QUIC Lagging & Configuration

Question

I am running DCV in a docker container on an EC2 instance. When connecting using TCP/Websockets, i can get a smooth and good quality stream. When switching to QUIC, however, the stream essentially breaks completely. It sometimes only updates after a few seconds, compression artifacts are everywhere and in general we can get no smooth interaction at all to work.

So a connection is possible but completely unusable. 
I use the same port (8443) for TCP as for UDP, could this be an issue? Although technically it shouldn't be. This is unfortunate, as the picture quality on QUIC looks superior to the one with TCP.

I am using the Nice DCV Client to connect.

Thanks, Julian

Answer

Hello,

I understand you are getting not so good streaming quality on QUIC run from container.

Can you try limiting the maximum used bandwidth with using the below methods and see if you are getting better quality:

On Windows:

- Go to registry key: HKEY_USERS/S-1-5-18/Software/GSettings/com/nicesoftware/dcv/connectivity/
- Create a new QWORD: max-target-bitrate
- Set it to 20000 if you need maximum 20 Mbps (set another value, if 20 Mbps doesn't apply to your needs)

On Linux / MacOS:

- Open /etc/dcv/dcv.conf with your preferred text editor
- In the [connectivity] section, do the following:
~~~
[connectivity]
max-target-bitrate=20000
~~~
The above sets the value to maximum 20 Mbps (set another value, if 20 Mbps doesn't apply to your needs).

On Windows:
~~~
> dcvviewer.exe [...] --enabled-quic-alpn-versions="Dcv20Basic"
~~~

On Linux / MacOS
~~~
$ ./dcvviewer [...] --dqt-alpn-versions="Dcv20Basic"
~~~

Answer

Hi Julian,

in case QUIC from inside the container is slow it seems the network stack of the container environment is causing this slowness. Can you try DCV outside of the container to verify it working faster?

Best regards,
Karsten

QUIC Lagging & Configuration

Relevant content