[MPlayer-users] udp sync over wifi

[Ron Johnson]

On 07/18/2012 02:19 PM, Richard Markiewicz wrote:
> I'm evaluating the UDP sync feature of mplayer (1.1 release) on Windows.
>
> It's working great so far. My machines are wired on a gig-E network and
> playback is perfectly in sync.
>
> I'd like to try it over WiFi. I tested with two machines:
> - My desktop (master), wired to the network over gig-E
> - My laptop (slave), connected wirelessly to the network over wireless G
>
> And performance is not good. In fact, it's nearly completely broken. The wifi
> slave skips and jumps throughout the whole file.
>
> (I'm testing this scenario with a very simple, standard definition video that
> the machines have no problem playing)
>
> Latency is very low on my wifi network. Ixia qcheck
> (http://reviews.cnet.com/4520-6603_7-5020854-1.html) tests show that UDP
> latency is around 1-3ms.
>
> So my question is - is wifi a supported/envisaged scenario? Is there an
> underlying technical reason why this would not work? Perhaps some
> configuration I can tweak that will help?
>

Bandwidth is the first presumption.  802.11g has a max theoretical 
throughput of only 6.75MBps, but can't actually reach that even at close 
range with 5 bars.  What with router placement, distance from laptop to 
router and what's in between the router and laptop, it gets worse very 
quickly.

That's why I recently added a dual-band 802.11n router in AP mode 
positioned more centrally in the building.  Note, though, that while 
5GHz N has much better bandwidth, it also has shorter range and is more 
easily blocked than 2.4GHz.

-- 
"There is usually only a limited amount of damage that can be
done by dull or stupid people. For creating a truly monumental
disaster, you need people with high IQs."
Thomas Sowell