Re: [Bloat] SQM Settings for Bonded DSL?

[Jonathan Foulkes <jf@jonathanfoulkes.com>]

Hi Rich, Sebastian,

Most bonded modems do a good job of making the line look just like a single, higher-capacity line. The only major issues I’ve observed is when the bonded lines have some asymmetry to them (e.g. one link has weaker SNR), then the bond drops, re-synchs and continues. But occasionally, it will run for extended periods at 50% capacity (i.e. on only one of the lines).
It uses PMT protocols, so not at all like mwan3, as any one connection can achieve full throughput of the bonded set.

I have data on hundreds of bonded lines, and other than the scenarios I mentioned above about bad bonds, as far as SQM goes, it behaves just like any other DSL line of equal capacity. So all the same guidelines would apply.

I hope that helps,

Jonathan Foulkes

> On Jun 21, 2018, at 7:14 AM, Sebastian Moeller <moeller0@gmx.de> wrote:
> 
> Hi Rich,
> 
> 
> 
>> On Jun 21, 2018, at 13:08, Rich Brown <richb.hanover@gmail.com> wrote:
>> 
>> Hi folks,
>> 
>> Our local DSL ISP (Consolidated Communications, Inc, formerly Fairpoint) recently installed a Smart/RG SR555ac (https://www.smartrg.com/sr555ac) bonded ADSL2 modem.
>> 
>> I seem to remember earlier messages stating that the dual queues in the DSL modem screwed up (or, de-optimized) the SQM in the router. 
> 
> 	As far as I can see this should not really cause an issue (besides that latency for single packets will be limited by the fact that you have two half-total-bandwidth links) except maybe that there might be additional overhead for the bonding on the link, but I have never looked at channel bonding so this is pure spekulation. I assume here that your Modem handles the bonding transparently. I could envision that running an non-transparent load-balancer (like with mwan3 under openwrt) might introduce issues for sqm, but if all you see is one ethernet link to the modem I do not expect any major quirks (except latency not being in line with the expectancy from total bandwidth).
> 
>> 
>> The web GUI does provide info on SNR, sync rates, etc. Any advice for SQM beyond the standard, "measure the no-SQM speed, then start at 5% below..."? Thanks.
> 
> 	I am curius myself and would like to ask you to keep me/the list posted on whatever you find out about the applicability of sqm to bonding.
> 
> Best Regards
> 	Sebastian
> 
> 
>> 
>> Rich
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