Higher Latencies being reported on Smartlink

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Smartlink has much higher Latency reported by the Flex Network monitor than before with softether VPN/.  (much higher meaning in the high 200 range compared to double digit Latency reports via the VPN connection)  Anyone else see this change ?  BTW the problem could easily be something I did during the Ver 2.0 changeover.
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K1UO - Larry

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Posted 1 year ago

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KC9NRN

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I am seeing higher latency and much better connection strength via OpenVPN from work where I have a fiber 50/50 connection. Latency via the OpenVPN is around 13ms, seeing average around 190ms via SmartLink.

I am enjoying the benefit of using SmartLink however, listening to QSO's while driving to work I had the iPad sitting on the seat next to me so I could hear things going on, had a few drop outs which is to be expected.


Best connection snapshot of running SmartSDR 2 for an hour.


Average connection via OpenVPN for an hour.

(Edited)
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K1UO - Larry

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exactly the same as I see.  Thanks
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KC9NRN

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At lunch time today I ran both equally 30 minutes each, it stayed the same, VPN was definitely better. Not knocking SmartLink but for less overhead it sure doesn't seem as efficient as OpenVPN. In my car on the iPad I LOVE the ease of just opening SmartSDR and it just works, no turning on the VPN, just tap and go, love it.
(Edited)
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Tim - W4TME, Customer Experience Manager

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We believe this is a false negative reading.  The SmartLink connection has much less overhead than a VPN and will provide better performance.
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KC9NRN

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Tim,

More drop outs occur for me using SmartLink than VPN so I'll keep an eye out and report back.

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Tim - W4TME, Customer Experience Manager

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SmartLink is not compatible nor was it designed to work with a VPN.  It was designed not to need or use a VPN
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KC9NRN

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Deleted, Tim was responding to Larry...

(Edited)
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EA4GLI - 8P9EH - Salvador

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"We believe this is a false negative reading. The SmartLink connection has much less overhead than a VPN and will provide better performance."

Had this been tested? Is there any supporting evidence to that statement? I think it is a very important issue if it is not just an odd occurrence and it is in fact an issue in 2.0

A lot of testing had to go into Smartlink... It's there any metered comparison between Smartlink and OpenVPN?

Thanks.
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Tim - W4TME, Customer Experience Manager

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Had this been tested?
Yes.

In a VPN, all traffic is encrypted, broadcast, unicasts and multicast packets in a bridge configuration.  SmartLink only encrypts the command and control channel which constitutes a small percentage of the server to client network traffic.  The vast majority is of the traffic is display data, audio data, and metering data which is not encrypted.  Less encrypted traffic, less overhead.

Furthermore, the Internet router (in most cases) is not doing the datagram encryption, it is the radio performing that function so the router is just processing packet flows (states). 
(Edited)
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Varistor

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Of course there is more latency. The Opus codec alone adds a minimum of 25 ms, more if higher levels of compression are being used. Add to that time for TLS/SSL encryption and the latency numbers go up.
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KC9NRN

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Good to know, thanks! 180ms is still nuts.
(Edited)
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Eric - KE5DTO, Official Rep

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I don't think the Opus is relevant as we use that for the Remote LAN audio transmissions as well (so it is present in both situations).
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John - K3MA

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I can confirm that I am also seeing about double the Latency on SmartLink then I have been seeing on my VPN connection for the last year or so.  VPN is typically around 70 ms and SmartLink is around 160 ms on the Network Diagnostics screen.

I have not tested if this Latency ms value is correct or not but either it has more latency or the Network Diagnostics tool needs to be fixed.
(Edited)
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Eric - KE5DTO, Official Rep

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Right.  So the question is whether the reported numbers are accurate.  It is our impression that the reported numbers for SmartLink are inflated, but we don't have a handle on why this would be at this point.  The bigger question is: What is the actual latency experienced?