (who needs 10 Mb/s?) --It costs too much (controller boards were $1000-4000, without software, transceivers, etc.), --I don't understand it; it's too complicated. Of course, all of this was true. In 1980-82. No one needed 10 Mb/s. There was hardly a computer around that could keep up with that data rate, much less do anything useful with the information at that speed. A common technology in use at the time was Corvus Systems' OmniNet, a 1 Mb/s twisted-pair bus, used primarily for disk sharing among Apple II computers. We resisted the temptation to develop what the market needed at the time. There was a vision of distributed databases, interoperability, and multi-vendor networks that exceeded the capabilities of simple technology. It was more important to put an infrastructure in place that could support the development of a wide variety of applications, and have a long enough product life to allow those applications to grow without having to tear out the underpinnings every few years. It's like building a two-lane road to a new frontier; It will get you there now, but will be obsolete by the time the frontier is developed. Better to build a superhighway, and let it be empty for a while. There will be people to use it soon enough. (No surprise that two-thirds of the Ethernet triumvirate were in California!) I Can See Clearly Now, the Rain is Gone. The original Ether-thinking was conscious, long-term planning. It wasn't intended to be some nifty new technology that would give a competitive advantage to the developers. That's why we opened the design and architecture from the beginning. Any disadvantage incurred by allowing competition to flourish was offset by the increase in the size of the total market. Networks are only truly useful when everyone does it. Even a small piece of the pie is adequate, if the pie is huge. We used a 20 year product life as our model, expecting that installations and quantities would ramp up over the first 5-10 years, and then taper off as middle age set in, and some new technology emerged. This was before there was even a complete system design; no silicon, no independent networking companies, no applications, nothing. It's interesting that we aren't hearing the same complaints today about FDDI (other than cost, of course!). The reason is that we have learned the Ethernet lesson of letting the market and applications develop to use the technology as it matures. FDDI-based systems today do not take full advantage of the technology; neither the available silicon, the protocols we commonly use (today), nor the attached systems can truly exploit the full capability of the channel. But the FDDI community is thinking and planning for the future. They learned from the Ethernet experience how fast one can go from overkill to underpowered. We saw Ethernet as the "UART of the 90s". In 1980, no reasonable manufacturer built a computer without an RS-232 port. (UART stands for Universal Asynchronous Receiver/Transmitter. It is the key component of a serial port.) Even if you didn't have an immediate use for it, you put one in anyway, because it gave your users flexibility. Our vision was that in 1990, computer manufacturers would put networking into every machine, for the same reasons. Look what they've done to my song, Ma! Virtually all of that vision came true. Look at Sun workstations, DEC VAXen, and Apple Macintoshes. Networking is an integral part of the product. Every Sun comes with an Ethernet port; every Mac with a LocalTalk connection. The only way to connect terminals to (the larger) VAXen is through Ethernet, Terminal Servers, and LAT (Local Area Transport). The business truly evolved to exploit the technology that was offered. In fact, many of the successful networking companies today were started by those very people who worked on the original Ethernet technology. Founders and key personnel at 3Com, Sun Microsystems, Xyplex, Metaphor, Industrial Networking, Apple, Racal-Interlan, Wellfleet Communications, Ultra Technologies, Ascent Communications and Networks & Communications all came from the original Ethernet specification work team. The LAN business has exploded during the 1980s, in parallel with PCs, to totally transform information technology compared with 1980. LAN hardware, LAN VARs, third-party installers and support, thousands of software applications; none of this could have existed without the core technology and standards. What may be more interesting are all of the things that we didn't foresee that have affected our business. "No one predicted the emergence of twisted pair as the medium of choice," says Bob Printis, Manager of Systems Architecture at Xerox's Palo Alto Research Center, and one of the few team members still with their original company. The original Ethernet was coaxial-cable based. This invariably required the installation of new cable to implement an Ethernet LAN. As the technology became a commodity (LANs were no longer exciting in and of themselves), people became more concerned with "mundane issues" such as wiring up one's building. It turns out that issues like these have become much more important than the communications system in use on that wire. The reasons twisted pair wiring is popular have nothing to do with data rates, or electrical characteristics. They have to do with ease of installation, reconfiguration, and cable management. During the Ethernet design, we never realized the extent to which these issues would overshadow electrical performance. Twisted pair has worse noise performance, higher bit error rates, and can run at LAN data rates only over much shorter lengths than coaxial cable or fiber. But users are willing to live with these restrictions in exchange for the administrative advantages it offers. As in many other facets of life, people are willing to give up a lot for convenience. Don't you Care? Don't Yoo-ou Care?? Take a look in an old issue of this magazine (or any publication covering the networking industry). Go back to 1980-84. You will find articles touting the superiority of baseband to broadband. Or of broadband to baseband. Or of Token Ring/Ethernet/Token Bus/Slotted Rings, etc. to each other. You don't see these anymore. The network wars are over. And everybody has won. (Well, almost everybody.) When networking consisted solely of technology, technology was the subject of controversy. The fundamental building blocks of our business were just being cast, and everyone argued over the shape and color of the bricks. But today the technology is pass. There is little excitement over a new networking chip, another terminal server, a new bridge or router. There used to be arguments, in the standards bodies and trade press, over such minutiae as preamble bits, frame formats, type and length fields, checksum algorithms, and address lengths. While all of these things were ultimately decided, it turns out that it really didn't matter what the decisions were! The important thing today is that they were decided, and we could get on with the business of networking. The reason these were not really important is because networking is not technology. Today, hardly anyone cares about the technology (as long as it works). There are only three things users really care about today: (1) What applications can I run on my network? (What can it do for me?) (2) How should I wire my building? (You only get one chance to do it right.) (3) How do I manage the network effectively? Users are not concerned with the shape of the connector, the color of the cable, or the formats of the bits on the wire. It's not Token Ring vs. Ethernet, it's applications which run on Token Ring vs. applications which run on Ethernet. To the extent that applications, wiring systems, and network management are technology-independent, the underlying network characteristics become invisible and unimportant. The only vestige of their presence is performance. But there is rarely a perceptible performance difference once all the layers of software, server bottlenecks, and disk latencies are inserted between the user and the wire. It don't come easy, you know it don't come easy! It is nice to think that smart people can look at a problem, figure out the solution, write it down, and tell everyone about it. It's also nice to win the lottery, but the probabilities of the two events are roughly equal. What was published as the Ethernet "Blue Book" in 1980 was just the results of all the discussions, tests, mistakes, and negotiations that went on for more than a year before release. There were really more variations than one can imagine. At various stages in its development, Ethernet had: -- Preambles from 1 to 64 bits long -- A variety of different Collision Detect methods -- 16 bit CRC -- HDLC framing (flag characters and bit stuffing) -- Address lengths from 32 through 64 bits This last item is especially interesting. The (ultimately agreed-to) Ethernet scheme of 48 bit universal addressing was accepted and adopted by the IEEE 802 and FDDI network standards. But with only (!) 48 bits, you need some form of address administration to ensure that no two stations have the same address. This is done by allocating blocks of addresses to vendors, from which they are individually responsible for assigning unique addresses to their products. But with a 64 bit address space, a station could select an address at random, and the probability that two stations on the same network had the same address would be insignificant! We went through the mathematical analysis 10 years ago, and proved it (at least to ourselves). "But no one would have believed us," said Printis. "We would have had to fight an endless battle on that one." This became especially painful for Printis, who initially inherited the responsibility of assigning the vendor address blocks correctly. ....and if we had the chance to do it all again, tell me, would we? We surely would, but not exactly the same way. It's such a luxury to see with hindsight, but let's indulge ourselves. If the original Etherneters could change anything, what would they change? Dave Redell, originally Principal Scientist with Xerox Business Systems, and now a Member of the Research Staff at Digital Equipment Corporation's Palo Alto Systems Research Laboratory would have set the maximum packet size higher than the current 1500 bytes. "There was nothing magic about that number," said Dave. "It was a compromise. The main concern at the time was the cost of memory." During the specification discussions, the packet size limit varied from around 600 bytes to as much as 10 Kilobytes. Longer packets make for more efficient channel utilization, but also increase the probability of both an error in the packet, and that there may be a collision on the next packet. But the overriding concern at the time was that simple (read "cheap") controllers would allocate a fixed, maximum size buffer for every received packet. With 1K and 4K RAMs being the norm (1979, remember?), this was a major concern. So, we compromised. 1500 bytes allows for 1K bytes of user data, plus any reasonable protocol overhead. "If it were longer, large file transfers would be faster, and we might have avoided some of the Token Ring-to-Ethernet bridging hassles," laments Redell. Bob Printis would have included a Length field and avoided the Ethernet vs. IEEE 802.3 wars. (The only significant difference between the two is the IEEE's use of the length field vs. Ethernet's use of a Type field.) "Of course, if we had done that, they [the IEEE] would have found another way to make it incompatible," said Bob. "At least we found a workaround for the problem." It is possible to make the two at least coexist by assigning all type field values to be numerically greater than the maximum length of 1500 bytes. This author would have saved every Ethernet user a lot of grief by not specifying that [expletive deleted] slide-latch connector (used on the cable between the station and the transceiver). "We really had good intentions. I was fed up with RS-232 connectors that fell off because the tiny screwdriver necessary to tighten them down was never handy. I just never realized that the slide latch was so flimsy and unreliable until it was too late. Ethernet installers around the world must curse me every day." ----End Article---- (C) 1990 Rich Seifert and Networks & Communications Consulting. All rights reserved. -- Rich Seifert Networks and Communications Consulting 21885 Bear Creek Way (408) 395-5700 Los Gatos, CA 95033 (408) 228-0803 FAX Send replies to: usenet at richseifert dot com |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
In article <usenet-3C8997.18232009032005@news.isp.giganews.com>,
Rich Seifert <usenet@richseifert.com.invalid> wrote: >In article <lImdnZFFMrNQk7LfRVn-vQ@rogers.com>, > James Knott <james.knott@rogers.com> wrote: > >> Rich Seifert wrote: >> >> >> Incidentally, I have every issue of Byte on the shelves behind me. >> > >> > You will find an article I wrote in the January 1990 edition, >> > chronicling the 10th anniversary of the Ethernet ("Blue Book") >> > Specification. A group of the original designers got together in my home >> > for a reunion party, which resulted in the article. >> >> Actually, it's the Jan 1991 issue, page 315. >> >> "Ethernet: Ten Years After" >> >> Perhaps you could post the text or a link to it here. I'm sure others would >> find it interesting. > >Sure, why not? > >Below find the original article *as I submitted it to the magazine*; >i.e., before the editor's got their hands on it. Note that even then, I >was using titles and/or lyrics from popular songs for section headings, >a practice I continued through my later books (a practice that the >editors of BYTE Magazine disagreed with). Even the original title of the >article was "Reflections of ... the Way Life Used to Be" (a line from an >old Supremes song) > >As you read it (*IF* you read it, that is) remember that it was written >in October 1990, a time when 10BASE-T was quite new, FDDI was emerging >as the next-generation LAN, and Fast/Gigabit Ethernet did not yet exist. > >Enjoy! > And ATM ("asyn transfer mode") was going to be better as desktop LAN infrastructure than any of these, according to my boss at the time. >----Begin Article---- > >Reflections of...the Way Life Used to Be > >One thing that differentiates humans from lower beings is their ability >to defer instant gratification for long-term pleasure (some humans, >anyway). One of the more difficult tasks in this regard is to hold onto >a fine wine long enough to allow it to reach its peak. You see it every >time you open the wine cabinet, reminding you of its wondrous pleasures >to delight the palate, but still you let it lie, to reap an even greater >reward later on. If you are really patient, the flavors that finally >roll across your tongue are further enhanced by the remembrance of all >those years of anticipation. > >I purchased a magnum of Cabernet Sauvignon from Heitz Cellars on >September 30, 1980, the day we completed and "signed-off" the >DEC-Intel-Xerox Ethernet Specification, Version 1.0. I planned to enjoy >it with the Ethernet team on the tenth anniversary of that day. We >recently reunited to enjoy that wine and to reflect on the evolution of >LANs over the past ten years. > >Imagine There's no Network, I Wonder if you Can? > >While it's never easy to expand the horizons of one's business, at least >today there is an established market for LANs. You can do the market >research, listen to network users, find their needs, and determine the >niches where new ideas and products can flourish. > >In 1980, none of this was possible. Imagine a world without networks: no >Novell/3Com/TOPS, no clients, no servers. No Token Ring, Ethernet, or >LocalTalk. No transceivers, wiring hubs, bridges or routers. No TCP/IP, >no OSI. No PCs! Networks involved either proprietary point-to-point >connections or leased lines from the telephone company, and 300 baud >modems were standard. This was the environment in which the industry, >and the DEC-Intel-Xerox partnership was in when we began our effort. We >had to go where no LAN had gone before. > >A blank sheet of paper is a scary proposition. Most engineers and >product marketers rarely get to work with one. You are usually designing >a product which is second- or third-generation, an incremental >improvement on an existing concept, a logical extension of existing >ideas. > >Working on an established field of play can have its drawbacks too, >especially for established players. As Enzo Torresi (President of >NetFrame Systems) said, "The only reason God could create the world in >six days was because He didn't have to worry about the installed base." >Backwards compatibility is the bane of the systems designer. You can't >(or shouldn't!) ship new products which don't interoperate with the >products you shipped last year. It's a great way to lose customers. > >We had no such problems with Ethernet in 1980. It was more than a clean >sheet of paper. It was an empty book. > >Don't Know Much About History, Don't Know Much Technology... > >In the early-mid 1970s, Robert Metcalfe and his group at Xerox's Palo >Alto Research Center (PARC) invented and implemented an early Ethernet >system. This became widely used within Xerox, becoming a key part of >their Alto computer system (which was never commercialized). The Alto >was the basis for the later, commercial Xerox Star, and in many ways, >the Apple Macintosh. > >During 1979, Xerox, together with Digital Equipment Corporation and >Intel, worked to transform the core Ethernet work done at PARC into a >network standard, implementable in silicon and suitable for volume use >and manufacture by a wide variety of companies. > >Employees from each of the three companies worked together from 1979 >through to the publication of the Version 1.0 specification in >September, 1980. (A Version 2.0 was published in November, 1982. The >major change was the inclusion of standard Network Management >capabilities.) > >While the original technology was functional, it was not a complete >design. The DEC-Intel-Xerox team solved the problems of building large >networks, algorithm stability, electrical and system performance, >installability, reliability, cost, etc. The resulting design used the >same basic principles as Metcalfe's prototype (it was still a CSMA/CD >bus), but bore few other similarities. The changes included: > > Electrical signaling > Cable types, connectors, etc. > Packet formats > CSMA/CD and backoff algorithm, > CRC calculation > System timing, > Network Management primitives, etc. > >The result was a well-specified (anyone could build a compatible product >from the specifications) system that could support all those >applications we thought about that didn't yet exist. > >Too much? Too Little? Too Late? > >When the Ethernet technology was first exposed to the market, we drew >lots of criticism: > >--It's overkill (who needs 10 Mb/s?) >--It costs too much (controller boards were $1000-4000, without >software, transceivers, etc.), >--I don't understand it; it's too complicated. > >Of course, all of this was true. In 1980-82. No one needed 10 Mb/s. >There was hardly a computer around that could keep up with that data >rate, much less do anything useful with the information at that speed. A >common technology in use at the time was Corvus Systems' OmniNet, a 1 >Mb/s twisted-pair bus, used primarily for disk sharing among Apple II >computers. > >We resisted the temptation to develop what the market needed at the >time. There was a vision of distributed databases, interoperability, and >multi-vendor networks that exceeded the capabilities of simple >technology. It was more important to put an infrastructure in place that >could support the development of a wide variety of applications, and >have a long enough product life to allow those applications to grow >without having to tear out the underpinnings every few years. It's like >building a two-lane road to a new frontier; It will get you there now, >but will be obsolete by the time the frontier is developed. Better to >build a superhighway, and let it be empty for a while. There will be >people to use it soon enough. (No surprise that two-thirds of the >Ethernet triumvirate were in California!) > >I Can See Clearly Now, the Rain is Gone. > >The original Ether-thinking was conscious, long-term planning. It wasn't >intended to be some nifty new technology that would give a competitive >advantage to the developers. That's why we opened the design and >architecture from the beginning. Any disadvantage incurred by allowing >competition to flourish was offset by the increase in the size of the >total market. Networks are only truly useful when everyone does it. Even >a small piece of the pie is adequate, if the pie is huge. > >We used a 20 year product life as our model, expecting that >installations and quantities would ramp up over the first 5-10 years, >and then taper off as middle age set in, and some new technology >emerged. This was before there was even a complete system design; no >silicon, no independent networking companies, no applications, nothing. > >It's interesting that we aren't hearing the same complaints today about >FDDI (other than cost, of course!). The reason is that we have learned >the Ethernet lesson of letting the market and applications develop to >use the technology as it matures. FDDI-based systems today do not take >full advantage of the technology; neither the available silicon, the >protocols we commonly use (today), nor the attached systems can truly >exploit the full capability of the channel. But the FDDI community is >thinking and planning for the future. They learned from the Ethernet >experience how fast one can go from overkill to underpowered. > >We saw Ethernet as the "UART of the 90s". In 1980, no reasonable >manufacturer built a computer without an RS-232 port. (UART stands for >Universal Asynchronous Receiver/Transmitter. It is the key component of >a serial port.) Even if you didn't have an immediate use for it, you put >one in anyway, because it gave your users flexibility. Our vision was >that in 1990, computer manufacturers would put networking into every >machine, for the same reasons. > >Look what they've done to my song, Ma! > >Virtually all of that vision came true. Look at Sun workstations, DEC >VAXen, and Apple Macintoshes. Networking is an integral part of the >product. Every Sun comes with an Ethernet port; every Mac with a >LocalTalk connection. The only way to connect terminals to (the larger) >VAXen is through Ethernet, Terminal Servers, and LAT (Local Area >Transport). > >The business truly evolved to exploit the technology that was offered. >In fact, many of the successful networking companies today were started >by those very people who worked on the original Ethernet technology. >Founders and key personnel at 3Com, Sun Microsystems, Xyplex, Metaphor, >Industrial Networking, Apple, Racal-Interlan, Wellfleet Communications, >Ultra Technologies, Ascent Communications and Networks & Communications >all came from the original Ethernet specification work team. > >The LAN business has exploded during the 1980s, in parallel with PCs, to >totally transform information technology compared with 1980. LAN >hardware, LAN VARs, third-party installers and support, thousands of >software applications; none of this could have existed without the core >technology and standards. > >What may be more interesting are all of the things that we didn't >foresee that have affected our business. "No one predicted the emergence >of twisted pair as the medium of choice," says Bob Printis, Manager of >Systems Architecture at Xerox's Palo Alto Research Center, and one of >the few team members still with their original company. The original >Ethernet was coaxial-cable based. This invariably required the >installation of new cable to implement an Ethernet LAN. > >As the technology became a commodity (LANs were no longer exciting in >and of themselves), people became more concerned with "mundane issues" >such as wiring up one's building. It turns out that issues like these >have become much more important than the communications system in use on >that wire. The reasons twisted pair wiring is popular have nothing to do >with data rates, or electrical characteristics. They have to do with >ease of installation, reconfiguration, and cable management. During the >Ethernet design, we never realized the extent to which these issues >would overshadow electrical performance. Twisted pair has worse noise >performance, higher bit error rates, and can run at LAN data rates only >over much shorter lengths than coaxial cable or fiber. But users are >willing to live with these restrictions in exchange for the >administrative advantages it offers. > >As in many other facets of life, people are willing to give up a lot for >convenience. > >Don't you Care? Don't Yoo-ou Care?? > >Take a look in an old issue of this magazine (or any publication >covering the networking industry). Go back to 1980-84. You will find >articles touting the superiority of baseband to broadband. Or of >broadband to baseband. Or of Token Ring/Ethernet/Token Bus/Slotted >Rings, etc. to each other. You don't see these anymore. The network wars >are over. And everybody has won. (Well, almost everybody.) > >When networking consisted solely of technology, technology was the >subject of controversy. The fundamental building blocks of our business >were just being cast, and everyone argued over the shape and color of >the bricks. But today the technology is pass. There is little excitement >over a new networking chip, another terminal server, a new bridge or >router. > >There used to be arguments, in the standards bodies and trade press, >over such minutiae as preamble bits, frame formats, type and length >fields, checksum algorithms, and address lengths. While all of these >things were ultimately decided, it turns out that it really didn't >matter what the decisions were! The important thing today is that they >were decided, and we could get on with the business of networking. >The reason these were not really important is because networking is not >technology. Today, hardly anyone cares about the technology (as long as >it works). There are only three things users really care about today: > >(1) What applications can I run on my network? (What can it do for me?) >(2) How should I wire my building? (You only get one chance to do it >right.) >(3) How do I manage the network effectively? > >Users are not concerned with the shape of the connector, the color of >the cable, or the formats of the bits on the wire. It's not Token Ring >vs. Ethernet, it's applications which run on Token Ring vs. applications >which run on Ethernet. To the extent that applications, wiring systems, >and network management are technology-independent, the underlying >network characteristics become invisible and unimportant. The only >vestige of their presence is performance. But there is rarely a >perceptible performance difference once all the layers of software, >server bottlenecks, and disk latencies are inserted between the user and >the wire. > >It don't come easy, you know it don't come easy! > >It is nice to think that smart people can look at a problem, figure out >the solution, write it down, and tell everyone about it. It's also nice >to win the lottery, but the probabilities of the two events are roughly >equal. > >What was published as the Ethernet "Blue Book" in 1980 was just the >results of all the discussions, tests, mistakes, and negotiations that >went on for more than a year before release. There were really more >variations than one can imagine. At various stages in its development, >Ethernet had: > >-- Preambles from 1 to 64 bits long >-- A variety of different Collision Detect methods >-- 16 bit CRC >-- HDLC framing (flag characters and bit stuffing) >-- Address lengths from 32 through 64 bits > >This last item is especially interesting. The (ultimately agreed-to) >Ethernet scheme of 48 bit universal addressing was accepted and adopted >by the IEEE 802 and FDDI network standards. But with only (!) 48 bits, >you need some form of address administration to ensure that no two >stations have the same address. This is done by allocating blocks of >addresses to vendors, from which they are individually responsible for >assigning unique addresses to their products. > >But with a 64 bit address space, a station could select an address at >random, and the probability that two stations on the same network had >the same address would be insignificant! We went through the >mathematical analysis 10 years ago, and proved it (at least to >ourselves). "But no one would have believed us," said Printis. "We would >have had to fight an endless battle on that one." This became especially >painful for Printis, who initially inherited the responsibility of >assigning the vendor address blocks correctly. > >...and if we had the chance to do it all again, tell me, would we? > >We surely would, but not exactly the same way. It's such a luxury to see >with hindsight, but let's indulge ourselves. If the original Etherneters >could change anything, what would they change? > >Dave Redell, originally Principal Scientist with Xerox Business Systems, >and now a Member of the Research Staff at Digital Equipment >Corporation's Palo Alto Systems Research Laboratory would have set the >maximum packet size higher than the current 1500 bytes. "There was >nothing magic about that number," said Dave. "It was a compromise. The >main concern at the time was the cost of memory." During the >specification discussions, the packet size limit varied from around 600 >bytes to as much as 10 Kilobytes. Longer packets make for more efficient >channel utilization, but also increase the probability of both an error >in the packet, and that there may be a collision on the next packet. But >the overriding concern at the time was that simple (read "cheap") >controllers would allocate a fixed, maximum size buffer for every >received packet. With 1K and 4K RAMs being the norm (1979, remember?), >this was a major concern. So, we compromised. 1500 bytes allows for 1K >bytes of user data, plus any reasonable protocol overhead. "If it were >longer, large file transfers would be faster, and we might have avoided >some of the Token Ring-to-Ethernet bridging hassles," laments Redell. > >Bob Printis would have included a Length field and avoided the Ethernet >vs. IEEE 802.3 wars. (The only significant difference between the two is >the IEEE's use of the length field vs. Ethernet's use of a Type field.) >"Of course, if we had done that, they [the IEEE] would have found >another way to make it incompatible," said Bob. "At least we found a >workaround for the problem." It is possible to make the two at least >coexist by assigning all type field values to be numerically greater >than the maximum length of 1500 bytes. > >This author would have saved every Ethernet user a lot of grief by not >specifying that [expletive deleted] slide-latch connector (used on the >cable between the station and the transceiver). "We really had good >intentions. I was fed up with RS-232 connectors that fell off because >the tiny screwdriver necessary to tighten them down was never handy. I >just never realized that the slide latch was so flimsy and unreliable >until it was too late. Ethernet installers around the world must curse >me every day." > >----End Article---- >(C) 1990 Rich Seifert and Networks & Communications Consulting. >All rights reserved. > > >-- >Rich Seifert Networks and Communications Consulting > 21885 Bear Creek Way >(408) 395-5700 Los Gatos, CA 95033 >(408) 228-0803 FAX > >Send replies to: usenet at richseifert dot com -- a d y k e s @ p a n i x . c o m Don't blame me. I voted for Gore. |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
Rich Seifert wrote:
> As you read it (IF you read it, that is) remember that it was written > in October 1990, a time when 10BASE-T was quite new, FDDI was emerging > as the next-generation LAN, and Fast/Gigabit Ethernet did not yet exist. Yes, I did read it, both this morning and 14 years ago. As I mentioned in another note, by the time ethernet came out, I had already been working on a computer network for a few years, though it was quite different from ethernet, though in some ways similar to token ring. |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 stillrunning?
It takes a brave man to admit he was behind this device of torture.
And yes, I cursed. Jay Drew Rich Seifert wrote: <<<SNIP>>>> > This author would have saved every Ethernet user a lot of grief by not > specifying that [expletive deleted] slide-latch connector (used on the > cable between the station and the transceiver). "We really had good > intentions. I was fed up with RS-232 connectors that fell off because > the tiny screwdriver necessary to tighten them down was never handy. I > just never realized that the slide latch was so flimsy and unreliable > until it was too late. Ethernet installers around the world must curse > me every day." > > ----End Article---- > (C) 1990 Rich Seifert and Networks & Communications Consulting. > All rights reserved. > > > -- > Rich Seifert Networks and Communications Consulting > 21885 Bear Creek Way > (408) 395-5700 Los Gatos, CA 95033 > (408) 228-0803 FAX > > Send replies to: usenet at richseifert dot com |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
James Knott wrote:
[snip] > Incidentally, one thing that really gets me, is all the names for a > BNC connector. It is not "British Naval Connector" or that other > common one with a couple of people's names. According to what I read > in Ham Radio Magazine, several years ago, a guy from Amphenol (IIRC) > said it's derived from: > > B - bayonet lock > N - N type (you can actually plug a male BNC into a female N, though > the lock won't work > C - compact (version of N series) Oh no...here we go again! :) -- hsb "Somehow I imagined this experience would be more rewarding" Calvin **************************ROT13 MY ADDRESS************************* Due to the volume of email that I receive, I may not not be able to reply to emails sent to my account. Please post a followup instead. ************************************************** ****************** |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
Rich Seifert <usenet@richseifert.com.invalid> wrote:
> Note that even then, I was using titles and/or lyrics from > popular songs for section headings, a practice I continued > through my later books (a practice that the editors of BYTE > Magazine disagreed with). Perhaps worried about copyright infringement? > As you read it (*IF* you read it, that is) remember that A wonderful read! Thanks for posting it. Imagine -- random network addresses. Finally a good use for those 128 bit IPv6 addresses. 64 bits route, 64 bits rand. I doubt it will happen given governmental influence. -- Robert |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
JD wrote:
> It takes a brave man to admit he was behind this device of torture. > And yes, I cursed. > > Jay Drew > > > Rich Seifert wrote: > <<<SNIP>>>> >> This author would have saved every Ethernet user a lot of grief by not >> specifying that [expletive deleted] slide-latch connector (used on the >> cable between the station and the transceiver). "We really had good >> intentions. I was fed up with RS-232 connectors that fell off because >> the tiny screwdriver necessary to tighten them down was never handy. I >> just never realized that the slide latch was so flimsy and unreliable >> until it was too late. Ethernet installers around the world must curse >> me every day." > I didn't have much experience with those latches on ethernet, but some terminals I used to service used them. They were certainly a royal pain in the... |
Re: Does anybody have 10base5, 1base5, starlan1, or 10broad36 still running?
In article <7%XXd.5824$WK2.743@newssvr30.news.prodigy.com>,
Robert Redelmeier <redelm@ev1.net.invalid> wrote: > > Imagine -- random network addresses. No need to "imagine" it. This is precisely what happens within AppleTalk, both at the Network layer (DDP), and the LocalTalk Data Link. Stations choose their station identifier at random (at least the first time), then ask if anyone else is using the address (repeated times). If no one responds, the station uses the randomly-selected identifier, and stores it locally. If the station is reset, or powered down/up, it will first try the address it used last time, again checking to see if anyone else started using it while the station was dormant. In general, stations will use the same address over long periods of time, particularly in unchanging network configurations. If stations are often added, moved, etc., the addresses will vary considerably over time. However, at any given time, each active station will have a unique address. -- Rich Seifert Networks and Communications Consulting 21885 Bear Creek Way (408) 395-5700 Los Gatos, CA 95033 (408) 228-0803 FAX Send replies to: usenet at richseifert dot com |
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