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DrStrangLov
join:2012-03-28

DrStrangLov

Member

IP-based voice: Skype

I noticed on Skype's FAQ How much bandwidth does Skype need?, they indicated for Voice that a range of 30kbps to 100kbps is OK.

They also explain how to evaluate your connection, "To find out if your internet connection is fast enough to make a Skype call (using Skype for Windows Desktop):"

Is Skype working OK on Exede-5 or Exede-12?
Liberty
Premium Member
join:2005-06-12
Arizona

Liberty

Premium Member

I have a customer who does support for an industrial strength data base company.
40 hrs a week she RDP into corporate networks at the same time she is talking via Skype - E12

I have others who video Skype on E5

Jitter has a great deal to do with QoS of VOIP

N4ST
Jim
Premium Member
join:2005-11-25
Jersey, VA

N4ST to DrStrangLov

Premium Member

to DrStrangLov
I measured Skype video usage a while back, but sadly I did not keep a record. I just remember that a half-hour call once a week was perfectly tolerable for my level of usage on Exede-12 15GB. I have only used it a half dozen times and audio/video quality varied considerably from one call to the next, I guess because the calls were in the evening and subject to congestion. I had the best luck with my Android phone and an Exede WiFI connection. I don't know if it was just a statistical quirk or whether the phone had a better implementation of Skype and also a smaller screen.
DrStrangLov
join:2012-03-28

DrStrangLov

Member

said by N4ST:

Skype video....audio/video quality varied considerably...subject to congestion

ViaSat's DAMA may be invoked during congested periods, for those not using their VOIP.

In Wildblue days, up North in Canada, I recall they used DAMA, but if using VOIP, they put those users on a separate channel or something.

In any event, those using VOIP up there had low latency, 600 ms or so, while the rest had much higher latency. In US, Wildblue never allowed VOIP "channels" when DAMA was activated in Nov. 2006.

Interesting to see if Exede is giving priority preference to their pay VOIP, while not giving same treatment to other VOIP services, especially with FCC's Net Neutrality.
wh7qq
join:2012-06-12

wh7qq

Member

Pardon, but what is a DAMA?
DrStrangLov
join:2012-03-28

DrStrangLov

Member

DAMA SATCOM Concepts, Modes, and Voice Services

ViaSat "designed, developed, built, certified, and fielded tested" for U.S. government a turnkey trainer/simulator.

When lots of users exist, DAMA format will be used. I have no idea where the idea started, but its been around since 1994.
viasatguy
Premium Member
join:2002-06-11
Carlsbad, CA

viasatguy

Premium Member

Demand Assigned Multiple Access

The notion is simple. Rather than using a fixed allocation or assignment for each user that is nailed up all the time, resources are allocated on demand.

In this way, limited resources can be shared among many users.

The demand assigned asset can be for example, a frequency channel, a time slice, or a spreading code. These would apply as appropriate in the case of frequency division multiple access, time division multiple access, or code division multiple access.
DrStrangLov
join:2012-03-28

DrStrangLov to wh7qq

Member

to wh7qq
said by wh7qq:

DAMA?

It's embedded into their equipment, and as more active users come onboard, it takes longer to initially fetch requests; once your turn exists, then it is fetched and delivered on Exede-5/12.

As N4ST noted (2008-Dec-21 »[general] Latency ? ) " By lengthening the DAMA time slots you can pass more data in a given time slot, waste less time with the overhead for time slot transitions, but you have to wait longer for your slot to "come around". This makes for greater latency and makes short stop/start transfers like browsing (especially https) seem extra slow."

In Wildblue days, they did not have AcceleNet servers, but fetching was done at Gateway itself. AcceleNet servers have a much larger pipe than what Gateways had, and in some (one) cases are located in same complex with other internet servers (Google, Game servers, etc). Hence, AcceleNet servers will reduce fetching time, when compared to Gateway fetching.

With VOIP, I would suspect a dedicated "time slice" is required to upload/receive packets. Waiting for "your turn" screws the VOIP pooch.

james1979
Premium Member
join:2012-10-09
Quinault, WA

james1979 to DrStrangLov

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to DrStrangLov
said by DrStrangLov:

Is Skype working OK on Exede-5 or Exede-12?

I have posted before about Skype voice on an Android phone and Exede-12, so my posts are searchable. Skype is not expensive, and as advertised, it is not intended to be a reliable phone service.

I cancelled Skype for two primary reasons:

I usually had a problem even making a call with Skype. I would call someone, there would be one or two "rings", and then Skype would disconnect. It sometimes took several calling attempts to establish a connection. This issue turned out to annoy others more than me.

And then of course their is the latency problem with Skype and satellite. I anticipated problems with elderly relatives, but there were universal complaints about Skype that were only managed by adopting the "over" and "over" and "over" and then eventually "out" protocol. This problem was of course exacerbated when communicating with a mobile phone (around 100 ms per one of your previous posts).

The voice quality was fine, and the SNR was so high as to be annoying. "Are you still there?" was asked frequently.

Now one variable to be considered was that I was using a very cheap junky phone with a CPU which was obviously recycled from a Commodore VIC-20. (It was Tracfone's first "smartphone" so I had no choice.) The dropped call problems occurred with terrestrial ISPs, so I have concluded that Exede was not causing that problem. That would narrow the problem down to either the deceased phone's hardware/software or else Skype's Android app.

A year later, I bought a Tracfone Android smartphone with a quadcore processor for less than I paid for this keyboard. The phone doesn't crash routinely, and my apps seem to function, well, more smoothly. (And I no longer need to use a stylus!) Given that the Skype phone number which I bought was not cancelled along with my service, I will likely give Skype another try as it is so inexpensive.

Oh, another topic has reminded me that it is quite possible and even legal to have Skype voice conversations on airline flights which offer Internet service. (But don't argue with the flight attendant when she is compelled to notify the captain.)
DrStrangLov
join:2012-03-28

DrStrangLov

Member

said by james1979:

Skype voice on an Android phone and Exede-12

When more active-users exist on a beam, the timing-response will be affected when an user is not allowed a dedicated "time slice."

On original US Wildblue, when DAMA was invoked, it appeared to be operating in a fixed mode. But, on Exede-12, I wonder if DAMA is dynamic, so that when only a few users exist, timing-response is lessened.

thx for tidbits...

legal to have Skype voice conversations on airline flights which offer Internet service.

Keep in mind, "Dec. 30, 2014 - The Transportation Department will decide in 2015 whether to keep a ban on voice communications on flights to, from and within the U.S. The rule, which was scheduled to be out this month, has been delayed and new rules are due in April."
Liberty
Premium Member
join:2005-06-12
Arizona

Liberty to james1979

Premium Member

to james1979
"Oh, another topic has reminded me that it is quite possible and even legal to have Skype voice conversations on airline flights which offer Internet service."

Just because one 'can' doesn't equal 'should'.
I just hope courtesy trumps whatever the courts decide...
ExedeDiana
join:2015-02-17
Englewood, CO

ExedeDiana to DrStrangLov

Member

to DrStrangLov
Hi DrStrangeLov, Skype does work with Exede Internet Service. I have worked with several customer who use. I would also like to thank the forum for your replies. Exede Diana

james1979
Premium Member
join:2012-10-09
Quinault, WA

james1979 to DrStrangLov

Premium Member

to DrStrangLov
said by DrStrangLov:

thx for tidbits...

Since I've already paid for my Skype number for couple of months, I went ahead and paid $3 for a month's worth of unlimited calling (to the USA and Canada). I made a few "Hi! How's the weather?" calls, and then I called my landline a boring number of times. My previous problem of "dropped rings" (two rings and then a disconnect) did not surface.

The voice quality was not as good as I remember it, while the latency was not as bad a I remember it. The SNR was still quite high. During one conversation where the callee was indoors, I could hear a train which was 1/2 mile away.

(Oh, I had to disable Adblock Plus and Ghostery to get Skype's website to work correctly with Firefox.)
said by DrStrangLov:

"Dec. 30, 2014 - The Transportation Department will decide in 2015 whether to keep a ban on voice communications on flights ...

That was an interesting article which I missed, but the article is only accessible by WSJ subscribers (which we both apparently are).
james1979

james1979 to Liberty

Premium Member

to Liberty
said by Liberty:

Just because one 'can' doesn't equal 'should'.
I just hope courtesy trumps whatever the courts decide...

Oh, I agree twice!

I was just experimenting to see if Skype voice would work on an airliner. Unrelated experiments of mine included seeing what would happen when I called my mobile Skype number from my mobile phone and also calling my mobile phone number from my Skype number. (My call was directed to someone else's Skype account, and then, as expected, that didn't work.)