Eventually the only thing left that we had not swapped out was a BNC 'T' connector at the back of the MAU of chopper itself, the one that was used to put it on the coax bus.
My buddy Jasper and I both looked at each other at the same moment around 4 am or so, bleary from sleep 'that can't possibly be it', let's swap it out. And sure enough that was it.
Apparently that particular 'T' connector had electrical capabilities unlike any other 'T' connector produced before or after. It managed to filter out 'ping' reply packets from the IP address of the server reported as down...
Why not fiber? Its fragile, expensive, hard to pull, and not well suited to temporary situations, precut armoured fiber is very expensive - coax is fragile, but cheap and easy to terminate.
http://www.amazon.com/gp/aw/d/B008EQ4BQG?pc_redir=1414247414...
Super-G is one implementation but you can also roll your own and on more channels giving you up to 300 Mbit on fairly long hauls.
http://en.wikipedia.org/wiki/Channel_bonding#Wi-Fi
Asus N56U claims to do this out of the box.
http://www.blackbox.com/Store/Detail.aspx/LinkGain-Ethernet-...
I used it a lot for gaming (LAN parties), back in the days when Ethernet (that's thin coax ethernet) cards were still expensive. Arcnet equipment could be obtained for cheap (or even free), the speeds were enough for gaming (Doom, Quake, Descent), the DOS drivers were great, and overall it was a great solution which Just Worked. Most importantly, it didn't have the problem of one person bringing down the entire network just by disconnecting the cable at his station, which thin ethernet had.
See http://en.wikipedia.org/wiki/ARCNET for more details.
One large job I particularly remember was in the admin block of a large seaside holiday and entertainment complex. The block was several floors high and the apex roof was 'U' shaped; when working in the roof space, you could either walk around the 'U' from end-to-end (a total length of about 200m), OR cut across the middle through a pair of external doors and across the central flat roof - but the roof was guarded by some VERY territorial and VERY big seagulls. Using the short cut was a risky business as the gulls would take flight and begin dive-bombing!
That's the 15-pin VGA-ish connector in the card pictured.
10 Mbit/s doesn't cut it apparantly.
I don't think you can take it as given that the network is the problem when you see an 'error establishing a database connection'. I'd start with looking at the database.
The "thick yellow wire" and the "coax" both had a single broadcast domain for all devices on the segment. You then linked segments with a bridge (so you could scale networks).
Some things I find interesting about them:
1) The idea is based on radio broadcast (ALOHANET). Since you're using radio broadcast there, a single collision domain makes sense. http://en.wikipedia.org/wiki/ALOHAnet. The protocol is best understood as "room full of people shouting at each other". Don't start talking if something else is, and if two people start at the same time, you both back off. Simple as that.
2) If two nodes try to transmit at the same time, you get a collision and both retry. The spec has a random retransmit timer to avoid immediate (and perpetual) recollision. Requires fair nodes...
3) The max cable length and packet size and related via the speed of light (in copper): http://www.wildpackets.com/resources/compendium/ethernet/pro...
4) It was (semi-)reasonable to use a "vampire tap" connector to dig through the insulation and into the core of a the "thick yellow" copper cable. Just don't wiggle it and cut the copper (or introduce too much of an edge and get signal reflection and hence more collisions).
5) When you had a copper connection between all the ports on your network, an etherkiller really meant something. (A cable, mains plug on one end, coax connecter on the other. Plug in and fry every network card on the segment). RJ-45 etherkillers are single-target. Pah.
A fair chunk of this network ran through their factory up in the factory roofspace. I used to climb these ridiculously high step ladders to reach up into the factory roof steelwork to install "vampire taps".
It used to scare the bejesus out of me, mostly due to an aversion to heights, the other being that the factories produced cotton thread, which during one of the processes requires the application of a fine mist of wax or light grease, I don't remember why. But every high up surface was deceivingly lubricated with a fine layer of wax or grease as a result of being kinetically atomised into the air by high speed thread spinners, rollers, spoolers and guides. To further focus your mind, there was also an opportunity of being impaled on these massive crane lifted pointy multi-spool holder things should you put a foot wrong (they were used to lift large bulk spools of rough spun cotton into even larger dying machines).
Although we had a proper coring tool my biggest fear was of creating a short between the shield and core and unf*cking that up a 30 ft step ladder in that environment would have ruined my day (we had to install these things on live segments, there was no downtime permitted). Fortunately the quality and accuracy of the tooling was good, the customer used the correct cable (not some cheap imitation) and my karma and anxiety levels could return to normal once the transceiver lights flickered into life.
Just thought I'd share my lasting memory and experience of 10BASE5 hands on work.
I spent many hours playing Doom and Warcraft 2 on exactly this setup! (Feeling a bit old now...)
(and yes thick ether standardly came with connectors on the end, I still have a roll somewhere, I have no idea why)
