QAM change

[slowcoach]

My IP address changed in the early hours of Monday, on checking the config file it now states that I am on QAM256 whereas previously it was QAM64, what difference, if any, will this make.

[Welshchris]

http://en.wikipedia.org/wiki/Quadrature_amplitude_modulation

This will explain

[Milambar]

He asked what difference it'd make, answer: None to you as a consumer, really, I dont think.

[Ignitionnet]

My IP address changed in the early hours of Monday, on checking the config file it now states that I am on QAM256 whereas previously it was QAM64, what difference, if any, will this make.

Absolutely none whatsoever.

[slowcoach]

Thanks guys.

[broadbandking]

Absolutely none whatsoever.

Won't it help with higher speed but can be a bit more unstable?

[BBKing]

You might have been shifted to a different UBR, particularly if you're on 20Mb. Happened to me a couple of weeks ago. The idea is to give us lots of lovely bandwidth to play in. I've got QAM256 down and QAM16 up, which is as good as it gets currently.

[Ignitionnet]

Won't it help with higher speed but can be a bit more unstable?

Something like that but so long as there are no congestion issues and the network is being kept in good shape all should be fine so practical impact to customer is zero.

---------- Post added at 10:28 ---------- Previous post was at 10:25 ----------

You might have been shifted to a different UBR, particularly if you're on 20Mb. Happened to me a couple of weeks ago. The idea is to give us lots of lovely bandwidth to play in. I've got QAM256 down and QAM16 up, which is as good as it gets currently.

I'm so looking forwarding to being moved considering they struggle to keep QPSK stable on a 1,000 home MAC domain here. Should be interesting when that becomes 4,000+ on the overlay build.

Quick note for other peeps, upstreams do go up to 64QAM and 128QAM but not on VM's network yet.

---------- Post added at 10:30 ---------- Previous post was at 10:28 ----------

Thanks guys.

Pleasure, I see you are listed on your info as being 20Mbit soon to be 50. You might remember the stuff about how when the 50Mbit service was about ready 20Mbit customers would be moved to that equipment to ease the load on the older equpment, that's probably what has happened here.

[Turkey Machine]

@broadbandings: What's required to get the upstream to move from QPSK to something a little higher like QAM16 or QAM64? I get great signal and power readings here in Nottingham, so why don't they do it?

[Ignitionnet]

@broadbandings: What's required to get the upstream to move from QPSK to something a little higher like QAM16 or QAM64? I get great signal and power readings here in Nottingham, so why don't they do it?

The load on the upstream doesn't justify it due to VM being tighter with upstream rates than an obsessive compulsive carrier pigeon, and I doubt you can see your upstream SNR ;)

[Turkey Machine]

The load on the upstream doesn't justify it due to VM being tighter with upstream rates than an obsessive compulsive carrier pigeon, and I doubt you can see your upstream SNR ;)

No I can't see my upstream SNR ;), but if I know my physics, the higher and cleaner/more stable the power rating, the better the SNR's likely to be. So it's just VM being tight b****rds then. Cheers, all I needed to know. :)

[Zhadnost]

Of course there is the vague possibility that upstream utilisation is quite low and upgrading it to QAM16 would cause a lot of faults for people who don't have such a good signal, would be a reasonable amount of work and would yeild bugger-all benefit.

[Turkey Machine]

Unless I'm mistaken, the nearest exchange to me is the Basford one in Nottingham. I'm 500m from it as the crow flies, about 650m on the road. There's what I think is a green VM cab just around the corner from me. Correct me if I'm completely wrong, but I'm confident they're capable of adjusting it street by street. Yes, if they did it across the board, it would probably cause more problems than benefits.

[Zhadnost]

I for some reason assumed it would need to be done upstream channel by upstream channel.

[Ignitionnet]

Correct me if I'm completely wrong, but I'm confident they're capable of adjusting it street by street. Yes, if they did it across the board, it would probably cause more problems than benefits.

Power levels yes, modulations no, this is done at the uBR / CMTS in Basford in your case.

---------- Post added at 18:50 ---------- Previous post was at 18:44 ----------

Of course there is the vague possibility that upstream utilisation is quite low and upgrading it to QAM16 would cause a lot of faults for people who don't have such a good signal, would be a reasonable amount of work and would yeild bugger-all benefit.

Indeedy. VM offer low upstream which tends to keep the utilisation relatively low compared to downstream.

[slowcoach]

You might have been shifted to a different UBR, particularly if you're on 20Mb. Happened to me a couple of weeks ago. The idea is to give us lots of lovely bandwidth to play in. I've got QAM256 down and QAM16 up, which is as good as it gets currently.
Looks like it, my reverse DNS now ends virginmedia.com, previously it was ntl.com.
Only one problem, I can no longer ftp into my VM space, I can http into it so it looks like an owner problem. I will get some Aspirin in and give myself a week off then start making the calls. :rolleyes:

---------- Post added at 21:45 ---------- Previous post was at 21:34 ----------


Pleasure, I see you are listed on your info as being 20Mbit soon to be 50. You might remember the stuff about how when the 50Mbit service was about ready 20Mbit customers would be moved to that equipment to ease the load on the older equpment, that's probably what has happened here.
Yes, more than likely.
I am in no hurry to upgrade until the upload speed is increased, download is currently 19Mb/s so it's pretty good on that score, that and the router would just be a paperweight as I am wired and have a router capable of 50Mb/s already.

[Ignitionnet]

Yes, more than likely.
I am in no hurry to upgrade until the upload speed is increased, download is currently 19Mb/s so it's pretty good on that score, that and the router would just be a paperweight as I am wired and have a router capable of 50Mb/s already.

Me neither actually sir, not least of which because I don't expect to be in the UK by Christmas, even if I were I'd struggle to justify the product as it is now. 53 / 1.75 is pants.

[Zhadnost]

It's still more than twice the download and more than twice the upload of the 20Mbit package.

I wonder if business customers will be offered a 50/2 package.

[Ignitionnet]

It's still more than twice the download and more than twice the upload of the 20Mbit package.

I wonder if business customers will be offered a 50/2 package.

The major reason a lot of people seem to be getting it is to enjoy not having STM and download a rather sweet amount of content. I rarely trip STM and don't download that much so it's kinda pointless for me. My only use for it would be if it had a much higher upload, not for the ratio to actually get worse.

I'm spoiled I guess, before I moved for 2 years I had over 2Mbit upload and could fire files out at 240kB/s - weird how you miss it believe me.

As the bandwidths go higher the returns diminish to be honest, 20Mbit -> 50Mbit, for me personally isn't any great shakes, 768k -> 1.75Mbit a slight improvement but still not really worth the contract which I won't finish anyway.

[slowcoach]

After taking the aspirins I took the plunge and called TS to get my web space access sorted, three calls later and a password change still not able to login via FTP, I can browse the site :dozey: so it is still there so if any VM associate can lend a hand I would be most appreciative. ;)