Ethernet on a single pair--bye bye wi-fi

[brianl703]

My mom's computer was connected via an ethernet cable to the cablemodem. The cable was run under the carpet. This worked fine until she had tile installed--no more carpet, and no way to run the cable without it looking tacky or doing a LOT of work.

So I got a wireless router and a wireless card. That worked, but the wireless started having problems where the computer wouldn't get an IP address unless you repaired the connection. So I tried a USB wireless adapter. That worked fine for a while, then the same thing started happening with that adapter.

I have no idea what's going on with the wireless---I'm going to get rid of it. I'm sick of dealing with the intermittent problems.

There is an existing telephone cable run between where the cablemodem (which is also a EMTA for Cox telephone service) is and the computer, but it is only a 2-pair cable, one pair already used for the telephone line.

I found these devices made by ETS called Pair Savers. They claim to allow running 10baseT over a single pair. They're about $30 each and you need one for both sides of the connection. They are apparently a hybrid transformer similar to that used in telephones, which allows connecting a 2-wire circuit to a 4-wire circuit.

I got them today and they work as advertised. I'm testing them with a single pair of cat3 connecting them. I did have to set the computer to 10 meg/half duplex, but I was expecting that.

I'll install them this weekend. I expect they will work fine with the telephone cable, 10baseT was designed for telephone cable. I actually had them working with a regular two-wire flat telephone cord--definitely out of spec for 10baseT. (10baseT specs twisted pair cable, flat telephone cords aren't twisted pair).

http://www.etslan.com/Ethernet.htm

 

[greenaccord02]

That's some cool stuff. Very interesting solution to the problem.

 

[StevieC]

I'm more concerned that you are having so much problem with your wireless setup. I have 4 wireless devices using my internet on a pretty constant rate with no problem.

What kind of router / wireless cards are you using? Does your router have the latest firmware?

Could is be a wireless signal strength problem?

 

[MGregoir]

Wired is always much better than wireless LAN in about every way except portability. There's no excuse for a desktop to be on wireless.

 

[StevieC]

I disagree if done right wireless can be as fast or faster and just as reliable as a wired connection. The problem is we have so many cheesie routers that have problematic firmwares or are Chinese made and are garbage...

 

[TooManyWheels]

The wireless problem sounds like 2.4 GHz cordless phone interference, but that was probably your first thought.

 

[brianl703]

2.4 Ghz cordless phone is probably the most likely culprit. A microwave oven with worn out door hardware can also cause interference, but isn't likely to be used as much as a cordless phone.

It doesn't appear to be a signal strength problem, the router and the computer are within 30 feet of each other.

If this problem is indeed being caused by interference, I'll never find it without a spectrum analyzer...and then if I do find it, I don't exactly have the authority to tell whomever is using the cordless phone to stop, because they're interfering with my wireless.

Quote:
This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.


(2) means you have zero recourse if your wi-fi is getting interference.

This is why wi-fi is not as reliable as wired. Someone outside of your facility can make it unreliable--and you have no recourse to stop them.

 

[mstrjon32]

Wireless equipment burns out like it's going out of style, I don't care what the manufacturer is. I've burned out any number of cards and access points, including Cisco, Linksys (before they merged), Netgear, 3Com, Apple, DLink, Orinoco (probably the best of them all), etc. The Philips MiniPCI card in my laptop is now starting to fail, so I'll have to do something about that soon. I used to use wireless in my desktop but I just couldn't take how much it sucked anymore, and went back to copper.

Just thinking about how much money I've blown on [censored]-[censored] wireless equipment makes me feel ill.

 

[PandaBear]

Wireless equipment does not last forever, they are emission device and like your microwave oven, will gradually die. Don't expect it to work for 10 years like your wired DSL modem.

Almost all router, regardless of brands, are made in China. The good ones use good chipsets like Broadcom and Atheros; then the junk uses stuff like Marvel and Ralink. All 4 mentioned companies are AMERICAN. So there goes your Chinese made junk theory.

In theory you should be able to either switch to 802.11a and use a different frequency band to get around the interference problem, or try a different pair of components like a new router and new network card pair and see how they work. If the new pair works but the old one doesn't, then it is not interference, it is worn components.

If I were you I wouldn't touch the pair saver. You have a connection that come from the phone company and unless you cut it permanently from where it enter the house, you have a long wire set up to several thousand feet on one end, and who know what sort of interference and problem it may generate. Also who know what sort of quality and reliability testing have they done on this product? You probably won't find much troubleshooting info like the wireless routers and network adapter.

If I were you I would go buy a wireless router that can run DD-WRT and have good reliability, and then set it to client mode and have it connected to your mom's PC. Wireless router has more room inside so better cooling, and therefore last longer than the network cards. Also the benefit is you can use network cable to extend the location of each router to have optimal reception.

 

[brianl703]

Originally Posted By: PandaBear


In theory you should be able to either switch to 802.11a


802.11a equipment is pretty expensive. It would be cheaper for me to hire an electrician to install a cable and patch the drywall.

Quote:
If I were you I wouldn't touch the pair saver. You have a connection that come from the phone company and unless you cut it permanently from where it enter the house, you have a long wire set up to several thousand feet on one end, and who know what sort of interference and problem it may generate.


10baseT is about 20-year-old technology that was engineered to work on telephone cable, in the same physical cable as actual phone lines. When 10baseT came out there was no cat5 and not even cat3(there was AT&T DIW). Electromechanical 1a2 key telephone systems were still in fairly common use.

10baseT was designed with all of this in mind, to operate on existing telephone cable shared with existing telephone equipment, including, yes, rotary-dial phones with electromechanical ringers.

I hooked my first 10baseT network up with cat-nothing telephone cable I scavenged from a construction dumpster, and it worked fine. (You couldn't buy cat5 or cat3 at Home Depot back then).

In any case, the phone line here originates at an EMTA (for cable phone service), so it never leaves the house. Even if it did there would be no problem--I have mixed even 100baseT ethernet and regular analog phone lines in the same cat5 cable and it works fine.

Quote:
Also who know what sort of quality and reliability testing have they done on this product? You probably won't find much troubleshooting info like the wireless routers and network adapter.


I've done my own testing.

Troubleshooting wired Ethernet is a pretty straightforward process that I am quite familiar with.

Troubleshooting wireless Ethernet is not quite so straightforward---unless you happen to have a spectrum analyzer, among other uncommon pieces of test gear.

Quote:
If I were you I would go buy a wireless router that can run DD-WRT and have good reliability


Until something operating in the 2.4GHz range interferes with it. Then it's time to break out the spectrum analyzer I don't have to see what's going on.

(and then, most likely, not be able to do anything about it).

 

[brianl703]

http://standards.ieee.org/getieee802/

Might be interesting reading--all the Ethernet specs are there, for free.

 

[StevieC]

I have a few older wireless cards from when they first came out and they still work fine, also my first wireless router works just fine and it has to be 10+ years old. I don't buy the "It burns out" argument. That's just nonsense IMO.

 

[brianl703]

I'm not really sure what's going on. It only happened once when I was there and I thought it was a bad USB cable to the wireless adapter (the socket was bent). I replaced the USB cable and 3 days later I got a call saying it's not working right again.

I never got these complaints back when it was hooked up with a cable.

I think it's a cordless phone. That would make sense since I often come to look at it well past the hour at which you'd expect most people to be in bed and not yakking on the phone. Most complaints I get are during the day, when I can't be there to look at it.

 

[StevieC]

I have two phone lines in my house with 4 different cordless phones and one of them always seems to be going. We have 3 laptops always on the internet and no problem whatsoever?

Check your equipment maybe it's faulty or the cordless phone is interfering and shouldn't be.

In my old house the microwave used to scramble our WIFI and make the network disappear while running.

 

[greenaccord02]

If you reset the router and performed a hard power-down did the problem correct itself? I would wonder if a cache wasn't full or something. Try a firmware update. My router was trash until I upgraded the firmwase, it fixed a number of issues not the least of which was a problem with the amount of entries in the open connection cache.

 

[StevieC]

Try buying a router that is compatible with the Linux Firmware DD-WRT. I use this now and never have to reboot my router and never have those weird wireless pesky problems that others seem to encounter and that I had now and again before changing to DD-WRT

 

[brianl703]

I've installed them. The purists will have a heart attack:

I have a piece of cat5e, one side of which is connected to a wallplate (with an RJ11 for the phone adapter (blue/white pair) and an RJ45 for the pairsaver (orange/white pair)) on the back wall of the house, running up the side of the house about 3 feet to the telephone network interface where I spliced it (using Scotchlok UR connectors) to the existing phone cable that runs to the kitchen phone, where I again spliced it (also with Scotchlok UR connectors) to the phone cable I added a few years ago that runs around the doorframe inside the pantry to behind the computer. (The cable doesn't actually connect to the telephone network interface, the telephone network interface just provides a nice weatherproof place to splice it, since my mom no longer has Verizon phone service).

Oh, did I mention that the existing phone cable says "CAT 1" on it? (It's definitely twisted pair though and judging by the bumps in it looks to be two twists per foot).

On each of this chain of 3 separate pieces of "CAT 1", "CAT 5E", and "CAT 3" cable (all spliced together with Scotchloks!) is the Pairsaver, plugged into the ethernet card on the computer at one and and the router at the other.

I started pinging the gateway and dialed my mom's phone. The ringing signal isn't interfering at all, which is as I expected. (I've never seen that happen, though it's always cited as a reason you shouldn't mix ethernet and phone in the same cable).

So far, the performance is great and the ping times are less than a millisecond which I've NEVER seen on ANY wireless. (The ethernet card is set to 10 megabit/half duplex).

 

[StevieC]

DSL is mixing ethernet and phone calls last I checked...

But I guess its okay for the Tel Co. to do it...

Just not end users according to the purists.

I'm happy everything is working for you... I was just stating that Wireless if done right can be very reliable and fast, it's all the Chinese junk out there combined with the "I.T. kid next door" that gives it a bad name IMO. (Not suggesting this is you or your setup)

My ping times are very good, not 1ms but very fast and my new laptop is faster than my hard wired desktop... I download at 600K/Sec over my wireless network with lots of traffic, and my online games like Need for Speed work fine over wireless and I have seen these chop on hard wired connections on other computers.

I really think equipment and setup has a huge role to play with reliability.

 

[brianl703]

Originally Posted By: StevieC
DSL is mixing ethernet and phone calls last I checked...

But I guess its okay for the Tel Co. to do it...

Just not end users according to the purists.


The physical signaling for DSL is very different from Ethernet--much more complex. DSL really was designed to go on the same pair as analog telephone--Ethernet was only designed to share the same physical cable as Ethernet and not be affected by crosstalk from the analog telephone line. (Well, 100baseT4 and 100baseT2 can be affected by crosstalk from analog phone lines, but I have never seen any equipment designed for those standards).

Quote:
I'm happy everything is working for you... I was just stating that Wireless if done right can be very reliable and fast, it's all the Chinese junk out there combined with the "I.T. kid next door" that gives it a bad name IMO. (Not suggesting this is you or your setup)


Your neighbor's chinese junk that operates in the 2.4GHz range could cause problems with your wireless network.

Quote:
My ping times are very good, not 1ms but very fast and my new laptop is faster than my hard wired desktop...


My hard wired desktop will do around 300mbps on a gigabit lan. It'll saturate a 100mbps lan easily.

 

[brianl703]

This, by the way, is a Scotchlok UR connector:

Used by telcos worldwide for splicing wires.