Slow download speeds on O2 20meg Ultimate

[phillai]

Since I joined O2 20meg Ultimate broadband (since Wed 12th Nov), I'm getting speeds slower than when I previously had my Sky 16mb Sky Broadband Max!
On my newsgroups on Sky BB, I was getting typically download speeds of 1600 KB/s but since I joined O2 broadband I'm getting speeds of anything from 500 KB/s to a maximum of 1300 KB/s.

I've been on the phone to O2 five times now and although the O2 customer service is second to none (unlike crappy Sky!), they can't find out why I'm getting slow speeds!

Anyone have any ideas why? I really am stuck.

Here are some other things you might need to know. I'm running the O2 router wirelessly but this is plugged directly next to the ADSL Nation face plate (as before when I had Sky), with no phone plugged in.
My computer reports the wireless connection as excellent (this is only 4m from the O2 router).

I'm approximately 579 metres from the exchange (straight line distance).

I'm using this phone line purely for internet use only.

According to my O2 router these are my upload and download speeds (as of 9pm Mon 24th Nov)...

Bandwidth (Up/Down) [kbps/kbps]: 1,408 / 17,471

These are my router stats...

--------------------------------------------------------------------------------

DSL Connection

Link Information


Uptime: 0 days, 1:00:13

DSL Type: G.992.5 annex A

Bandwidth (Up/Down) [kbps/kbps]: 1,408 / 17,471

Data Transferred (Sent/Received) [kB/kB]: 0.00 / 0.00

Output Power (Up/Down) [dBm]: 12.0 / 18.5

Line Attenuation (Up/Down) [dB]: 11.5 / 22.5

SN Margin (Up/Down) [dB]: 3.5 / 3.5

Vendor ID (Local/Remote): TMMB / BDCM

Loss of Framing (Local/Remote): 0 / 0

Loss of Signal (Local/Remote): 0 / 0

Loss of Power (Local/Remote): 0 / 0

Loss of Link (Remote): 0

Error Seconds (Local/Remote): 0 / 0

FEC Errors (Up/Down): 3 / 171,255

CRC Errors (Up/Down): 3 / 0

HEC Errors (Up/Down): 5 / 0

[Mike8]

Well I saw a glitch tonight around 21:11, Im on 14Mb and have sync at 16376 and usually have thruput of 13500 ish. I tried thinkbroadband :: The UK's largest independent Broadband / ADSL comparison & review website test and it was 4788/1081. Had a cup of tea and rebooted and its now bringing in the usual 13500ish. I have noticed glitches during some peak hours.

[Saturday]

There are several possible reasons for poor throughput compared to sync. In rough order of likelihood:

• overloaded test server (try the one on this site)
• poor wireless quality signal (try wired)
• incorrect TCP/IP settings (XP only, try TCPOptimizer)
• something using bandwidth (other user on LAN, P2p running, malware)
• network congestion

From your description, my first bet would be a wireless issue. Frankly you can ignore what the adaptor reports as this is just wireless signal strength and it is wireless signal quality that matters. It is quite possible to have the router right next to the PC and still have a rubbish wireless quality signal - it's down to wireless interference.

First off try wired to verify this is the problem. If it is then experiment with different wireless channels starting at C13. You'd be amazed the difference this can make sometimes.

If it's not wireless then work your way down the list. It could of course be more than one thing.

BTW, your noise margins are rather low. Are you on a 3db profile? Low noise margin can impact throughput on anything other than a great line but I don't think that would account for the shortfall you're seeing. Your CRC are low (even though that's only a short period covered) so I don't think it's a line issue.

HTH

[phillai]

Saturday, thank you for your reply.

Sorry for sounding like a newbie but can you tell me what you mean by overloaded test server (try the one on this site)?

As for wired, yes I tried that and it seems the same.

Oh, I'm quite interested in changing the channels on wireless though - But I can't see an option to do this in the router!

As for incorrect TCP/IP settings, I did try TCPOptimizer but I gather I shouldn't be using this, as I'm using Vista 64bit, right?

Nothing else is using the bandwidth from what I see. I'm getting slow speeds from the off and it's on a freshly formated PC.

Also, what do you mean by my noise margins are low? How do I make it higher or correct? And I don't know what you mean by a 3db profile!

[Saturday]

The list I gave was a bit generic as I thought it might be useful for other people reading the forum. Most people measure their speed (throughput) using speedtest sites. The problem with most of these is that they aren't too good at coping with high speed connections and multiple users at the same time (the bandwidth costs can be huge for a free service to bear). So, at busy times the apparent speed people are getting seems low when in fact all that is being measured is the load on the server not the connection. In your case you quoted newsgroup speed but the same principle applies. Busy times equals slow speeds - again this can be the server not the connection.

If wired is the same then you've eliminated wireless as the issue. As I said earlier this is the most common reason but apparently not your problem.

Yes, TCPOptimizer is for XP only. Vista shouldn't need adjustment. In fact there's no easy way to do it even if you wanted to and using TCPOptimizer is likely to give problems, hence why I said XP only in the list.

If you've eliminated everything else then it looks like a network congestion problem.

Lastly, your router will normally have a default noise margin on boot up with O2 of 6db. You can ask for this to be changed, typically to 3db or 9db. If yours is the standard 6db then your noise margin has dropped to 3db which is a big fall for an O2 connection. This could signify a line noise problem.

My recommendation would be to call O2 and ask to be moved to 9db and see if that helps things (your router sync will drop a meg or so as a consequence). Or, you could try rebooting the router when the noise margin is low and you should find it resync at 6db and doesn't drop much below that.

If your router when rebooted syncs immediately at 3db then it looks like you're on a 3db profile for some reason.

[Saturday]

One other thing: have you had your text yet from O2 to say your line testing is finished? As you're only 12 days in you could still be under DLM.

[phillai]

Originally Posted by Saturday

Lastly, your router will normally have a default noise margin on boot up with O2 of 6db. You can ask for this to be changed, typically to 3db or 9db. If yours is the standard 6db then your noise margin has dropped to 3db which is a big fall for an O2 connection. This could signify a line noise problem.

My recommendation would be to call O2 and ask to be moved to 9db and see if that helps things (your router sync will drop a meg or so as a consequence). Or, you could try rebooting the router when the noise margin is low and you should find it resync at 6db and doesn't drop much below that.

If your router when rebooted syncs immediately at 3db then it looks like you're on a 3db profile for some reason.

I think I'm stuck on 3db - What should I change this to get faster download speeds?

Also, I've not had a text from O2 as yet to say that my line is finished...

P.S. I think I have some kind of success with the channel changing, it's not going up and down like a yo yo in my download speeds. I just need to keep playing around and see which channel is best. At best it's 1400 KB/s but it still don't beat my speeds on my old Sky Broadband...
Mind you, I have just realised that I had my previous broadband using Sky's DG834GT and I also am using the official Netgear WPN311 RangeMax wireless PCI Adapter which according to their website offers 'Up to 10x faster coverage and speed compared to 802.11g'.

Maybe I should try my old Sky DG834GT router again, perhaps?

[Mike8]

Regarding my reporting my glitch (scroll up), I agree it was probably everyone attacking the server at once. Not been able to reproduce it. I was on wired to the router within 3ft of the computer and router is currently going directly into the service connector of the NTE5 (extension off until I get a faceplate).
I now tend to use my old favourite speed test thinkbroadband which seems the most accurate and gives bar charts with the option to save in a profile, rather than the meter ones that zip up and down fairly fast. tbb site have checked their methods up to Gigs (see their video). But I think it must be bourne in mind that these tests are falable and really should be used for comparisons, i.e. look at any change in a number of readings. Now my line has been capped at 16M for my package I am sync'ed at 16376 and my thruput is usually around 13338 +/- 30. Anyway I think Im pretty happy with it.

[Saturday]

Originally Posted by phillai

I think I'm stuck on 3db - What should I change this to get faster download speeds?

If you've not had a text/email from O2 yet then there's every chance you're still in DLM. It can last for up to 15 days from first connection. Don't contact O2 about the 3db issue for now as it may resolve itself.

Yes, finding the best wireless channel can be a bit hit and miss. What you must do is find the channel that is furthest away from any interference. The high channels are least affected by extraneous interference from things like phones and microwave ovens but you also have to consider other wifi devices in the neighbourhood. With wifi devices getting more and more powerful, even neighbours some distance away can impact you. Wireless just isn't a reliable medium for high speed broadband in domestic situations. Don't believe the hype of the wireless device manufacturers. Although some people have an excellent wireless connection, they're in the minority. To get a high speed, stable connection requires both the router and adaptor the be 100% compatible and use the same type of technology e.g. both "n", Rangemax etc. Ethernet is way and above the best way to connect, followed by powerline adaptors if running wires is a problem.

The DG834GT is a pretty good router and its Broadcom chipset is a good match for O2/Be's DSLAMs.

[Mike8]

I agree, and if at all possible, I consider the main computer in the home or office should be wired. Its quicker, should be interference free, and does not need encryption to slow it. Encryption or not I wouldn't access online banking using wi-fi

ADSL2+ is a lot more sensitive, for example due to the frequency change, my s/n margin with adsl max (PPPoA)of 23dB came down to 6.8dB with adsl2+ on LLU PPPoE.

My personal feeling is to confine wi-fi to laptops!