Plusnet VDSL config settings

Installing and Using OpenWrt Network and Wireless Configuration
1

Hi everyone,
Just starting with LEDE and got it installed on a HH5, I have a connection up and working but I don't get very stable graphs on DSLreports and I'm concerned there's optimisations I should have made.
I'm on a 79D/19U plusnet vdsl connection and my main focus is reducing latency for gaming!
Some queries
PPPoE ?
dsl encapsulation PTM ?
VCI 32 ?
VPI 1 ?
Do I apply sqm to ptm0.101 or wan?
I'm happy to try and figure it out if a confirmed source I can read up on but everything google brings up seems to conflict, particularly on the above .
Thanks in advance
Andrew

2

Yes, Plusnet uses PPPoE for VDSL connections. Yes, it is PTM. No, VCI and VPI are not relevant for VDSL. Yes, you can apply sqm to ptm0.101 or pppoe-wan and it does not seem to make much of a difference in my experience.

For more information consider Plusnet forum and Ebilan forum.

3

Erm, for pppoe links

Instantiate sqm on pppoe-wan, this makes sure PPPoE LCP packets are not dropped by the shaper...

1 Like
4

Yes, theoretically, this should be a reason to prefer pppoe-wan to ptm0.101. In my practical experience I used both and I don't see any difference.

5

Thank you for your help Savostyanov, I'll change to pppoe-wan and test that.
Reading more I now understand sqm is more about load fairness rather than prioritising a certain traffic(ie-gaming)but do you have any recommendations for settings to that may help me,i was wondering if layer cake maybe?
Thanks again

6

Well, there have been reports of people loosing their PPPoE link during heavy saturation, most likely due to sqm dropping the PPPoE LCP/keepalive packets... So I am happy that your experience is less troublesome, still, I would advise to instantiate on pppoe-wan....

7

Layer_cake will use the diffserv3 scheme with the following DSCP to priority tiers (or "tins" in cake-speak):
/* Simplified Diffserv structure with 3 tins.

  •          Low Priority            (CS1)

  •          Best Effort

  •          Latency Sensitive       (TOS4, VA, EF, CS6, CS7)

*/

cake will, requeue high priority packets into lower tins if the high priority bandwidth is used up, which mostly is nicer than strict dropping on over commit, but this also means that if you want high priority treatment to some flows you need to make sure to not over-commit....

And yes, sqm scripts goal is not to be a "meta" engine to conveniently allow all possible AQM and detailed QoS settings, but rather something that with very little configuration will mostly do the right thing. It turns out that the per-internal-IP-fairness that cake alllows, most users seem to be happy enough to not bther too much with detailed QoS magic (which, let's face it, is somewhat bothersome to initially set-up and will also need constant care to maintain).

8

hi moeller0, thanks for the info , would there be a noob friendly way of making sure my xbox traffic is considered latency sensitive, treated as highest priority?

9

The easiest, albeit not guaranteed way is to set up sqm/cake/layer_cake with per-internal-IP-fairness which should isolate the xbox traffic from all the rest by virtue of the xbox having its own unique internal IP address; combined with not using too many other computers at the same time ;). Anything else is somewhat hard as you will need to set the correct DSCP marking in packets from and to the xbox.

10

Thanks again for the help ,i'll give it a go and let you know the results.
Cheers andrew