[Elecraft] Minimum bandwidth?

[Poul Erik Karlshøj (PKA)]

The key question is always latency.

Maybe the problems Lynn refers to is more due to very high jitter.

In my experience fairly high latency *can* be used - if the jitter is low. It will not make you feel like being directly on the rig and you may have to adapt your operating style.
But high jitter is hard to cope with mainly because the programs may stop and you need to re-start. It will drive you mad.

My non-scientific experience is: Programs like IP-Sound, HRD, TeamViewer, KPA500 and KAT500 remote software will suffer first. Other programs like WKRemote and K3iNetwork annd Skype are more robust (dont recall ever having had to restart WKRemote due to jitter).

I wonder what makes the difference. Maybe related to buffer control or some programs using TCP/IP and others UDP?

73/OZ4UN
Poul-Erik
Sent from my iPad

On 10 Apr 2016, at 18:52, Lynn W. Taylor, WB6UUT <KX3 at ColdRocksHotBrooms.com<mailto:KX3 at ColdRocksHotBrooms.com>> wrote:

Ignore the faster speed, it's the slower speed on non-symmetric service.

The key question is always latency.

You can check out a VoIP calculator if you want to play the numbers, but most VoIP (and most cellular service) run around 8 kilobits/second.  No one offers IDSL service anymore, but it'd work beautifully at 128k (symmetric) with bandwidth to spare.

Where the problem lies is in the way the line is provisioned.

Where I live, there is only one provider that's worthwhile, the local telco.simply doesn't have enough bandwidth from the local central office to their first router.  The cable company doesn't admit they have service, even though there is a drop to the house.

That doesn't stop the Telco from selling 7 megabit service -- over and over and over.

So, sometimes I get 7 millisecond pings.  A lot of the time it's single digits, but every minute it'll jump over 500 msec.  Right now it's averaging about 250 msec, and the maximum has been 998 msec.

I've seen more than 4000 msec. (4 seconds).

Imagine trying to snag some amazing DX, and having the audio just stop for four seconds.

I could buy a faster wire, but they won't add bandwidth from the C.O. to the rest of the internet, so the latency would be the same.  I'd buy slower if they offered it.

73 -- Lynn

On 4/10/2016 2:59 AM, John Langdon wrote:
At my remote transmitter site, I have 10 mbps 'down' and 1.2 mbps 'up' and
everything works fine.
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