Re: [Bloat] Bufferbloat research: Help required

[Simon Barber <simon@superduper.net>]

Voice over data can actually work very well in 3G networks (better than 
dedicated voice even), but it requires prioritisation. There is a bunch 
of work going on to enable this in existing networks to support the new 
services that VoLTE will enable, over older networks (Joyn). This is a 
*huge* transition in carrier networks, and will take some time to 
arrive. Even today only 1 US carrier uses VoLTE, all the others switch 
to 3G to make or receive a phone call.

Simon

On Sat 01 Dec 2012 12:53:13 PM PST, Michael Richardson wrote:
>
>>>>>> "Mark" == Mark Watson <watsonm@netflix.com> writes:
>      Mark> It's also interesting to note that cellular wireless [DATA] systems
>      Mark> have been designed with a primary objective of reducing packet
>      Mark> loss, at the expense of delay and especially delay variability
>      Mark> introduced by link layer ARQ and other schemes. This approach
>      Mark> maximizes the throughput of a single long-lived TCP
>      Mark> connection, which is not an especially common traffic
>      Mark> pattern.
>
> A question, given that I inserted [DATA].
>
> I wonder to what extent the pre-LTE systems were designed this way in
> part to make sure that voice over data would always be crappy?
>
> The LTE roadmap says that voice is now over data, so it's now in the
> carrier's interest to do things differently.
>
>      Mark> Furthermore, the throughput of a cellular wireless radio
>      Mark> channel varies by orders of magnitude on fairly rapidly
>      Mark> (channel conditions are reassessed hundreds of times per
>      Mark> second): what was a reasonable sized buffer for the throughput
>      Mark> at one moment becomes a bloated one a fraction of a second
>      Mark> later.
>
> Does ECN help us here?
>