Cable Forum - 50M Speed Doubling == More Upstream Capacity?

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Speed Doubling == More Upstream Capacity?

We have been waiting since July to get a fix for an upstream utilisation fault associated with our cable into sotn8 CMTS. Now and again, they change things and some of us get better graphs for a while although possbily at each others expense. There was a change last night (modem T4 event) and we saw these graphs:

mine (50M/docsis3):

http://www.thinkbroadband.com/ping/s...05-12-2012.png

neighbour1 (10M/docsis2):

http://www.thinkbroadband.com/ping/s...05-12-2012.png

neighbour2 (10M/docsis3):

http://www.thinkbroadband.com/ping/s...05-12-2012.png

The question is will the Speed Doubling work due to complete by the end of this month for our area bring the necessary upstream capacity to fix these current problems or is this wishful thinking?

Many thanks!

Re: Speed Doubling == More Upstream Capacity?

The TBB graphs don't support your question. But I can comment on the TBB graphs.

They show different characteristics, particularly neighbour 2. I wouldn't mind seeing their upstream and downstream stats to see what channels/frequencies are being used.

It strikes me that the three users are doing different things on their connection. However, neighbour 2's packet loss is worth a look. It could be due to upstrea noise (but why woult it suddenly happen?); or upstream contention (but then average ping would rise significantly). Maybe modem stats will tell us more.

BTW, whenn posting TBB graphs, post the smaller images so we can see them all on one screen!

Cheers

Re: Speed Doubling == More Upstream Capacity?

it is going to get fixed soon dude because they are in the process of bonding upstream channels (relieves congestion) in preparation for the speed increases

Re: Speed Doubling == More Upstream Capacity?

Quote:

Originally Posted by General Maximus (Post 35507327)

it is going to get fixed soon dude because they are in the process of bonding upstream channels (relieves congestion) in preparation for the speed increases

Sounds encouraging! Does this mean I have to switch to a SuperHub (modem mode) to benefit from this or can I stay with my VMNG300?

---------- Post added at 19:16 ---------- Previous post was at 18:53 ----------

Quote:

Originally Posted by Sephiroth (Post 35507321)

BTW, whenn posting TBB graphs, post the smaller images so we can see them all on one screen!

Reduced the graph sizes, sorry about that .. but they are there to show the current problem that I am hoping the speed doubling will solve.

The stats for my (50M/docsis3) service are:

Quote:

Cable Modem Upstream
US-1 US-2 US-3 US-4
Channel Type 2.0 N/A N/A N/A
Channel ID 1 N/A N/A N/A
Frequency
(Hz) 45800000 N/A N/A N/A
Ranging Status Success N/A N/A N/A
Modulation 16QAM N/A N/A N/A
Symbol Rate
(KSym/sec) 5120 N/A N/A N/A
Mini-Slot Size 4 N/A N/A N/A
Power Level
(dBmV) 36.75 N/A N/A N/A
T1 Timeouts 0 0 0 0
T2 Timeouts 0 0 0 0
T3 Timeouts 121 0 0 0
T4 Timeouts 1 0 0 0

Cable Modem Downstream
DS-1 DS-2 DS-3 DS-4
Frequency 298750000 282750000 290750000 306750000
Lock Status
(QAM Lock/FEC Sync/MPEG Lock) Y/Y/Y Y/Y/Y Y/Y/Y Y/Y/Y
Channel Id 169 167 168 170
Modulation 256QAM 256QAM 256QAM 256QAM
Symbol Rate
(Msym/sec) 6.952 6.952 6.952 6.952
Interleave Depth I=12
J=17 I=12
J=17 I=12
J=17 I=12
J=17
Power Level
(dBmV) 4.45 4.36 4.47 4.55
RxMER
(dB) 37.09 36.61 36.84 37.36
Correctable
Codewords 3262 3939 3512 3687
Uncorrectable
Codewords 288 294 296 303

The neighbour #1 has these (10M/docsis2) stats:

Quote:

Downstream Channel
Lock Status Locked Modulation QAM256
Channel ID 170 Symbol Rate 6952000
Downstream Frequency 306750000 Hz Downstream Power 6.6 dBmV
SNR 41.5 dBmV
Upstream Channel
Lock Status Locked Modulation QAM16
Channel ID 1 Symbol Rate 5120 Ksym/sec
Upstream Frequency 45800000 Hz Upstream Power 33.2 dBmV

am unable to get the third modem stats at the moment although I do know it is a Superhub in modem mode ...

however what is interesting is that another VM customer waiting on this fix posted their graph on the VM forum and his graph looks very similar as the 10M/docsis3 one:

http://www.thinkbroadband.com/ping/s...98104c3a4.html

Thanks for the help!

Re: Speed Doubling == More Upstream Capacity?

bonding channels helps balancing but doesnt add extra capacity (unless new channels are also added to facilitate the bonding).

What I will say is a good sign is the fact there is a long delay for your speed doubling rather than it been done right away, this does suggest some sort of work is been done, but no idea what it might be.

Interesting one docsis10mbit graph improves whilst the other gets worse but its only one day of data and due to the narrow pipe nature of VM shared pipes its quite easy for performance to vary from one day to the next since a single user alone can have a singificant affect on utilisation.

Re: Speed Doubling == More Upstream Capacity?

you can stay with your vmng300. I am already on 2 upstream channels (not that i had a problem with speed before) and am looking forward to the 120/12 increase

Re: Speed Doubling == More Upstream Capacity?

Thanks for the stats. It confirms that neighbour #1 shares one of your downstream channel as well as your upstream channel.

So, in addition to whatever anybody else who shares your channels was doing in your segment, whatever your neighbour was doing at the time affects what yo were doing & vice versa. So quite a few variables there - butu I've no doubt the network capacity is the problem.