Re: [Dorset] Range of a Cat 5 Ethernet Signal
On 22/03/18 13:09, Terry Coles wrote: It's now working. Thanks for all help provided. Except that he forgot to push home one of the wires in the receptacle for the antenna and I didn't do a proper inspection Duh. We all have days like this. Don't be hard on yourself. Peter -- Next meeting: Bournemouth, Tuesday, 2018-04-03 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
Re: [Dorset] Range of a Cat 5 Ethernet Signal
It's now working. Thanks for all help provided. On Wednesday, 21 March 2018 14:59:20 GMT Terry Coles wrote: > The wires were terminated at each end using Ethernet cable receptacles (the > wall pattress type). These have the wire colours on a label on the rear of > the connector and all you have to do is feed the wires from each pair into > the correct blade and press home with the tool. We even had the proper > tool, so I'm fairly comfortable that he did the wiring correctly. Except that he forgot to push home one of the wires in the receptacle for the antenna and I didn't do a proper inspection Duh. > Tomorrow, we're going to try a different simple test; disconnect the antenna > and plug a laptop in. If we can see the web pages and ping the Pi at a > sensible rate, then we'll have moved forward a bit at least. From my laptop I got sub- 1 ms pings from the Raspberry Pi when plugged into the remote end of the armoured cable and around 4 ms pings over the WiFi. -- Terry Coles -- Next meeting: Bournemouth, Tuesday, 2018-04-03 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
Re: [Dorset] Range of a Cat 5 Ethernet Signal
On Wednesday, 21 March 2018 14:48:04 GMT Ralph Corderoy wrote: > You said the Belkin lets the phone (Pi?) get an IP address, but not > transfer data. Was one of T568A or T568B followed when matching pairs > of wires to pins? Well. I didn't actually do the wiring, but the guy who did do the work is a hardware engineer from way back. He's done a fair bit of Ethernet installations over the years, but only in his and other homes. The wires were terminated at each end using Ethernet cable receptacles (the wall pattress type). These have the wire colours on a label on the rear of the connector and all you have to do is feed the wires from each pair into the correct blade and press home with the tool. We even had the proper tool, so I'm fairly comfortable that he did the wiring correctly. Tomorrow, we're going to try a different simple test; disconnect the antenna and plug a laptop in. If we can see the web pages and ping the Pi at a sensible rate, then we'll have moved forward a bit at least. If that doesn't work then we'll know that the problem isn't the Antenna installation. -- Terry Coles -- Next meeting: Bournemouth, Tuesday, 2018-04-03 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
Re: [Dorset] Range of a Cat 5 Ethernet Signal
Hi Terry, > > https://en.wikipedia.org/wiki/Cat_5 might be of interest. > > Yes. We saw that before we even attempted it. You said the Belkin lets the phone (Pi?) get an IP address, but not transfer data. Was one of T568A or T568B followed when matching pairs of wires to pins? You know, there are only eight individual wires inside a cabling jacket. So why not just terminate them at random, as long as you use the same scheme at both ends and you're consistent between cables? Well... that's a bad idea. There are standards in place for a reason. The cabling standards take into consideration just how the cables are twisted and placed in the jacket. If you deviate from those standards, you risk introducing noise and inefficiency into your cable plant that can have a negative impact on overall network performance. The standards I speak of are known as EAI/TIA-568-A and B and dictate the method by which data cables should be terminated. https://www.techrepublic.com/blog/10-things/10-things-you-shouldnt-do-when-running-network-cable/ Avoid swapping two lines between different pairs. This creates crosstalk. This is rectified by correctly pairing the pins. Crosstalk creates errors in Ethernet, and is more significant with 1GB Ethernet and up, as these standards use all 4 pairs. (10 Base/T and 100 Base/T Ethernet use only 2 pairs, thus swapping two wires in a 4 pair cable has only a 50% chance of affecting 10 Base/T and 100 Base/T Ethernet communications.) https://en.wikipedia.org/wiki/TIA/EIA-568-B#Wiring Cheers, Ralph. -- Next meeting: Bournemouth, Tuesday, 2018-04-03 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
Re: [Dorset] Range of a Cat 5 Ethernet Signal
Hi Bob, > Pi's will be built to the spec although there was a rumour of some > made without the isolation transformer in the socket. They were... > I'd expect to have seen a safety recall if this had been true. But they never left the factory without being fixed. https://www.raspberrypi.org/blog/manufacturing-hiccup/ Cheers, Ralph. -- Next meeting: Bournemouth, Tuesday, 2018-04-03 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
Re: [Dorset] Range of a Cat 5 Ethernet Signal
On Wednesday, 21 March 2018 13:53:13 GMT Bob Dunlop wrote: > The 125V is the minimum inter core DC insulation provided by the cable. > It's there because the cable may be carrying 57V DC PoE power and has > nothing to do with the signalling level which is about +-2V differential. Thanks. I've just been talking to the IT Manager at the company that I used to work for and he said much the same thing about the safety thing. It's good to know about the differential voltage. > Each end is transformer coupled with about 1500V isolation. Again because > of spec. It's an important safety as cables may be used for interbuilding > connections. Thanks. > Pi's will be built to the spec although there was a rumour of some made > without the isolation transformer in the socket. I'd expect to have seen > a safety recall if this had been true. Thanks. > > I was wondering how much people knew about commercial switches and whether > > they specify a maximum cable length? > > Yes the spec says 100m. From what you've said above, consumer grade devices (including the Pi) should also be good for 100 m then? > You can also get extenders that convert the signals (and often protocols) > to non-Ethernet signalling for covering long distances. Good ones cost more > that the rest of your kit combined. We normally convert to twin fiber > optic for longhaul. I've found some extenders that are good for 3 km! At ~£300 each that would cost more than the whole of my budget for the Webserver, the Bells system *and* the Lighting we did two years ago ;-( -- Terry Coles -- Next meeting: Bournemouth, Tuesday, 2018-04-03 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
Re: [Dorset] Range of a Cat 5 Ethernet Signal
On Wed, Mar 21 at 12:36, Terry Coles wrote: ... > I'm think more about the specifications of the driver/receivers in the two > devices. That spec that you referenced says that the maximum operating > voltage is 125 V, but we're not going to get that from a Raspberry PI! I > haven't managed to find anything on that aspect of the spec, but as I > understand it, each driver/receiver pair is current driven, so the driver > increases the voltage until the current required is achieved. I would expect > cheap switches (especially ones that run off low voltage DC (5 V for the TP- > Link and 12 V for the Belkin) would struggle to get the current after 40 -50 > metres or so. The 125V is the minimum inter core DC insulation provided by the cable. It's there because the cable may be carrying 57V DC PoE power and has nothing to do with the signalling level which is about +-2V differential. Each end is transformer coupled with about 1500V isolation. Again because of spec. It's an important safety as cables may be used for interbuilding connections. I've never seen a sub spec driver that wasn't just plain faulty/broken, well maybe some early D-link switches in the early 1990's. Similarly there isn't an Ethernet+ option despite what some marketing departments think. It's built to spec or it isn't Ethernet. Pi's will be built to the spec although there was a rumour of some made without the isolation transformer in the socket. I'd expect to have seen a safety recall if this had been true. > I was wondering how much people knew about commercial switches and whether > they specify a maximum cable length? Yes the spec says 100m. > Finally, can Ethernet boosters be obtained, or can we only get away with a > repeater half-way down the cable run? By repeater I assume you mean a bridge or switch. I believe the spec says you can only have three but that may have been repealed. You can also get extenders that convert the signals (and often protocols) to non-Ethernet signalling for covering long distances. Good ones cost more that the rest of your kit combined. We normally convert to twin fiber optic for longhaul. -- Bob Dunlop -- Next meeting: Bournemouth, Tuesday, 2018-04-03 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
Re: [Dorset] Range of a Cat 5 Ethernet Signal
On Wednesday, 21 March 2018 12:21:44 GMT t...@ls83.eclipse.co.uk wrote: > it solid copper or copper-clad aluminium). For what it's worth, I have a > long exterior cable run of around 100m with POE with a TP-Link or > Netgear POE switch at the near end, fairly new installation so Cat 6, > but running at 100MHz. Are the switches commercial grade or consumer grade? See my response to Ralph. -- Terry Coles -- Next meeting: Bournemouth, Tuesday, 2018-04-03 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
Re: [Dorset] Range of a Cat 5 Ethernet Signal
On Wednesday, 21 March 2018 12:17:14 GMT Bob Dunlop wrote: > By the book 1Gbps, 100Mbps, and 10Mbps should all support 100m. Yes; see my response to Ralph. > Dodgy termination, cable or connectors will severely reduce the range. See also my response to Ralph. This cable passes the tests we've performed using the fairly cheap Ethernet cable tester that we have. > Try forcing a drop of the line speed to 10Mbps, often works in dodgy > situations. Users who don't check the specs, cables crushed by water > pressure, let's try it any way etc. > > ethtool -s $DEVICE speed 10 duplex full > > Also "ethtool $DEVICE" will show you the current line settings. > > $DEVICE is probably eth0 or net0 BTW. If all else fails, we'll give this a try. I still think that this might be the limited line voltage that we have available. -- Terry Coles -- Next meeting: Bournemouth, Tuesday, 2018-04-03 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
Re: [Dorset] Range of a Cat 5 Ethernet Signal
On Wednesday, 21 March 2018 12:46:38 GMT Ralph Corderoy wrote: > > > Is it Cat 5 or 5e? > > > > Probably Cat 5e, but I didn't specify it. > > There's normally tiny writing repeated down its length on the stuff I've > seen? This is armoured and I don't recall seeing anything on the outside of the cable; it's just a uniform black around 1-2 cms in diameter. Under the outer sheath there is the armour made of stranded steel. Underneath that is another black sheath and then the screen (aluminium I think ) and then the four pairs of conductors. I'll ask tomorrow what the cable spec is. -- Terry Coles -- Next meeting: Bournemouth, Tuesday, 2018-04-03 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
Re: [Dorset] Range of a Cat 5 Ethernet Signal
Hi Terry, > > Is it Cat 5 or 5e? > > Probably Cat 5e, but I didn't specify it. There's normally tiny writing repeated down its length on the stuff I've seen? Cheers, Ralph. -- Next meeting: Bournemouth, Tuesday, 2018-04-03 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
Re: [Dorset] Range of a Cat 5 Ethernet Signal
On Wednesday, 21 March 2018 11:45:15 GMT Ralph Corderoy wrote: > https://en.wikipedia.org/wiki/Cat_5 might be of interest. Yes. We saw that before we even attempted it. We always knew that the poor old Pi might not be man enough for the job, but hoped we could get away with using a switch to help drive the lines. > Is it Cat 5 or 5e? Stranded or solid core? What's the margin of error Probably Cat 5e, but I didn't specify it. It is solid core; we connected it using insulation displacement connectors at each end. > on the 70 m? :-) What else is lying alongside it to interfere? How > long has it been there? We bought a 100 m roll of cable and cut off around 30 m at the end. There is probably another 3-4 m of drop cables at the antenna end and 0.5 m at the Pi end. There is nothing to interfere as far as we know. The first 30 m or so is buried alongside a plastic water pipe; the rest runs along a hedge line and is attached to a barbed wire fence. > https://en.wikipedia.org/wiki/Cat_5#Maximum_cable_segment_length says > 100 m, and implies that's 90 m of solid core with patch cables at the > ends, but don't just read that bit of the page. :-) We didn't. > There's test equipment like Fluke's that I've seen mentioned a lot, but > mainly alongside them being good but expensive. :-) > http://www.flukenetworks.com/enterprise-network/network-testing/CableIQ-Qual > ification-Tester We have a fairly cheap Ethernet tester, which shows that all terminations are good on both the slow and fast speed settings. I'm think more about the specifications of the driver/receivers in the two devices. That spec that you referenced says that the maximum operating voltage is 125 V, but we're not going to get that from a Raspberry PI! I haven't managed to find anything on that aspect of the spec, but as I understand it, each driver/receiver pair is current driven, so the driver increases the voltage until the current required is achieved. I would expect cheap switches (especially ones that run off low voltage DC (5 V for the TP- Link and 12 V for the Belkin) would struggle to get the current after 40 -50 metres or so. I was wondering how much people knew about commercial switches and whether they specify a maximum cable length? Finally, can Ethernet boosters be obtained, or can we only get away with a repeater half-way down the cable run? BTW. The fall-back is to move the server to the same location as the Antenna (this is a TP-Link TL-WA7210N Customer Premises Equipment). We will have to mount the server into an IP65 case, but we do have main available. -- Terry Coles -- Next meeting: Bournemouth, Tuesday, 2018-04-03 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
Re: [Dorset] Range of a Cat 5 Ethernet Signal
Hi Terry On 21/03/18 11:07, Terry Coles wrote: Hi, We've just re-connected our WMT Webserver with the antenna in its new location at the far end of the site. The server is currently in the old location so there is about 70 m of armoured Cat 5 cable between the two. The Question is; do we need something a bit more powerful at each end to drive the lines or do we need something at both ends? 70m ought to be fine but may depend on the quality of the cable (i.e. is it solid copper or copper-clad aluminium). For what it's worth, I have a long exterior cable run of around 100m with POE with a TP-Link or Netgear POE switch at the near end, fairly new installation so Cat 6, but running at 100MHz. I have two switches to hand; a very cheap TP-Link and a bit more expensive Belkin job. With the TP-Link, only the near end indicator lights and with the Belkin, both indicators come on. This leads me to believe that something a bit more powerful might do the trick. When the Belkin is installed the phone gets an IP address, but fails to retrieve the data. Could be the switch. Cheers Tim -- Next meeting: Bournemouth, Tuesday, 2018-04-03 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
Re: [Dorset] Range of a Cat 5 Ethernet Signal
On Wed, Mar 21 at 11:07, Terry Coles wrote: > Hi, > > We've just re-connected our WMT Webserver with the antenna in its new > location at the far end of the site.?? The server is currently in the old > location so there is about 70 m of armoured Cat 5 cable between the two.?? > The Question is; do we need something a bit more powerful at each end to > drive the lines or do we need something at both ends? By the book 1Gbps, 100Mbps, and 10Mbps should all support 100m. Dodgy termination, cable or connectors will severely reduce the range. Try forcing a drop of the line speed to 10Mbps, often works in dodgy situations. Users who don't check the specs, cables crushed by water pressure, let's try it any way etc. ethtool -s $DEVICE speed 10 duplex full Also "ethtool $DEVICE" will show you the current line settings. $DEVICE is probably eth0 or net0 BTW. -- Bob Dunlop -- Next meeting: Bournemouth, Tuesday, 2018-04-03 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
Re: [Dorset] Range of a Cat 5 Ethernet Signal
Hi Terry, > The server is currently in the old location so there is about 70 m of > armoured Cat 5 cable between the two. https://en.wikipedia.org/wiki/Cat_5 might be of interest. Is it Cat 5 or 5e? Stranded or solid core? What's the margin of error on the 70 m? :-) What else is lying alongside it to interfere? How long has it been there? https://en.wikipedia.org/wiki/Cat_5#Maximum_cable_segment_length says 100 m, and implies that's 90 m of solid core with patch cables at the ends, but don't just read that bit of the page. :-) There's test equipment like Fluke's that I've seen mentioned a lot, but mainly alongside them being good but expensive. :-) http://www.flukenetworks.com/enterprise-network/network-testing/CableIQ-Qualification-Tester Cheers, Ralph. -- Next meeting: Bournemouth, Tuesday, 2018-04-03 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
[Dorset] Range of a Cat 5 Ethernet Signal
Hi, We've just re-connected our WMT Webserver with the antenna in its new location at the far end of the site. The server is currently in the old location so there is about 70 m of armoured Cat 5 cable between the two. The Question is; do we need something a bit more powerful at each end to drive the lines or do we need something at both ends? I have two switches to hand; a very cheap TP-Link and a bit more expensive Belkin job. With the TP-Link, only the near end indicator lights and with the Belkin, both indicators come on. This leads me to believe that something a bit more powerful might do the trick. When the Belkin is installed the phone gets an IP address, but fails to retrieve the data. Ultimately we will have a switch about halfway along anyway, but we're not ready for that yet. Thoughts? Sent from Blue -- Next meeting: Bournemouth, Tuesday, 2018-04-03 20:00 Meets, Mailing list, IRC, LinkedIn, ... http://dorset.lug.org.uk/ New thread: mailto:dorset@mailman.lug.org.uk / CHECK IF YOU'RE REPLYING Reporting bugs well: http://goo.gl/4Xue / TO THE LIST OR THE AUTHOR
