Why is ADSL speed so variable?

Foxhound5366

Foxhound5366

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Here's a typical speedtest graph for me:

interwebs.PNG

The accompanying speedtest results (not that they show anything new): http://www.speedtest.net/my-result/4056660555

So my big question is simply why is ADSL speed so variable? Does this purely have to do with Telkom (my ISP) dynamically changing my effective download speed every second based on the current user demand in the area (or off the same shared infrastructure at least)?

These days I hardly ever see about 2.5MB/s downloads on my 4Mbps uncapped line, and to add insult to injury it's not *just* that my speed is low, but that it fluctuates (between 2.0-3.0 MB/s as the graph above shows).
 
Congestion on any node in a network can affect the network. Plus, in addition to that, Telkom does shape content based on the load of the network, your usage, and your demand at certain times. You'll likely never see full speed unless between 00:00 and 06:00.
 
giggity said:
Congestion on any node in a network can affect the network. Plus, in addition to that, Telkom does shape content based on the load of the network, your usage, and your demand at certain times. You'll likely never see full speed unless between 00:00 and 06:00.
Click to expand...
That is really useless ... so basically the people who benefit from the best Internet speeds are the people who use it to download massive files using download managers overnight, hmm?

The worst part of this for me is that I'm a brand-new Telkom subscriber, and my 'usage' bar has never left the green side of their visual tracker. I have no 'bad' history which might justify my being throttled, and based on my router's line stats I've actually got a strong connection.

In this case, 'strong connection' means 'the buffering screen loads really quickly'.

*sighs* It's the 21st Century, and even a 4Mbps Telkom connection won't allow a single user to stream video without slamming into buffers every few seconds. Admittedly, there *are* a few rare occasions (over weekends) when things seem to improve, but week nights? Forget it.
 
Well the reason they get to benefit is because the network load is really low at that time.
Note that speed tests aren't necessarily a great representation of your internet speed. They can be incredibly inaccurate if there is a problem with their servers' speeds, and they can also be prioritized by your ISP to make the speeds look better. It works either way.

How are speeds with other downloads? Try download a linux distro (~1GB) and see what the speeds are whilst downloading. If it's still bad...

Try this:
1. Go to speedtest-rba.isdsl.net and report back the results.
2. Now, set up a PPPoE connection with the username guest@telkomadsl, password guest.
3. Then go to http://capetown.spdtst.saix.net/ and run all of the tests and report back. (you have to disconnect the guest account before being able to use anything other than telkom.co.za or saix.net).

If those speeds are fine, then the problem is due to Telkom Internet shaping/throttling (note that that isn't the same as Telkom. Your line is likely fine, but your ISP package isn't up to par.) Contact them and report the issue.

Another question, and I don't mean to insult, is: are you sure you are actually on a 4mbps package? If you have a 2mbps data package and a 4mbps line with Telkom, then those are about the speeds you could expect. Just a possibility :whistle:

Oh yeah, also, in response to your original post, it's mb -- not MB. There's a big difference (1mb = 1/8 MB) :)
 
Lol, thanks for the help ... that's quite a to-do list.

The 'Linux ISO' thing seems like a hit-and-miss ... just looking at the download speeds of a random one I found online, it's varying between 20KB/s all the way up to 50KB/s.

1: That Internet Solutions page returns the following results:
Start Time: 21:05:05
End time: 21:05:09
Download Size: 409600 bytes
Time Delta: 3.7253029346466 seconds
Download Speed: 107 KBytes/s [Is this why my life is so awful right now?]
Line Speed: 856 kbits/s

2: I've checked my line speed through my router, and it's reporting as follows:
Downstream Line Rate (Kbps): 4096
Upstream Line Rate (Kbps): 509
I actually honestly don't know where to check the speed of the data package (I haven't received my next statement yet). I'll sniff around Telkom's site, unless you know of some other alternative?
 
giggity said:
2. Now, set up a PPPoE connection with the username guest@telkomadsl, password guest.
3. Then go to http://capetown.spdtst.saix.net/ and run all of the tests and report back. (you have to disconnect the guest account before being able to use anything other than telkom.co.za or saix.net).
Click to expand...

Ok, finally managed to get that right (while forgetting and remembering my Telkom password along the way lol), and the results returned were a lot more healthy:

Download Speed: 3114 kbps (389.3 KB/sec transfer rate)
Upload Speed: 431 kbps (53.9 KB/sec transfer rate)
Latency: 20 ms

So giggity, what is your diagnosis? Do I need to phone Telkom and ask them if they've got my data package correct?

Or is this just life in SA, congestion and the ANC, etc etc?
 
Foxhound5366 said:
Lol, thanks for the help ... that's quite a to-do list.

The 'Linux ISO' thing seems like a hit-and-miss ... just looking at the download speeds of a random one I found online, it's varying between 20KB/s all the way up to 50KB/s.

1: That Internet Solutions page returns the following results:
Start Time: 21:05:05
End time: 21:05:09
Download Size: 409600 bytes
Time Delta: 3.7253029346466 seconds
Download Speed: 107 KBytes/s [Is this why my life is so awful right now?]
Line Speed: 856 kbits/s

2: I've checked my line speed through my router, and it's reporting as follows:
Downstream Line Rate (Kbps): 4096
Upstream Line Rate (Kbps): 509
I actually honestly don't know where to check the speed of the data package (I haven't received my next statement yet). I'll sniff around Telkom's site, unless you know of some other alternative?
Click to expand...

That definitely doesn't seem right.
Try this distro: http://www.ubuntu.com/download/desktop/thank-you?country=ZA&version=14.04.1&architecture=amd64 (I am getting ~475KiB/s on it).
Try that IS page a few more times. It can sometimes mess up (it's not 100% accurate -- just a very simple speed test).

Set up that guest account and do those SAIX speed tests. That will show you the true potential of your line (just to make sure your line isn't screwed).
In addition to this, try run a tracert to telkom.co.za and post the results back.
 
giggity said:
That definitely doesn't seem right.
Try this distro: http://www.ubuntu.com/download/desktop/thank-you?country=ZA&version=14.04.1&architecture=amd64 (I am getting ~475KiB/s on it).
Try that IS page a few more times. It can sometimes mess up (it's not 100% accurate -- just a very simple speed test).

Set up that guest account and do those SAIX speed tests. That will show you the true potential of your line (just to make sure your line isn't screwed).
In addition to this, try run a tracert to telkom.co.za and post the results back.
Click to expand...

Ok, so... Tracert results:


Tracing route to telkom.co.za [196.43.22.222]
over a maximum of 30 hops:

1 12 ms 1 ms 1 ms 10.0.0.2
2 11 ms 10 ms 11 ms wtvw-ip-bng-1.south.dsl.telkomsa.net [105.224.248.1]
3 17 ms 12 ms 14 ms ipc-4-up.south.dsl.telkomsa.net [105.226.0.30]
4 110 ms 13 ms 13 ms ipc-aggr-2.south.dsl.telkomsa.net [105.226.0.57]
5 109 ms 13 ms 12 ms 196.25.190.209
6 116 ms 37 ms 37 ms 196.43.39.166
7 94 ms 38 ms 36 ms rrba-ip-bssr-1-ge-2-48.telkom-ipnet.co.za [196.43.23.6]
8 77 ms 39 ms 39 ms nbsc-ip-bssr-1-atm-5-0-0-1.telkom-ipnet.co.za [196.43.23.30]
9 86 ms 39 ms 41 ms nbsc-ip-rcache-1-vif0.telkom-ipnet.co.za [196.43.22.222]

Trace complete.

Then I also tried that other Internet Solutions speed test again on my regular account:
Start Time: 21:34:52
End time: 21:34:54
Download Size: 409600 bytes
Time Delta: 2.1113839149475 seconds
Download Speed: 189 KBytes/s
Line Speed: 1512 kbits/s

And finally, your Linux ISO is averaging 40KB/s to 100KB/s.

Does any of that help the diagnosis?

PS: In case you missed it, I did try the guest account up above and posted the results.
 
Foxhound5366 said:
Ok, so... Tracert results:


Tracing route to telkom.co.za [196.43.22.222]
over a maximum of 30 hops:

1 12 ms 1 ms 1 ms 10.0.0.2
2 11 ms 10 ms 11 ms wtvw-ip-bng-1.south.dsl.telkomsa.net [105.224.248.1]
3 17 ms 12 ms 14 ms ipc-4-up.south.dsl.telkomsa.net [105.226.0.30]
4 110 ms 13 ms 13 ms ipc-aggr-2.south.dsl.telkomsa.net [105.226.0.57]
5 109 ms 13 ms 12 ms 196.25.190.209
6 116 ms 37 ms 37 ms 196.43.39.166
7 94 ms 38 ms 36 ms rrba-ip-bssr-1-ge-2-48.telkom-ipnet.co.za [196.43.23.6]
8 77 ms 39 ms 39 ms nbsc-ip-bssr-1-atm-5-0-0-1.telkom-ipnet.co.za [196.43.23.30]
9 86 ms 39 ms 41 ms nbsc-ip-rcache-1-vif0.telkom-ipnet.co.za [196.43.22.222]

Trace complete.

Then I also tried that other Internet Solutions speed test again on my regular account:
Start Time: 21:34:52
End time: 21:34:54
Download Size: 409600 bytes
Time Delta: 2.1113839149475 seconds
Download Speed: 189 KBytes/s
Line Speed: 1512 kbits/s

And finally, your Linux ISO is averaging 40KB/s to 100KB/s.

Does any of that help the diagnosis?

PS: In case you missed it, I did try the guest account up above and posted the results.
Click to expand...

Ah sorry I was typing whilst you posted :)
Your results there seem quite fine. No signs of exchange congestion and your speeds look fine-ish for the speed test. How much have you downloaded this month? It's very possible that you are being throttled quite a lot judging from those results. If you have downloaded less than your expected threshold, I strongly recommend you contact [email protected].
 
giggity said:
Ah sorry I was typing whilst you posted :)
How much have you downloaded this month? It's very possible that you are being throttled quite a lot judging from those results. If you have downloaded less than your expected threshold, I strongly recommend you contact [email protected].
Click to expand...
So far only downloaded a whopping total of ... 8GB, lol. Peanuts.

For what it was worth I did a complete router reset (what a pain it was finding the manual for my router with the default log-in details!). Didn't help, as expected.

I was swamped at work today, so holding on the phone tonight. Waited 42 minutes for somebody at the Technical Help side to pick up, but no dice. Decided maybe the sales guys were more awake, so tried phoning them ... 12 minutes of that 'Ding ding ding whoop' hold music later and counting.

I may just have to try the e-mail thing after all.
 
Foxhound5366 said:
So far only downloaded a whopping total of ... 8GB, lol. Peanuts.

For what it was worth I did a complete router reset (what a pain it was finding the manual for my router with the default log-in details!). Didn't help, as expected.

I was swamped at work today, so holding on the phone tonight. Waited 42 minutes for somebody at the Technical Help side to pick up, but no dice. Decided maybe the sales guys were more awake, so tried phoning them ... 12 minutes of that 'Ding ding ding whoop' hold music later and counting.

I may just have to try the e-mail thing after all.
Click to expand...

After 6pm or something there seems to be near no one serving customers, you have to try morning/ afternoon.
 
Well, that was a big waste of time. Get through to Telkom Technical Support on the phone, the guy asks me to turn my router off, then on again... and ends up saying that what he's done is reset my connection from the box, and 're-designed' my connection (you'd hope it means 'applied less shaping to you').

I say thanks, hang up, hop onto the nearest speed test ... whopping 2Mbps download speed, off my 4Mbps connection. Ironically I was receiving 1.65Mbps back when I was on a 2Mbps line, so I don't see this as measurable improvement.

So now I'm back to square one: is this a uncapped problem (too much shaping - need to move to a capped bundle); is this a line issue (I don't think so based on my router stats); or is this just a plain ol-fashioned Telkom issue?

I smell another thread coming, stay tuned.

EDIT: Ok, it's confirmed ... A poll reveals I really do have an issue
 
Last edited:
Did you ask the Telkom rep to make sure if you were on a 4mbps package?
It still seems like you are either running 2mbps on 4mbps or you have a softcapped package.
 
giggity said:
Did you ask the Telkom rep to make sure if you were on a 4mbps package?
It still seems like you are either running 2mbps on 4mbps or you have a softcapped package.
Click to expand...
Ding ding ding, you were correct giggity!!!

I am *very* happy to say that I finally got a response from Telkom, informing me that they've upgraded my Telkom data package from Home Uncapped Basic (2Mbps) to Home Uncapped Advance (4Mbps) ... no explanation over why this wasn't done automatically as part of my line speed upgrade order (which was part of a Telkom Simple package deal).

Regardless, it worked: http://www.speedtest.net/my-result/4068416585

Interestingly, based on my original question here, the download speed graph is also a LOT more consistent:
OLD: interwebs.PNG

NEW: Download Speed.PNG

Pretty fascinating actually, and well done on spotting that giggity and co.

Moral of the story: even if your ISP has confirmed that they've made a requested upgrade for you, always double-check that it's actually performing exactly as it should be.
 
Happened to me too when I upgraded from Telkom 50GB softcap to 10Mbps uncapped. They upgraded my account to do premium uncapped which is 4Mbps instead of do premium plus uncapped which is 10Mbps.

It is hard to check on this as there are no indication of your current package ANYWHERE. You rely on 10210 to check and confirm it for you.
 
cavedog said:
Happened to me too when I upgraded from Telkom 50GB softcap to 10Mbps uncapped. They upgraded my account to do premium uncapped which is 4Mbps instead of do premium plus uncapped which is 10Mbps.

It is hard to check on this as there are no indication of your current package ANYWHERE. You rely on 10210 to check and confirm it for you.
Click to expand...
Um, I think it actually tells you on your statement, but you only get that a month *after* you've done your upgrade. Not that useful.

The issue for me was that I phoned 10210 and spoke to one of their technicians at their ADSL fault reporting line, and he went through a long story of resetting and redesigning my connection, but didn't even notice that I was on the wrong data package for my line-speed. Surely that should be the very first diagnostic step?

My guess is it's not too clear for them either.
 
And all this supports my belief that there are too many packages and options on offer... (with Telkom). It confuses everybody, including themselves!!
 
cavedog said:
Happened to me too when I upgraded from Telkom 50GB softcap to 10Mbps uncapped. They upgraded my account to do premium uncapped which is 4Mbps instead of do premium plus uncapped which is 10Mbps.

It is hard to check on this as there are no indication of your current package ANYWHERE. You rely on 10210 to check and confirm it for you.
Click to expand...

When I upgraded my 4Mbps uncapped to 10Mbps they only upgraded the line and not the data so I still only got 4Mbps when I used Telkom. If I used my backup from another ISP I got the full ten.
 
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