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volatile
06-01-2006, 22:25
Are these exceptable values for 10mb using a Surfboard sb4100, im getting some bad dl speeds etc just like some of the other peeps on this forum.

Downstream:
Frequency: 331000000 Hz Locked

Signal to Noise Ratio: 36 dB

QAM: 256

Network Access Control Object ON Power Level: 6 dBmV

Upstream:

Channel ID: 3

Frequency: 25500000 Hz

Ranged Ranging: Service ID 1011

Symbol Rate: 1.280 Msym/s

Power Level: 42 dBmV
quadplay
06-01-2006, 23:15
They're within DOCSIS specifications... but I don't know a lot about Telewest's network, so I couldn't say whether they are the root of your issue.

Have you contacted Telewest about your poor download speeds?
sollp
06-01-2006, 23:35
Are these exceptable values for 10mb using a Surfboard sb4100, im getting some bad dl speeds etc just like some of the other peeps on this forum.

Downstream:
Frequency: 331000000 Hz Locked

Signal to Noise Ratio: 36 dB

QAM: 256

Network Access Control Object ON Power Level: 6 dBmV

Upstream:

Channel ID: 3

Frequency: 25500000 Hz

Ranged Ranging: Service ID 1011

Symbol Rate: 1.280 Msym/s

Power Level: 42 dBmV
Does Telewest use 256 QAM for the modem service, anyone work for Telewest confirm this or know if this is correct, i would have thought it would be 64 QAM. Or is the Telewest network 256 QAM?
volatile
06-01-2006, 23:50
Yes i have phoned them 3times this week already and every time it's the same answer/suggestion

"Do you have spyware? Do you have a virus? Not all spyware can be detected etc etc etc"

I scan everyday on a schedule and it finds cookie trackers that iare harmless. When i was on the 4mb i was dl always and above 450kb/sec but since being upgraded "upto" 10mb i barley get 250kb/sec most days. The only time i get max 10mb speed is in the late early hours of the morning.
Ignition
07-01-2006, 11:14
Does Telewest use 256 QAM for the modem service, anyone work for Telewest confirm this or know if this is correct, i would have thought it would be 64 QAM. Or is the Telewest network 256 QAM?

ntl and Telewest both use 256QAM where they can.

Sounds like congestion again. I'd speculate upstream congestion too due to this:

Symbol Rate: 1.280 Msym/s

Standard now is 2.56 Msym/s so unless Telewest are using 16QAM which seems unlikely as there's really not much point in a small channel with 16QAM they are going to have a lot of asymettry between upstream and downstream.

I'm actually starting to get an idea that Telewest cut a few corners here and there with their network so that while it gave the appearance of being marvellous once they started to push it and actually were in a position where they had to do big bandwidth upgrades they've found themselves with issues.

I can't say I'm completely amazed by issues in this case, this card has 38Mbit of downstream bandwidth but less than 14Mbit of of upstream available, with only 10Mbit or so of that usable before issues become apparent. With the usage of P2P, servers, etc, that the uncapped service encourages by being 100% uncapped not that much of a surprise that a user on an upstream where only 1.7Mbit or so is available without congestion (5 users of 4M or 10M) is seeing probs.

Making sense too why TW didn't increase the upstreams if the above isn't an uncommon situation. Banging in uBRs is all well and good but if you don't upgrade the RF to allow a higher split (allow more upstream) it's a pointless exercise.
volatile
07-01-2006, 12:05
What you suggest i should do Ignition? Put up with it or what?
Ignition
07-01-2006, 16:41
What you suggest i should do Ignition? Put up with it or what?

Ask Telewest if there's upstream congestion in your area, and if there is if they can move you to a less congested upstream.
KenK2
10-01-2006, 19:07
Ignition,

Just for clarity, with reference to volatile's post, would changing the upstream channel in the modem configuration help and resolve the issue?
sollp
10-01-2006, 22:27
Ignition,

Just for clarity, with reference to volatile's post, would changing the upstream channel in the modem configuration help and resolve the issue?

You can't change the upstream frequency.
Ignition
10-01-2006, 23:48
You can't change the upstream frequency.

You can change the channel on the Motorola Surfboards.
volatile
11-01-2006, 21:56
OK, i phoned TW and they switched me to a less busy UBR and iv'e been getting more that 10mb on most fo my dl's the past few days so i guess that's good on my behalf.
Ignition
14-01-2006, 23:53
OK, i phoned TW and they switched me to a less busy UBR and iv'e been getting more that 10mb on most fo my dl's the past few days so i guess that's good on my behalf.

Less busy upstream channel :)

If you have a Motorola Surfboard you can also do this yourself should you wish to.

I guessed right obviously, although with Telewest at the moment that's not very difficult sadly as nearly all of their probs seem to be this.
jtwn
14-01-2006, 23:58
I do believe however on ntl this isn't the case, it just defaults back to the original frequency when you 'save' it.
Ignition
15-01-2006, 00:02
I do believe however on ntl this isn't the case, it just defaults back to the original frequency when you 'save' it.

Nope shoudn't really matter. I can't remember when I was there there being anything that would enforce the original upstream on modems.
sollp
15-01-2006, 21:37
Less busy upstream channel :)

If you have a Motorola Surfboard you can also do this yourself should you wish to.

I guessed right obviously, although with Telewest at the moment that's not very difficult sadly as nearly all of their probs seem to be this.

Ok so what upstream would you know to change it to?
jtwn
16-01-2006, 21:12
From clientside you used to be able to check the utilisation of channels through Robin Walker's DOCSDIAG, but now, at least with ntl, they have disabled SNMP and you can't use it anymore.