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Old 01-23-2017, 06:36 AM   #1
grumpyskeptic
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Very low bandwidth due to long telephone extension cord or something else?


I am using Linux Mint 17.3 Rosa Cinnamon.

The bandwidth I get when downloading big files is only about 650kbs, a fraction of the two or three mbps that the ISP apparently provides. I live in an urban area, so I ought to get a reasonable service.

Could this low bandwidth be due to using an extension telephone line from the telephone wall socket to my modem-router which is about fifty feet long?

If that is the problem then it would be a waste of time and money to e.g. buy a new modem-router.

Thanks

Last edited by grumpyskeptic; 01-24-2017 at 04:26 AM.
 
Old 01-23-2017, 07:23 AM   #2
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Type the command "ifconfig" in a terminal window and check the output for transmit or receive errors.
 
Old 01-23-2017, 07:29 AM   #3
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Quote:
Originally Posted by grumpyskeptic View Post
I am using Linux Mint 17.3 Rosa Cinnamon.

The bandwidth I get when downloading big files is only about 650kbs, a fraction of the two or three mbps that the ISP apparently provides. I live in an urban area, so I ought to get a reasonable service.

Could this low bandwidth be due to using an extension telephone line from the telephone wall socket to my modem-router which is about thirty feet long?

If that is the problem then it would be a waste of time and money to e.g. buy a new modem-router.

Thanks
#1 I appreciate your providing the distro and version you are running. It is so common for questions to be raised without such information. In this case, it may not matter, but thank you!

#2 If that line is indeed telephone line, it is equivalent to network standard Cat-3 line and does not support very high bandwidth. Cat-5 is the lowest I would recommend. Common usage is Cat-5e, which may be over kill in this case. The new Cat-6 would certainly be overkill, as it is used to support 1000bt and higher. (I find Cat-5e supports 1000bt nicely for SHORT runs.) Your ISP is certainly not providing even 10BT, so cheap Cat-5 should suffice, but telephone wire could be causing your issue.

The above makes certain assumptions that may or may not be correct. In this case the information missing that would help us would be information about your networking, devices, and ISP.
Can you discuss your router, modem, ports (are they locked to a certain speed and duplex setting), and wired and wireless standards and settings as appropriate?
 
Old 01-23-2017, 07:32 AM   #4
pan64
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have you tried http://www.speedtest.net/ or similar already? Probably this is better: http://freeola.com/line-test/ or this: http://www.dslreports.com/tools/pingtest.
I would also try to discuss it with your ISP. I would rather say the quality of the cable is important, I guess in general it should work.
 
Old 01-23-2017, 07:47 AM   #5
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That depends on a few things. When using a line , length + grade of copper telephone wiring used, (how new is it vs how old is it over all: means inside the walls of your house and the line plugged into it).


Gold is the #1 conductor of electricity

copper is #2 conductor of electricity

that is why they have gold plating on connections, that just bottle neck as soon has the current leaves the level of gold almost instantly bottle necking as soon as it goes into the copper. (waste of money to get them is MO)

The length does have to do with data drop as well as crosstalk. (crosstalk being noise outside itself causing it to lose data) ex. wires too close together and not enough shielding on the wires.

The wire length too has it limits.
CAT5
Quote:
Using quality CAT 5 Cabling, good wiring practices and no EMI problems, the maximum recommended transmission line length between nodes for 10BaseT and 100TX is 100 Meters (about 329 feet). For Gigabit wiring using 1000BaseT operating at 350MHz, the limitation is 82 feet.


Quote:
There's one beautiful, simple equation that has it all, called the Shannon–Hartley theorem:

C=B⋅log2(1+S/N)

It says that over a channel with a given quality, the capacity (bit rate) C is proportional to the channel's bandwith B. The quality of the channel (signal vs. noise) hides within log2(1+S/N)

, and the bit rate includes redundancy (error checksums and the like).

The best data rate can be achieved with a low-noise installation of a channel that offers a high bandwith.

Of the wiring systems in question, a simple two-wire phone line will have the lowest bandwith and the worst noise properties (crosstalk and interference from neighboring lines, ...), twisted pair wires increase the bandwith and are more immune to external noise with an increasing "CAT number" (6 being better than 5e, being better than 5, ...) and systems with optical fibers are even better.

A telephone connection has an audio bandwith limited to a few kHz. Old systems had filters and the wires were often not capable of much more than the filter-defined bandwith. Digital subscriber lines (DSL) take advantage of the fact that many phone lines, when not being filtered, can take more than the mediocre audio bandwith of telephones. Beyond approx. 200 bps, it depends on the installation of the last mile and in your house (and your provider's willingness to use it in the best way). Typically, fiber can handle a greater bandwith than copper, but good quality can be achieved with copper, too.

Note: Someone selling you "Fiber to the Home" over copper wires is just doing (un-? clever?) marketing. Claude Shannon was way cooler, he didn't even care about the type of channel (copper, fiber, radio waves, whatever), he just looked at the bandwidth and the quality (signal-to-noise ratio). You can join Shannon and, like him, enjoy the theory and also don't care about the material of your wires. When I took my communication theory class at college, my professor was actually very right when he pointed out the beauty of shannon's work and said that the equation mentioned above was the E = mc2 of the information technology age.
Quoted information was gotten off of the internet.

Last edited by BW-userx; 01-23-2017 at 07:51 AM.
 
Old 01-23-2017, 09:59 AM   #6
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Are you using wifi? 650kbps seems like the max for an N based wifi network. Or at least what I tend to get on Hospital wifi. At the 2015 txlf we had AC wireless and I got 1210kbps +/-, although ONLY after vendors had closed up and most users left. AKA during the lightning talks. Plus I had learned to force association with the "closest" AP.

# iwconfig wlan0 ap <mac address>
# dhclient -4 -v wlan0

Plus the usual essid and channel stuff. For non encrypted connection types. Even though the capture portal required a password.
 
Old 01-23-2017, 04:52 PM   #7
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I'd log into the modem for the advanced results of how the modem sees the signal.


"
Could this low bandwidth be due to using an extension telephone line from the telephone wall socket to my modem-router which is about thirty feet long"


I assume you have some sort of DSL correct?? Yes, defects in the copper line to the home office will show up in a time domain reflectometer (TDR) usually. The service techs have a unit and should know how to use it. The wire and signal have to be correct at your modem for best results.


Generally you can reset the line by removing the outside connection to ISP and let stand for 24 hours and connect back and it is supposed to re-set values.

This isn't one of those bit and byte deals is it?

Last edited by jefro; 01-23-2017 at 08:38 PM.
 
Old 01-23-2017, 07:01 PM   #8
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Quote:
Originally Posted by grumpyskeptic View Post
I am using Linux Mint 17.3 Rosa Cinnamon.

The bandwidth I get when downloading big files is only about 650kbs, a fraction of the two or three mbps that the ISP apparently provides. I live in an urban area, so I ought to get a reasonable service.

Could this low bandwidth be due to using an extension telephone line from the telephone wall socket to my modem-router which is about thirty feet long?

If that is the problem then it would be a waste of time and money to e.g. buy a new modem-router.

Thanks
I am in the process of rebuilding my house after a big fire. I live in a rural area in Virginia and the phone company does not provide DSL support like they do in urban areas. The U.S. government has passed a law that in these circumstances the phone company has to allow small companies to provide DSL service using the phone company equipment.

I asked the phone company to install a line capable of supporting both voice service and DSL. They dug a trench and installed a line to a box on the side of my house. Then they ran an ordinary phone line into my house with about 20 feet of ordinary phone line inside the house. The phone worked fine.

I then bought DSL Internet service from Waterford Telephone Company which is a one man telephone company owned and operated by Bruce Davis. Bruce came to my house and replaced the ordinary phone line with a shielded cable phone line running to his DSL modem. He said that ordinary phone cable is too error prone to run DSL. He installed a splitter so that ordinary phone cable is running from the splitter to the phones. I installed a router and an old laptop computer. Everything works fine and the service is far superior to the best satellite dish service I had before the fire.

---------------------
Steve Stites
 
Old 01-24-2017, 05:04 AM   #9
grumpyskeptic
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Thanks. On reflection the plug-in telephone line extension is probably 50ft long rather than 30ft. It is just a very cheap thin wire.

The modem-router is quite old and is ADSL.

It does not do WiFi as I have no need for it, and I am concerned about the lack of security with wifi. As I am in a high-density urban setting living in what I believe is called a "row house" in American English and a "terraced house" in British English then my neighbours are less than 2ft from my modem and I would prefer not to have them observing my internet traffic, in the same way that I would prefer them not to listen to my telephone calls.

Here are the results from the online tests suggested by pan64:

freeola.com/line-test -

Packets lost: none
Latency: 43.783ms
Jitter: 2ms

speedtest.net -

Ping 59ms
Download speed 5.27 mbps
Upload speed 0.81 mbps

dslreports.com/pingtest -

"Radar plot disabled due to slow draw performance (53ms)"
Three text results, all "Grade A+"

Am I correct to think that the above indicates that neither my old modem-router nor the cheap telephone line extension is the problem, and that the low bandwidth is probably due to the ISP throttling down the bandwidth after a short while?

If it is, is the throttling due to any setting in the modem-router which I can alter?

Thanks.

Addendum:

Here are the results from smallpond's suggestion of trying the ifconfig command. I have deleted all the addr details.

$ ifconfig
eth0 Link encap:Ethernet HWaddr ----------
inet addr:--------- Bcast:----------- Mask:255.255.255.0
inet6 addr: ------------------ Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:43024 errors:0 dropped:0 overruns:0 frame:0
TX packets:38646 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:43954571 (43.9 MB) TX bytes:4738510 (4.7 MB)

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:684 errors:0 dropped:0 overruns:0 frame:0
TX packets:684 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:82354 (82.3 KB) TX bytes:82354 (82.3 KB)

In the past couple of days I have been fiddling with the modem-router settings without understanding what I am doing, so the above may reflect that.

jefro: "I'd log into the modem for the advanced results of how the modem sees the signal."

I have learnt how to log in to my modem-router but I do not know what of the many settings to look at or what they mean.

Last edited by grumpyskeptic; 01-24-2017 at 05:18 AM.
 
Old 01-24-2017, 05:51 AM   #10
pan64
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can you check the capabilities of your modem/router? can you post some info about them?
 
Old 01-24-2017, 06:40 AM   #11
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Quote:
Originally Posted by grumpyskeptic View Post
The bandwidth I get when downloading big files is only about 650kbs, a fraction of the two or three mbps that the ISP apparently provides. I live in an urban area, so I ought to get a reasonable service.

Could this low bandwidth be due to using an extension telephone line from the telephone wall socket to my modem-router which is about fifty feet long?
Nothing to do with any of that, it's your math.

650kb/s is approximately 5mb/s

EDIT: Sorry, MY math is faulty, for some reason I'd read your speed as 650KB/s rather than kbs. Ignore me, I'll go back to sleep!

Last edited by TenTenths; 01-24-2017 at 06:48 AM.
 
Old 01-24-2017, 12:17 PM   #12
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Quote:
Originally Posted by grumpyskeptic View Post

Am I correct to think that the above indicates that neither my old modem-router nor the cheap telephone line extension is the problem, and that the low bandwidth is probably due to the ISP throttling down the bandwidth after a short while?
If your Internet service is being provided by a TV cable company then the bandwidth available can vary widely from time to time. The cable company quotes you a speed based on only one customer using the cable. When additional customers get on the line the bandwidth is split among the active users. Here in the U.S. it is common for a TV cable modem to give dial-up Internet speeds when a cable is fully loaded with active customers. I am not sure that this problem occurs with all TV cable companies all the time but I know that it occurred often when TV cable companies first began offering Internet connections.

Other types of Internet providers sometimes try to keep a person from using large amounts of bandwidth for extended periods. They may put clauses in the contract which say that if you exceed certain limits then they will penalize you by cutting your speed for a set period of time. I had one satellite dish Internet provider who only allowed large downloads between midnight and 4:00 am. When I violated this restriction they cut my Internet speed to dial-up type speed for the rest of the calendar month. You should read your contract to see if you have run afoul of such restrictions.

----------------------
Steve Stites
 
Old 01-24-2017, 12:39 PM   #13
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Have you tried the usual tricks of changing your MTU setting?

# ifconfig eth0 mtu 1492

Carrier grade NAT and other things that can make the default 1500 a less than optimal setting. 576 was the old dialup value, and still works better in many cases. Minus multiples of 40 for each NAT layer (ipv4), and 60 for ipv6. The 1492 was a trick used with early cable providers that proved fruitful. Smaller packets have better queueing and feel more responsive (on slow connections). And being just a few bytes more than the actually provided MTU can send up to twice as many packets / headers. On noisy lines, smaller packets could overcome the need to repeat as many packets that were unsuccessful. Still just a minor work around for the larger issue of the service being provided. But something to try.
 
Old 01-24-2017, 04:22 PM   #14
ondoho
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many posts (many cooks...), but i haven't seen the most obvious suggestion:
temporarily use a much shorter phone cable and see if that improves network speed.
(and yes, i'm aware that that means moving the router and probably the computer, too, unless you have a spare laptop to hook up)
 
Old 01-24-2017, 07:02 PM   #15
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The copper line part of this story is usually up to 8000 feet or more in some cases. Every connection and wire could cause issues. While this 50 foot line could be bad, it is unlikely to be the problem based on it's length.

It won't hurt to try a new wire.

You have to go to web pages and see what the numbers mean on your modem. Most all modems have very advanced reporting tools to tell you what the provision is and what the signal is and such. Your answers are in there.
 
  


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