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Morac

macrumors 68020
Original poster
Dec 30, 2009
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I decided to run a speed test while on a VoLTE call with AT&T. I know it was VoLTE because the LTE symbol remained during the call.

Anyway, I used the Ookla Speedtest before, during and after the call to the same server. The results were as follows:

Before ping 43 ms, 60.30 Mbps down, 21.42 Mbps up.
During ping 59 ms, 36.66 Mbps down, 10.63 Mbps up.
After ping 38 ms, 60.32 Mbps down, 16.12 Mbps up.

As you can see during the call, the ping increased, download speeds dropped by about 40% and uploads drop by around half.

If the phone didn't say LTE and the Speedtest didn't report LTE, I would think it dropped to HSPDA+.

Is this normal?
 
That's too fast for HSPA these days. Idk why that happened but could be a requirement as the VoLTE call would need priority. I see nothing wrong here though.
 
I could be missing something, but VOLTE means you're using your data connection for a voice call, no? So your bandwidth is being used by the call, no? So it would be normal to see a drop in speeds, wouldn't it?

Yes, pretty much.
It's like doing a Speedtest while listening to pandora.
There's something in the back using data and that's the volte call.
 
I could be missing something, but VOLTE means you're using your data connection for a voice call, no? So your bandwidth is being used by the call, no? So it would be normal to see a drop in speeds, wouldn't it?

I would expect a minuscule drop in speed. There's no way a voice call uses 20 Mbps worth of data. It would use a few Kbps at most.

On a side note, I've seen HSPA+ speeds in at least the 20 Mbps range before. I'm not sure if I've ever seen over 30 Mbps though.
 
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I would expect a minuscule drop in speed. There's no way a voice call uses 20 Mbps worth of data. It would use a few Kbps at most.

Its throttled. AT&T has been throttling data while on a call now for years. It got to the point where when you were on 4G, you would get no more than 1Mbps while on a call.
 
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Its throttled. AT&T has been throttling data while on a call now for years. It got to the point where when you were on 4G, you would get no more than 1Mbps while on a call.

Yes, I remember that.
I don't see the reason behind it but when I did a Speedtest while on call the speed was around 1mbps.
Either way 36mbps is still great. I wouldn't worry about it if I was the op.
 
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