[Bloat] The bigger picture: whats components are used together to fight bloat

[Mikael Abrahamsson]

On Thu, 2 May 2013, Michael Richardson wrote:

> I anticipate similar problems trying to provide VoIP over (initially: 
> stationary) 3G.  Two providers have promised me that I'll be able to do 
> PPP directly to the devices, but when they show me a price list, it's 
> clearly for whole(re)sale.  I think the sales people don't understand 
> that they are lying, so I have less details on this.

Even if you do ppp to the device, you're still not the bottleneck. Every 
3G pluggable device I'm aware of does its own scheduling and just 
emulates/spoofs the ethernet/ppp layer so it's easier to integrate into 
the operating system. I wouldn't be surprised if most phones were done the 
same way, the OS of the system talks to the baseband part, but the 
baseband part does its own queueing.

> So the problem is that we can't always know what amount to shape things
> with.   As I am working with a vendor of CPE and access devices which
> says that they have an SDK, I attempting to put together a project to do
> measurements.  I will control the layer-3 devices at each end of the PPP(oE)
> link...

If you want to be able to do sane scheduling on 3GPP devices then you need 
to interact with the APIs provided to do traffic prioritization the 3GPP 
way. These are called "Traffic Flow Templates", but they basically just 
sorts packets according to criteria into different parallell queues 
(bearers) with different priority in the radio network. So you get a few 
FIFOs instead of just one.

-- 
Mikael Abrahamsson    email: swmike at swm.pp.se