Advice needed regarding ADSL line issues

ponder

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I have a 1mbps line and I used to get like 1.01mbps/1.02mbps on Speedtest.net, recently it has gone down to between 0.70mbps and 0.80mbps max.

Physically impossible! Either the speed test results were wrong or you are 'mistaken'.

The highest speed you can attain on a 1Mb/s line is about 0.85Mb/s or 109KB/s

0.80Mb/s (102KB/s) is still a pretty good speed, that's what I normally average on.

It's a best effort service, hence the claims of up to 1Mb/s.
 
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p13t

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Sep 8, 2012
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Physically impossible! Either the speed test results were wrong or you are 'mistaken'.

The highest speed you can attain on a 1Mb/s line is about 0.85Mb/s or 109KB/s

0.80Mb/s (102KB/s) is still a pretty good speed, that's what I normally average on.

It's a best effort service, hence the claims of up to 1Mb/s.

Isn't it that the highest speed possible is 1024/8=128KB/s=1MB/s? I know this is never the case, but if you have like a 2MB/s line with a 1MB/s account you could get that maybe? I think this was sort of the case because I actually had the technician over now and he suggested that what happened was that with the new Telkom speed reshuffles they saw that the profile at exchange was giving the line a higher speed than it should get so they recreated the profile and that's why it has gone down. His words not mine. So either way will have to wait for the Telkom upgrades or just get a 2MB/s line now and wait for the price drops, if they come...
 

ponder

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Isn't it that the highest speed possible is 1024/8=128KB/s=1MB/s?

NO. You have TCP/IP & ATM protocol overheads on you line which can account for up to 16% of your bandwidth. It's not something you can get away from, without the protocols the data would never leave your PC.

http://en.wikipedia.org/wiki/Point-to-point_protocol_over_Ethernet#Protocol_overhead
https://www.google.co.za/url?sa=t&r...=Appf81kLdQulOKy00ZckuQ&bvm=bv.53371865,d.Yms
https://www.google.co.za/url?sa=t&r...=3kT_pt3LK1ESHJqzWmAXkA&bvm=bv.53371865,d.ZGU
www.iol.unh.edu/services/testing/dsl/knowledgebase/ADSL_Tutorial.pdf
 
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elievan

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Mar 20, 2010
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Ponder, you seem sharp on this stuff. Do you have any idea what could e causing my problem? Good ping, good upload speeds, almost zero on the download side
 

ponder

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Ponder, you seem sharp on this stuff. Do you have any idea what could e causing my problem? Good ping, good upload speeds, almost zero on the download side

No problem, we can try this tomorrow. Please PM if I have not replied again by 18:00 as it means I have forgotten, I'm getting old.
 

ponder

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Ponder, you seem sharp on this stuff. Do you have any idea what could e causing my problem? Good ping, good upload speeds, almost zero on the download side

0. What echange are you connected to, first 6 digits of phone number and name.
1. What is your line speed?
2. Who is your ISP and what package do you have with them? What is you current usage for the last 10 days and are you possibly throttled?
3. From your routers web interface post your line stats wrt to SNR, attenuation & ATM status.
4. Do a speedtest to your closest server and post the results http://capetown.spdtst.saix.net/
5. ping & traceroute telkom.co.za and post the results here.
6. Download the first 30-50MB of ftp://ftp.saix.net/pub/linux/distri...9/Live/i386/Fedora-Live-Desktop-i686-19-1.iso with a decent download manager and tell us what speeds you average.

Wrt 6 above:
http://portableapps.com/apps/internet/wxdownload_fast_portable is a small portable multithreaded download manager you can try, set it to 1 thread and see what you get and then set it to 10 threads and see what you get. You can also try wget for windows or visualwget if the command line is not your cup of tea.

Post the info from the above and we can take it from there.
 
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elievan

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Mar 20, 2010
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Thanks Ponder, I'll spend the evening doing all of this and post it all at once!

Appreciate your help with this
 

elievan

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EDIT 3: My last 20 or whatever speedtests over a month: http://www.speedtest.net/results.php?sh=1145b2f061b546865da89e922da960fe&ria=0

EDIT4: I also want to add I get the same problem/speeds on my wired desktop, wired and wireless laptop, and on my phone!

0. What echange are you connected to, first 6 digits of phone number and name. sorry I don't know which exchange? Its in Rosebank tho, first 6 digits are 327 398 of the line

1. What is your line speed? 2mb/s line

2. Who is your ISP and what package do you have with them? What is you current usage for the last 10 days and are you possibly throttled? I have a few accounts, a capped and uncapped account with axxess, an uncapped account with openweb, and a 1G trial account with afrihost. All giving me the same issue! The results below are with the openweb account. 100% not capped on any of em since I can't use em at all for the last month.

3. From your routers web interface post your line stats wrt to SNR, attenuation & ATM status. Connected at 2048 down, 512 up. Max speed it says i can get is 12016 down and 1152 up. noise margin 31.8/13. attenuation 6/1.5. (What is ATM?)


4. Do a speedtest to your closest server and post the results http://capetown.spdtst.saix.net/
You'll think i'm nuts, but I cant run a speed test on that link. It pings, and i have a good low +-30ms ping, then the download part just sits there and never connects. I've tried it on the speedtest.net site, and once in awhile the download will actually begin, when it does its speed is about 0.15 to 0.30, if the download actually happens then upload speed is always fine at 0.45.

EDIT: after couple minutes it shows 0.26mb/s downloading, but its stuck there and not moving

EDIT2: it finished, says 34ms ping, 0.26 down, 0.45up



5. ping & traceroute telkom.co.za and post the results here.
Tracing route to telkom.co.za [196.43.22.222]
over a maximum of 30 hops:


1 <1 ms <1 ms <1 ms dsldevice.lan [192.168.10.1]
2 42 ms 23 ms 16 ms 196-210-138-129.dynamic.isadsl.co.za [196.210.138.129]
3 34 ms 46 ms 55 ms 196.38.72.229
4 55 ms 55 ms * cdsl2-rba-vl150.ip.isnet.net [196.38.73.9]
5 42 ms 56 ms * 196.26.0.61
6 56 ms 76 ms 54 ms 196.26.0.130
7 * 32 ms 21 ms rrba-ip-se-2-wan.telkom-ipnet.co.za [196.25.46.89]
8 52 ms * 23 ms 196.43.25.137
9 59 ms 72 ms 55 ms 196.43.39.162
10 25 ms 27 ms 19 ms rrba-ip-bssr-1-ge-2-48.telkom-ipnet.co.za [196.43.23.6]
11 * * 55 ms nbsc-ip-bssr-1-atm-5-0-0-1.telkom-ipnet.co.za [196.43.23.30]
12 19 ms 35 ms 41 ms *nbsc-ip-rcache-1-vif0.telkom-ipnet.co.za [196.43.22.222]




Trace complete.
6. Download the first 30-50MB of ftp://ftp.saix.net/pub/linux/distri...9/Live/i386/Fedora-Live-Desktop-i686-19-1.iso with a decent download manager and tell us what speeds you average. In the 5 minutes I've been trying to download the download manager its successfully done 320KBs. It sometimes shows its downloading at 3.4kb/s but most of the time at 0. I tried downloading the FedoraLiveDesktop(?) thing without the download manager and its doing the same thing. Oh they both just failed 6 minutes in.

Wrt 6 above:
http://portableapps.com/apps/internet/wxdownload_fast_portable is a small portable multithreaded download manager you can try, set it to 1 thread and see what you get and then set it to 10 threads and see what you get. You can also try wget for windows or visualwget if the command line is not your cup of tea.

Post the info from the above and we can take it from there.[/QUOTE]
 
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ponder

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Ok, a few more things.

1. How many devices (pc/laptop) do you have and do you experience the same with all of them? If you only have one device try booting from a linux livecd and downloading from that, just to eliminate your OS.
2. Reset your router to factory defaults and then reconfigure it.
3. Try these dns servers 196.43.38.190, 168.210.2.2, 8.8.8.8, 208.67.222.222 one at a time.

At first glance all the info you provided does not seem to indicate any issue except for the low download speed. If the above three new points don't help then I would be at a genuine loss and suggest you PM TelkomZA with all the info you provided me and ask them to investigate, ask for a port reset for starters, ask him to check for backhaul congestion on your dslam (can it really be this bad?) and if there is congestion to find another dslam within rosebank exchange with less congestion and a free port they can move you to. When you PM Telkom ZA include your full phone number and include all the above info, might as well cc Ranger but he's out of country at the moment.

I found another poor sod with similarly poor speeds as yours http://mybroadband.co.za/vb/showthr...elp-needed?p=10950491&viewfull=1#post10950491
 
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