Newbie: cheap cable tester?

There are several different types of measurements that have to be done, most over a range of frequencies. It's the sort of thing that is easy if you have the right tool, and cumbersome to impossible otherwise.

Looking around a bit and sampling some prices, there appear to be a number of tools available, including:

Ideal Lantek 6, about $6000 to $9000 Fluke DTX-1200, about $7000 to $13000 (possibly for the exact same thing) Fluke DSP-4000, about $6000 to $7000, DTX is the newer line Fluke Etherscope, about $20000-ish, possibly superceeded Agilent FrameScope 350 plus DualRemote 350 Agilent Wirescope 350, about $5000 Test-um NT950 Validator, about $1100

These are only a brief survey, not recommendations. I haven't used any of these; I've never heard of Test-um before. I have used the much older Fluke LanMeter (Cat 5); it was fairly simple for the ethernet tests (more complex for fibre tests.)

I see the Fluke DTX-1200 quoted at 9 seconds for a full Cat6 test in one place, and quoted at 12 seconds in another. I didn't look to see whether that's a general improvement over the lifetime of the product, or if special licenses or extras are needed for the faster testing.

Chris wrote in part:

Try it and see. You can always take two hot laptops with built-in GBE and run `ttcp` or `netperf`. Try across a known good patchcord to see what the machines are cabable of. Don't expect them to be able to saturate the link (120 MByte/s) but record what they can do (30-50) and see if the test links are close (1-5%). If the links are 12 or below, it's likely they've fallen back to 100, most likely due to a bad pair.

Walter has given you the pricing rundown on certification equipment. Simple continuity/wiremaps are much cheaper. You could also call a local dcom cabling contractor. If not busy, she should be able to certify the links for $20-50 each.

I expect less than 10% of all wiring has been certification tested, mostly due to the cost of test equipment. The wire that has been tested was mostly installed by govt/megacorps who always want a spec. They will occasionally save themselves some very nasty, hard to find network problems (split pair).

-- Robert

Keep in mind that the OP asked

If your split pair test failed it would be sufficient proof that it wouldn't work but if it didn't fail it wouldn't guarentee full speed service.

Well, the racetrack wouldn't find things like too much untwist, stretched or kinked cable. But it would find common things like opens, shorts, hi-resistance and split pairs. You pays your money and to takes your chances.

-- Robert

(snip)

It shouldn't be so hard to build a simple detector for split pairs, though I don't know that anyone has done it.

If they are terminated, and maybe even if they aren't, send a balanced signal down each pair, one at a time, and measure the signal on the other pairs. Though if one is actually trying to do it right, the probability of continuity on each wire (that is, pin 1 to pin 1, pin 2 to pin 2, etc.) being right and the pairs being wrong is fairly small. I used to know someone with a little box with eight LEDs that would plug into one end, and a transmitter for the other end. The LEDs should light in sequence if the pins were connected right. Simple, but will catch a large fraction of errors.

-- glen

(snip on cable testing systems)

True, but he also asked for cheap. Testing to the full cat 6 standard likely can't be done cheap, but there may be useful tests that could be done that are better than the simplest continuity test.

If there was demand for a cheaper tester someone would probably try to build one. There probably isn't quite enough.

-- glen

There also appears to be the Fluke CableIQ Qualification Tester, about $1000. According to the flukenetworks.com information,

Qualifies - Sees if your existing cabling has the bandwidth to support voice, 10/100, VoIP or Gigabit Ethernet

Troubleshoots -- shows why existing cabling cannot support the network's bandwidth requirement (e.g., crosstalk at 11 meters)

Hmmm, you might need the CIQ-GSV "CableIQ Gigabit Service Kit", which probably costs more.

This freebie will test throughput; (Ixia Qtest)

Also I use an on-line monitor on my machines which displays current, average, and max UL and DL in mbits or mbytes/sec. It is AnalogX Netstat Live from analogx.com

gr