120M : Uddingston upstream 3 channels?

[qasdfdsaq]

http://volpefirm.com/docsis101_anatomy-of-a-burst/

It's clearly described in the first paragraph...

tl;dr:

A time slot.

[Kushan]

yeah but thicko here is none the wiser as to what that means

[qasdfdsaq]

Cable uses TDMA for upstream:

https://en.wikipedia.org/wiki/Time_d...ultiple_access

tl;dr:

Upstream channels are shared using TDMA. In TDMA, multiple modems cannot transmit at the same time. Each second is divided into thousands of slots, and these slots are dynamically divided between modems. Each modem then transmits in it's assigned time slot(s) so they don't interfere with each other.

And quoted from BV:

Speaking of time slots, in DOCSIS lingo, a time slot is actually referred to as a "mini-slot". A mini-slot is made of an integer number of "ticks", depending upon the configuration of the CMTS. One tick is equal to 6.25 ?sec (micro seconds). So when speaking of burst times for cable modems, think of really short durations!

It's actually much the same as 2G (GSM) mobile phones.

[General Maximus]

so presumably the time slots of larger on the business server (meaning less of them) because there are far fewer users compared to the residential service and thus thousands of slots don't need to be available per second in order to ensure everyone can transmit

[Ignitionnet]

Originally Posted by General Maximus

so presumably the time slots of larger on the business server (meaning less of them) because there are far fewer users compared to the residential service and thus thousands of slots don't need to be available per second in order to ensure everyone can transmit

People on the business service connect to the exact same kit as people on the residential service and use the same upstream and downstream channels.

As I mentioned there is no difference between the mini-slot sizes, just how they are written - one in bytes the other in ticks.

[General Maximus]

my upstream is back to kick ass speed again. It is defo something to do with the addition of the latest upstream channel. I used to max out at 1.42MB/sec but since the addition of a 3rd upstream channel it has been averaging 1.6-1.7MB/sec and atm it is edging towards the 2MB/sec mark which isn't bad for a Sunday evening.




Interestingly though, every time it starts to push itself it locks up. I think I have mentioned this in two other threads over the last few days and it has only started happening since the last firmware release/last upstream channel addition. In the two mins it took me to take the screen dump and cut it up, I went to type this out and upload the pic only to find I had lost my connection. All the leds on the shub were solid blue and I had to reboot it to get everything back to normal again. Might be something you want to get them to look in to because it is happening every 2 days now. I have had this shub for over a year and not had to reboot it once up and till now.

Edit: rebooting the shub has caused me to lose my 3rd upstream channel again. Interestingly though a qam16 has gone and not the new qam64

[Martin_D]

Just lost 1 upstream & 1 downstream channel

down.PNG

up.PNG



Test done over a 1 Gigabit Ethernet card

[Martin_D]

Downstream channel is now back

Downstream DS-1 DS-2 DS-3 DS-4 DS-5 DS-6 DS-7 DS-8
Frequency (Hz) 299000000 267000000 275000000 283000000 291000000 307000000 315000000 323000000
Lock Status(QAM Lock/FEC Sync/MPEG Lock) Locked Locked Locked Locked Locked Locked Locked Locked
Channel ID 89 85 86 87 88 90 91 92
Modulation 256QAM 256QAM 256QAM 256QAM 256QAM 256QAM 256QAM 256QAM
Symbol Rate (Msym/sec) 6.952000 6.952000 6.952000 6.952000 6.952000 6.952000 6.952000 6.952000
Interleave Depth I=12
J=17 I=12
J=17 I=12
J=17 I=12
J=17 I=12
J=17 I=12
J=17 I=12
J=17 I=12
J=17
Power Level (dBmV) 4.31 3.98 3.77 3.85 4.09 4.67 4.66 4.90
RxMER (dB) 38.26 37.94 37.94 37.94 38.26 39.40 38.26 38.61
Pre RS Errors
284 300 290 980 965 295 317 311
Post RS Errors
284 298 290 980 965 295 315 311


Network Log First Time Last Time Priority Error Number Description
03/09/2015 20:26:27 GMT 03/09/2015 20:26:27 GMT Error (4) 68000407 TOD established
03/09/2015 20:26:12 GMT 03/09/2015 20:26:12 GMT Notice (6) 84000510 Downstream Locked Successfully
03/09/2015 20:26:07 GMT 03/09/2015 20:26:07 GMT Critical (3) 82000400 Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
03/09/2015 20:25:47 GMT 03/09/2015 20:25:47 GMT Critical (3) 82000400 Received Response to Broadcast Maintenance Request, But no Unicast Maintenance opportunities received - T4 time out
03/09/2015 20:25:28 GMT 03/09/2015 20:25:28 GMT Warning (5) 84020200 Lost MDD Timeout
03/09/2015 20:25:27 GMT 03/09/2015 20:25:27 GMT Warning (5) 84020200 Lost MDD Timeout
03/09/2015 20:25:27 GMT 03/09/2015 20:25:27 GMT Warning (5) 84020200 Lost MDD Timeout
03/09/2015 20:25:27 GMT 03/09/2015 20:25:27 GMT Warning (5) 84020200 Lost MDD Timeout
03/09/2015 20:25:27 GMT 03/09/2015 20:25:27 GMT Warning (5) 84020200 Lost MDD Timeout