[Bloat] [aqm] the side effects of 330ms lag in the real world

[Jan Ceuleers]

On 04/29/2014 07:01 PM, Toke Høiland-Jørgensen wrote:
> However, as that graph shows, it is quite possible to completely avoid
> bufferbloat by deploying the right shaping. And in that case fibre
> *does* have a significant latency advantage. The best latency I've seen
> to the upstream gateway on DSL has been ~12 ms.

I am not an expert, but I believe that this is due to the use of
interleaving. This is a method to improve the strength of forward error
correction by spreading out the effects of impulse noise on DSL lines
across multiple reed-solomon-protected codewords at the expense of latency.

The topic is briefly discussed on the ADSL Wikipedia page.