ADSL Sync Speeds

[kalevra]

Hi all...

Our company originally had our ADSL installed and had a line speed of 4Mbps - this was stable for some time (a few months)... The strange thing is that every 2 months (or so) I would get frequent sync issues and have to phone Telkom to ask for a lower sync speed - we are currently on 1Mbps

The line is more or less stable although it does resync or unsycn and sync again at least 3/4 times a day which is, for the most part manageable.

We had a telkom technician in a while ago and he has told me we are 4km from the exchange this is the best speed we can hope to achieve - but surely this makes no sense seeing as though the line was stable and syncing at 4Mbps in the first place for more than 1 month???

My current ADSL stats:

Downstream Upstream
SNR Margin 16.5 dB 15.5 dB
Line Attenuation 48.0 dB 31.0 dB
CRC Errors 0 0
Latency Fast Fast

Previous stats (February 2011)

My stats:
SNR Margin 16.5 dB 13.0 dB
Line Attenuation 49.0 dB 32.0 dB
First number downstream - second number up stream.

Any ideas???

 

[Spyk3r]

Your line stats seem better than mine when I was on 4mbps... You shouldn't be having problems connecting. What have you tried to remedy the situation?

 

[kalevra]

Your line stats seem better than mine when I was on 4mbps... You shouldn't be having problems connecting. What have you tried to remedy the situation?

I've tried getting Telkom to up the line speed ... in that state it won't even sync at all... We evetually called a technician out who tested the line and said there was nothing he could really do and that I'm lucky to have even the 1Mbps

 

[russellO]

My stupid TrendNet TEW-635BRMv2 modem can't even display SNR and Attenuation details. That's probably why it was only R600.

But anyway, if I remember correctly, I saw a post here somewhere where some clever MyBB guys said anything under 20dB for SNR is very good.

 

[Pada]

My office in Techno Park, Stellenbosch, had exactly the same.

We first had a stable 4Mbps connection for the first 6 months or so. Then it became unstable, so we downgraded to 2Mbps, and a month or so later we had to downgrade to 1Mbps. When we struck 1Mbps, we actually swapped our Cisco ADSL modem for a D-Link ADSL modem and then we were able to get like 3Mbps fairly stable again.
Besides the poor SNR margins that we had, our latencies during office hours was shocking. It ranged between 1 - 3 seconds!
Eventually we got moved to a newly constructed DSLAM, which was closer by, and then all our problems was sorted out.

Your SNR margins looks fine for a stable 4Mbps.

I would suggest that you try to get hold of a Telkom technician during the times that your line is experiencing problems, otherwise he might never find the problem.

 

[russellO]

I've tried getting Telkom to up the line speed ... in that state it won't even sync at all... We evetually called a technician out who tested the line and said there was nothing he could really do and that I'm lucky to have even the 12Mbps

That just sounds odd to me. 4Km isn't that far. I am on the outskirts of PE with a 10mb line and a friend is like 6km out of the suburbs on a smallholding and a 4mb line with no problems.

But then again I'm not a technician. He would know better than me (if he is qualified and not posser).

 

[Pada]

My stupid TrendNet TEW-635BRMv2 modem can't even display SNR and Attenuation details. That's probably why it was only R600.

But anyway, if I remember correctly, I saw a post here somewhere where some clever MyBB guys said anything under 20dB for SNR is very good.

R600 isn't cheap for an ADSL modem either.
The ADSL modems that I recommend are the D-Link DSL-2500U (1x 100Mbps LAN, no WiFi), which goes for under R200, and the TP-Link W8960N (4x 100Mbps LAN + Wireless N) which goes for around R650.

And it's not SNR margins under 20dB that is good, but rather SNR margins above 12dB that is good.

@kalevra:
I hope you meant 2Mbps and not 12Mbps, because on 4km range you're pretty much stuck on 4Mbps and lower, depending on the ADSL modem's quality.

 

[kalevra]

My stupid TrendNet TEW-635BRMv2 modem can't even display SNR and Attenuation details. That's probably why it was only R600.

But anyway, if I remember correctly, I saw a post here somewhere where some clever MyBB guys said anything under 20dB for SNR is very good.

And line attenuation... ? Is mine not a bit high?

 

[kalevra]

R600 isn't cheap for an ADSL modem either.
The ADSL modems that I recommend are the D-Link DSL-2500U (1x 100Mbps LAN, no WiFi), which goes for under R200, and the TP-Link W8960N (4x 100Mbps LAN + Wireless N) which goes for around R650.

And it's not SNR margins under 20dB that is good, but rather SNR margins above 12dB that is good.

@kalevra:
I hope you meant 2Mbps and not 12Mbps, because on 4km range you're pretty much stuck on 4Mbps and lower, depending on the ADSL modem's quality.

Sorry yes - I meant 1Mbps not 12Mbps...

 

[K@kkArlak]

R600 isn't cheap for an ADSL modem either.
The ADSL modems that I recommend are the D-Link DSL-2500U (1x 100Mbps LAN, no WiFi), which goes for under R200, and the TP-Link W8960N (4x 100Mbps LAN + Wireless N) which goes for around R650.

And it's not SNR margins under 20dB that is good, but rather SNR margins above 12dB that is good.

@kalevra:
I hope you meant 2Mbps and not 12Mbps, because on 4km range you're pretty much stuck on 4Mbps and lower, depending on the ADSL modem's quality.

Yeah, I'd also recommend the 2500U, best for a small househould where connectivity is all you need. For wireless b/g get the 2540U, and for b/g/n the 2740U. I've had each of these 3 for about 3 years now in 3 different places, and the only one that doesn't work anymore was due to lightning.

 

[kalevra]

Yeah, I'd also recommend the 2500U, best for a small househould where connectivity is all you need. For wireless b/g get the 2540U, and for b/g/n the 2740U. I've had each of these 3 for about 3 years now in 3 different places, and the only one that doesn't work anymore was due to lightning.

Do you think a different router could solve connectivity problems?? Does a better modem enhance SNR/ Attenuation etc? I'ev got the Mega 200VWR (Billion I think)

 

[Pada]

I highly doubt that you'll get a noticeable SNR margin increase with a better ADSL modem.

Your SNR margins are already good enough to maintain a stable ADSL connection, so there is definitely something wrong with your line which causes connection problems.

 

[kalevra]

So if my line stats are good and can sustain a better connection. Also even at my low sync speed of 1Mbps that I'm still having frequent disconnects during the day - what is the best way forward in getting the write technician to come out and fix the situation so I can have at least 2 - 4 Mbps???

Any ideas, or if you've had a similar personal experience.

Thanks in advance!