Docsis 1.1 switch over supposed to improve overloaded UBR's?

[Broken Hope]

I was under the impression that when the 20Mb customers were switched over to Docsis 1.1 after their UBR's were upgraded to 50Mb that their situation would improve, well last night my UBR (Basford) was switched over, I have a new IP and my host name is now cpc1-basf8-2-0-custXXX12-3.cable.virginmedia.com indicating that it has indeed been upgraded and yet right now I'm getting the following speed test

Test 1: 1024K took 1569 ms = 652.6 KB/sec, approx 5377 Kbps, 5.25 Mbps
Test 2: 1024K took 1179 ms = 868.5 KB/sec, approx 7156 Kbps, 6.99 Mbps
Test 3: 1024K took 1305 ms = 784.7 KB/sec, approx 6466 Kbps, 6.31 Mbps
Test 4: 2048K took 2053 ms = 997.6 KB/sec, approx 8220 Kbps, 8.03 Mbps

Overall Average Speed = approx 6805 Kbps, 6.65 Mbps

Worse is now my already high upstream power is even worse since the change

Upstream Lock : Locked
Upstream Channel ID : 1
Upstream Frequency : 47400000 Hz
Upstream Modulation : QAM16
Upstream Symbol Rate : 2560 Ksym/sec
Upstream transmit Power Level : 61.0 dBmV
Upstream Mini-Slot Size : 2

Whilst my connection is currently stable and I'm not having issues with it dropping my download speeds is still no where near the 20Mb I'm paying for.

[monkey2468]

Upstream power level is much too high. You need a tech.

[Sirius]

I was under the impression that when the 20Mb customers were switched over to Docsis 1.1 after their UBR's were upgraded to 50Mb that their situation would improve, well last night my UBR (Basford) was switched over, I have a new IP and my host name is now cpc1-basf8-2-0-custXXX12-3.cable.virginmedia.com indicating that it has indeed been upgraded and yet right now I'm getting the following speed test

Test 1: 1024K took 1569 ms = 652.6 KB/sec, approx 5377 Kbps, 5.25 Mbps
Test 2: 1024K took 1179 ms = 868.5 KB/sec, approx 7156 Kbps, 6.99 Mbps
Test 3: 1024K took 1305 ms = 784.7 KB/sec, approx 6466 Kbps, 6.31 Mbps
Test 4: 2048K took 2053 ms = 997.6 KB/sec, approx 8220 Kbps, 8.03 Mbps

Overall Average Speed = approx 6805 Kbps, 6.65 Mbps

Worse is now my already high upstream power is even worse since the change

Upstream Lock : Locked
Upstream Channel ID : 1
Upstream Frequency : 47400000 Hz
Upstream Modulation : QAM16
Upstream Symbol Rate : 2560 Ksym/sec
Upstream transmit Power Level : 61.0 dBmV
Upstream Mini-Slot Size : 2

Whilst my connection is currently stable and I'm not having issues with it dropping my download speeds is still no where near the 20Mb I'm paying for.

Nothing to do with the UBR

[Broken Hope]

Nothing to do with the UBR

I thought power levels could only affect weather you were actually connected to the network and stability, not actual download/upload speeds?

[Sirius]

I thought power levels could only affect weather you were actually connected to the network and stability, not actual download/upload speeds?

If your upstream is high then you will need to resend data constantly. That means that your download will suffer dramatically.

Imagine having to shout at a person a far distance off and he keeps saying SAY AGAIN.

[renty]

my area has 50 mb now, but im on 20mb and still docsis 1.0 with crap connection i was at 512 last night and max during day of 10-12mb at best.... area rg22 ....this has all changed since the 50 mb came out , whos getting the bum deal now....thats why i complained and now got 3 months free bb and phone ...untill its fixed...

[Ignitionnet]

As part of the configuration for the new CMTS such as the one you are now connected to they made a couple of adjustments in lieu of properly cleaning up the network. One of these is to increase attenuation and/or target receive power at the CMTS / uBR you connect to. On the upside it increases upstream SNR, on the downside it can cause serious issues for customers whose transmit power was a bit high before the change.

[monkey2468]

As part of the configuration for the new CMTS such as the one you are now connected to they made a couple of adjustments in lieu of properly cleaning up the network. One of these is to increase attenuation and/or target receive power at the CMTS / uBR you connect to. On the upside it increases upstream SNR, on the downside it can cause serious issues for customers whose transmit power was a bit high before the change.

Some of the return amp modules in the midlands can't do 47.4Mhz and there is no way of knowing which ones untill rollout.

[Ignitionnet]

Some of the return amp modules in the midlands can't do 47.4Mhz and there is no way of knowing which ones untill rollout.

Some of them all over the place have 5-40MHz or a bit more subsplits, my own being one which is why the 25.2MHz upstream channel was borrowed from the legacy platform. You'll see this quite often, especially on ex-Telewest networks.

This is where they were built based on the standard US DOCSIS frequency plan as opposed to EuroDOCSIS or extended subsplit DOCSIS. Lower split to account for that the first NTSC channel living at 52MHz.

That said the engineers will be very aware of the subsplits on the local networks, a spectrum analyser will show the capabilities just fine, there will be a rapid drop off of noise floor when you reach the top of the subsplit so it's not a case of 'suck it and see'. If the network weren't capable of that frequency customers wouldn't sync. No degraded service just none at all.

The techs are also supposed to be sweeping the networks before rollout - this means basically putting a device which will send a signal at a set strength across the entire return path spectum on a node and monitoring it with a spectrum analyser back at the hubsite to get an idea of the slope, gain, etc, of the return path and where networks may need adjustment.

Either way there is nothing special about the DOCSIS 3 kit, it's using DOCSIS 1.0 / 1.1 upstream and as I mentioned in a number of areas VM are simply borrowing a return frequency from the legacy platform so no extra stress on the RP lasers, however for those who are marginal when the extra attenuation and/or higher target Rx power to try and get more SNR out of the network is applied they go from marginal to unacceptable.

Ideally VM needed to get people out both sweeping and lining up the nodes and noise busting pre-rollout as was done in a couple of the trial areas, however the powers that be demand that 50M is rolled out yesterday so no time.

[monkey2468]

None of that was done here.

[caph]

Hi Broken Hope. At least we're off the dreaded BASF3!!!

I just got back in to the country last night and I'm shooting off again today but I've had a quick chance to check things. I am now on BASF9 registering with a docsis 1.1 config file and unfortunately I can confirm that download speeds are ranging between 6 and 9 Mbit both last night and this morning on this UBR. On the plus side I'm getting the best pings I've ever seen at around the 15ms level.

I've posted on the newsgroup to see if everything is finished regarding the upgrade or if it is still happening. I wouldn't be surprised if this is our final new improved 20Mb speed though, since our last UBR was so oversubscribed it often ran at 1% of headline speed.

As I was posting I noticed your thread underneath mine, I had to chuckle when I read their response to your complaint about oversubscription dated November 2008 "We do not have a SLA at this time but assure you this issue will be resolved as quick as possible". They seem to operate on a completely different time scale to the rest of humanity.

My upstream also jumped up and has now hit 54.8dBmV. Good luck trying to get it lowered though. I've had 4 engineers out so far all with the single purpose of dropping my upstream power and none did apart from the last one who simply moved me to another tap.

[Broken Hope]

Hi Broken Hope. At least we're off the dreaded BASF3!!!

I just got back in to the country last night and I'm shooting off again today but I've had a quick chance to check things. I am now on BASF9 registering with a docsis 1.1 config file and unfortunately I can confirm that download speeds are ranging between 6 and 9 Mbit both last night and this morning on this UBR. On the plus side I'm getting the best pings I've ever seen at around the 15ms level.

I've posted on the newsgroup to see if everything is finished regarding the upgrade or if it is still happening. I wouldn't be surprised if this is our final new improved 20Mb speed though, since our last UBR was so oversubscribed it often ran at 1% of headline speed.

As I was posting I noticed your thread underneath mine, I had to chuckle when I read their response to your complaint about oversubscription dated November 2008 "We do not have a SLA at this time but assure you this issue will be resolved as quick as possible". They seem to operate on a completely different time scale to the rest of humanity.

My upstream also jumped up and has now hit 54.8dBmV. Good luck trying to get it lowered though. I've had 4 engineers out so far all with the single purpose of dropping my upstream power and none did apart from the last one who simply moved me to another tap.

I noticed they replied to you on the newsgroup saying there are no utilisation issues on the UBR, how they can say that when people are only getting 6-9Mb speeds on a 20Mb connection is beyond me.

I'm not putting much hope in them fixing my connection, the last few engineers I've had out regarding upstream power have said that it's fine and left. One changed my connection in the box, I think as you said to put it on another tap but that did nothing.

[caph]

Yes, I just saw that too so I went throught the usual round of resetting everything and much to my surprise it has all jumped up to max speed. I'm downloading at over 2MByte/s now!

Sorry I can't be of more help. I am on a different UBR to you now though so there may be an issue with yours. It's worth asking the question on the newsgroup.

I'd like to find it in my heart to say something positive about my speed increase but 9 months of frustration has left me a little bitter.

I am looking forward to online gaming again though. Although I fear I may be a little rusty after 3/4 of a year.

[Broken Hope]

I'm not sure weather to laugh or cry, engineer just left. At first he had no idea even how to change power levels, so had to ring 2 different people, he finally got told how to and fiddled around inside the box outside and also fitted an anttenuator to the modem, this had brought my power levels to the following


Downstream Lock : Locked
Downstream Channel Id : 5
Downstream Frequency : 402750000 Hz
Downstream Modulation : QAM256
Downstream Symbol Rate : 5360.537 Ksym/sec
Downstream Interleave Depth : taps32Increment4
Downstream Receive Power Level : 3.5 dBmV
Downstream SNR : 39.9 dB

Upstream Lock : Locked
Upstream Channel ID : 4
Upstream Frequency : 37500000 Hz
Upstream Modulation : QPSK
Upstream Symbol Rate : 2560 Ksym/sec
Upstream transmit Power Level : 50.0 dBmV
Upstream Mini-Slot Size : 2

Which are all in spec right? Has made no difference at all to my download/upload speed in fact I think it's now worse.

The engineer then switched the modem out, this had already been done recently but oh well.

This new modem oddly connects to the old UBR's not the new upgraded ones, which doesn't make me a happy bunny to be back on the old Docsis 1.0 network, I hope this doesn't remain like this.

My host name is now cpc1-basf1-0-0-custXXX.nott.cable.ntl.com so I know for a fact I'm back on the old system.

The engineer then phoned up someone else whilst I was downloading 6 files, he was then told there's no issues on the network and basically said the fault is with my PC which is a load of crap, I know for a fact it isn't considering we have a laptop in the same house with the same issues, I've connected with and without the router so have ruled that out.

Getting to the end of my tether to be honest.

[Welshchris]

one thing i have noticed since the switchover here in swansea my upstream power level is higher than it used to be.

Where it used to be around 45 - 48dmbv now its 51 - 55dmbv

[caph]

Broken Hope, I spoke too soon. My lightning fast 20Mb broadband speed on the new 50Mb network is now 700K up and down, and that's still on the new BASF9.

I also now don't know whether to laugh or cry.

[Broken Hope]

Since they fitted me a new modem which I didn't actually need It's put me back on BASF1 instead of the new network, getting 2.3Mb which whilst slow seems faster than what you're getting at least..

Pretty much exhausted support it seems too since they claim over and over that the network is fine, no utilisation issues etc, so honestly not sure what I'm supposed to do now other than put up with crap service or change ISP which is not something I want to do at all since I'm on the VIP pack and would require me switching everything.

Though I honestly don't know how it can't be a network issue since at some times of the day I do get the full 20Mb, not times of the day when I could actually use the speed however.

[caph]

BASF9 is back up to 20Mb again. I think it was a regional issue but of course you can never tell with their useless service status page. I know that Virgin's internal systems went down yesterday which could be related. I lost my internet and TV for 24 hours prior to the slowdown so they must have been having some sort of network problem in my area.

In any case, when it is actually working, it looks like there is no oversubscription on BASF9 at any time of the day. I'm sure it's not right that you've been put back on the old network. I'd push them to get you switched back over so that they can fix whatever the problem is on BASF8.

One thing I don't understand is how you can connect to two different UBRs simply by switching modems. I always thought the cabinet to UBR connection was hard wired. Obviously not though.

[Zhadnost]

Nah, as I understand it, the 2 DS channels that are here (if they are both still here) on the old platform represent a different UBR each, and the 4 DS channels that have been added represent a different UBR.

Although that may be dependant on region, I have certainly (only once) been pushed from one to the other when I was on 20Mbit (although that was during maintenence, so that may have been an accident).

[Ignitionnet]

Nah, as I understand it, the 2 DS channels that are here (if they are both still here) on the old platform represent a different UBR each

Not quite, VM use MC28U line cards (http://www.cisco.com/en/US/products/hw/modules/ps4969/ps5219/index.html), where there are 2 downstreams they are the 2 downstream ports on the line card. Can't run the two across multiple CMTS as they are part of the same MAC domain and share the same upstreams.

---------- Post added at 15:56 ---------- Previous post was at 15:54 ----------

One thing I don't understand is how you can connect to two different UBRs simply by switching modems. I always thought the cabinet to UBR connection was hard wired. Obviously not though.

Nah not at all, it's like a radio, you can tune to many stations in the spectrum and aren't hard wired to any of them. On the VM network you are hard wired to a hubsite, and where you go from there depends on the downstream to upstream mappings on the network, and where your particular node, your group of a hundred homes, is wired to. You could be wired to 4 different CMTS so long as there are upstreams for each CMTS, that would be hugely inefficient though :)

[digitalspace]

Sorry to thread-hijack, but if my UBR has the "ntl" part in the string, I assume I'm on an old UBR and therefore unable to get 50mb?

Southampton BTW.

[BenMcr]

Southampton is 50Mbit enabled

[digitalspace]

I only ask, because an engineer was doing an install in a neighbours house last week and when I asked about 50mbit he said we couldn't get it yet.

I'll probably be better off calling them up. Will I notice any difference when my UBR changes to virginmedia.com , and is there any date for this changeover?

[Ben B]

I only ask, because an engineer was doing an install in a neighbours house last week and when I asked about 50mbit he said we couldn't get it yet.

I'll probably be better off calling them up. Will I notice any difference when my UBR changes to virginmedia.com , and is there any date for this changeover?

Your UBR will only change to virginmedia.net when you have 50mb, on all other tiers it will be NTL or Blueyonder AFAIK

[digitalspace]

Oh right, thanks for clearing that up :)

[Ignitionnet]

Your UBR will only change to virginmedia.net when you have 50mb, on all other tiers it will be NTL or Blueyonder AFAIK

Nah, on ex-ntl when you are on the new equipment which can be on either 20 or 50Mbit you will be virginmedia.net. On ex-BY this change doesn't happen.

Tracing route to www.virginmedia.com [212.250.162.12]
over a maximum of 30 hops:

1 2 ms <1 ms <1 ms 192.168.1.1
2 7 ms 7 ms 7 ms 94-172-192-1.cable.ubr06.mort.blueyonder.co.uk [94.172.192.1]

Name: 94-172-192-15.cable.ubr06.mort.blueyonder.co.uk
Address: 94.172.192.15

[Welshchris]

I only ask, because an engineer was doing an install in a neighbours house last week and when I asked about 50mbit he said we couldn't get it yet.

I'll probably be better off calling them up. Will I notice any difference when my UBR changes to virginmedia.com , and is there any date for this changeover?

according to thinkbroadband they have reported Virginmedia have completed the 50mb and docsis 3.0 rollout.

[BenMcr]

Er even the first line of the thinkbroadband article says 'Virgin Media is about to complete ' - from what I understand it means it should be 100% complete by the end of the month

[Ignitionnet]

according to thinkbroadband they have reported Virginmedia have completed the 50mb and docsis 3.0 rollout.

The press release claimed it at the start in the bullet points then corrected itself in the body, sloppy press release from overexcited marketing people I guess.