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-   -   Superhub : Upstream channel bonding: Any plans to bond more than 2? (https://www.cableforum.uk/board/showthread.php?t=33704864)

Jon22 13-07-2017 18:23

Re: Upstream channel bonding: Any plans to bond more than 2?
 
Quote:

Originally Posted by Inactive Digital (Post 35907691)
I'm on Telf13 and still 2x16QAM.

Ah ok. My dad's is on Telf13 and that is on QAM64 now. Perhaps it's done node by node?

Travelstar 31-07-2017 07:23

Re: Upstream channel bonding: Any plans to bond more than 2?
 
Seems my 4th upstream channel vanished the other day, so now back at 3. Still only 8 downstream channels, but as during off-peak, this still delivers 200. Peak is another matter (approx 15-40), but that's a discussion for another thread.

Ignitionnet 13-08-2017 13:48

Re: Upstream channel bonding: Any plans to bond more than 2?
 
Quote:

Originally Posted by General Maximus (Post 35898351)
it is a shame Igni isn't around to provide more info, I haven't seen him in ages.

This had better be really good. What's up General?

---------- Post added at 13:42 ---------- Previous post was at 13:14 ----------

Quote:

Originally Posted by Sephiroth (Post 35898591)
Incidentally, if one channel is on 16QAM then that will drag the overall upstream capacity down. 16QAM has 4 bits per symbol & 64QAM has 6 bits per symbol. But because a data packet is split across all the upstream channels, it can only be reassembled at the bit density rate of the slowest channel.

A packet will almost always go on a single channel. Remember that the modem receives its grants in 2 or 4 ms increments, the CMTS scheduler tries to service each request on a single upstream, and what the minimum and maximum burst sizes are.

---------- Post added at 13:48 ---------- Previous post was at 13:42 ----------

So there is a programme to get all areas up to 4 upstreams, targeting 64QAM but obviously the modulations will respond to SNR drops on the channels.

Getting 4 upstreams at 64QAM requires either DFB lasers in the nodes or digitised return paths. In some areas nodes and amplifiers need replacing.

There are also issues in hubsites with regards to space and power. There are some areas where it took some quite extreme measures to get new CMTS in, or they haven't been installed yet and area awaiting those extreme measures. These will not have any space for new optics so will need some equipment and intelligence moved out into the field via Remote PHY and other options in the Distributed CCAP deployments.

It is possible to cram 4 upstreams into a 42MHz network but tricky, and areas that have this limitation have run out of downstream bandwidth anyway. There's also the problem of the legacy set top boxes and modems that need to be gotten rid of.

There are no plans to get all tiers onto 10:1 ratios, but some of them it's certainly doable.

Once areas are onto 24 downstream channels that's the end of the upgrades on that score. 4 upstream channels is not necessarily the end-game there.

DOCSIS 3.1 rollout will not be using 3.1 upstreams initially, it will use the same upstreams as the 3.0 network. This is not unusual, I'm not aware of any 3.1 deployments in the USA and Canada, where they are ahead of us, that are using 3.1 upstreams.

Business are likely to get higher speeds somewhat before residential.

General Maximus 13-08-2017 16:35

Re: Upstream channel bonding: Any plans to bond more than 2?
 
long time no see, welcome back

vm_tech 13-08-2017 16:53

Re: Upstream channel bonding: Any plans to bond more than 2?
 
[/QUOTE]
Getting 4 upstreams at 64QAM requires either DFB lasers in the nodes or digitised return paths. In some areas nodes and amplifiers need replacing.
[/QUOTE]

I've haven't worked on the network for a while, so could be wrong but I believe the digital returns for some reason can only go up to 65mhz, so VM are trying to move away from them. They are only used in segmentable nodes anyway. Although it's been a good 18 months so the situation may have changed!

Ignitionnet 13-08-2017 17:16

Re: Upstream channel bonding: Any plans to bond more than 2?
 
Quote:

Originally Posted by vm_tech (Post 35912274)
I've haven't worked on the network for a while, so could be wrong but I believe the digital returns for some reason can only go up to 65mhz, so VM are trying to move away from them. They are only used in segmentable nodes anyway. Although it's been a good 18 months so the situation may have changed!

Yeah indeed. Newer nodes have field replaceable diplexers that can switch from a 5-85MHz mid-split to a 5-200MHz high-split return path.

The plan going forward is to push towards Remote PHY, where there's a 10Gb Ethernet link to the node and the only RF segment is from node outwards, rather than sending an analogue carrier down the fibre. This will improve RF performance to the home and substantially reduces space requirements in the hub site.

Will require more power than existing nodes, though may be compensated for by improved power supplies and replacements of active amplifiers with nodes.

vm_tech 13-08-2017 18:42

Re: Upstream channel bonding: Any plans to bond more than 2?
 
I have heard about the 10gb Ethernet delivery to the cabinet. I also know the potential delivery method. Although I believe it is aimed at business customers rather than resi. But things change over time so who knows

Ignitionnet 13-08-2017 19:17

Re: Upstream channel bonding: Any plans to bond more than 2?
 
Quote:

Originally Posted by vm_tech (Post 35912306)
I have heard about the 10gb Ethernet delivery to the cabinet. I also know the potential delivery method. Although I believe it is aimed at business customers rather than resi. But things change over time so who knows

The 10G backhauls will be replacing the analogue laser run. The RF will be generated at the node, the node takes the place of the optical transmitter and receiver that are in the hubsite.

ileikcaek 13-08-2017 20:26

Re: Upstream channel bonding: Any plans to bond more than 2?
 
I'm just wondering when my area will actually see any upgrades after seemingly languishing for years. there's no 300Mb yet, upload is still on 2x QAM16, the CMTS is a RiverDelta hunk of junk with the current single thread download speed issues that I and other people in the area have had to deal with since last year. Tbb places this area as bottom of the chart for VM performance now, when it used to be one of the best.

vm_tech 13-08-2017 20:32

Re: Upstream channel bonding: Any plans to bond more than 2?
 
Quote:

Originally Posted by ileikcaek (Post 35912339)
I'm just wondering when my area will actually see any upgrades after seemingly languishing for years. there's no 300Mb yet, upload is still on 2x QAM16, the CMTS is a RiverDelta hunk of junk with the current single thread download speed issues that I and other people in the area have had to deal with since last year. Tbb places this area as bottom of the chart for VM performance now, when it used to be one of the best.

All CMTS's will be one of 2 different types eventually. Where are you?

ileikcaek 13-08-2017 20:34

Re: Upstream channel bonding: Any plans to bond more than 2?
 
Quote:

Originally Posted by vm_tech (Post 35912344)
All CMTS's will be one of 2 different types eventually. Where are you?

I'm in Dover, should have mentioned it. :)

Broken Hope 14-08-2017 13:43

Re: Upstream channel bonding: Any plans to bond more than 2?
 
Am I right in thinking that if I'm on 24 downstream channels then I'm on the newer, upgraded hardware?

Jon22 14-08-2017 13:51

Re: Upstream channel bonding: Any plans to bond more than 2?
 
Quote:

Originally Posted by Broken Hope (Post 35912418)
Am I right in thinking that if I'm on 24 downstream channels then I'm on the newer, upgraded hardware?

Yep, either a Arris E6000 or a Cisco cBR-8.

Mythica 14-08-2017 14:12

Re: Upstream channel bonding: Any plans to bond more than 2?
 
Quote:

Originally Posted by ileikcaek (Post 35912339)
I'm just wondering when my area will actually see any upgrades after seemingly languishing for years. there's no 300Mb yet, upload is still on 2x QAM16, the CMTS is a RiverDelta hunk of junk with the current single thread download speed issues that I and other people in the area have had to deal with since last year. Tbb places this area as bottom of the chart for VM performance now, when it used to be one of the best.

I'm in the same boat. 24 downstreams but only 2 x QAM16 upstreams. The other week the postcode checker said 300Mb was available but now that's disappeared and it now says 200Mb.

Ignitionnet 14-08-2017 14:49

Re: Upstream channel bonding: Any plans to bond more than 2?
 
I'll see what I can find out regarding Dover hub site.

With regards to bonding 4 upstreams not a clue what the hold up is. There are plenty of areas that are perfectly capable but just haven't had the configuration rolled out and it's holding things up.

---------- Post added at 14:49 ---------- Previous post was at 14:20 ----------

Dover is proving a real pain in the everything.

Should be upgraded within the next 2.5 months.


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