Is the web-socket on JVB only used to transfer SDP (or similar data) not video/audio stream?

I am reading this doc:

my first thought is that the jvb can use web-socket to relay the video/audio stream.

but when I read the first line again:
WebSockets can be used instead of WebRTC Data Channels for transport of Colibri client-to-bridge messages. This needs support from the bridge as well as the client.

it seems that the jvb only use the web-socket to transfer data (like SDP, offer and answer) not video/audio stream.

am I correct ?

Correct, we don’t transmit any media over websocket, just other data.

thanks. if the UDP is banned is there any other way to transmit the media ?

Yeah you can fallback to tcp by using a TURN server.

I am testing this way.
due to some reason, we have to set the port below 1024. but it report pair failed. (port 1024 is OK but 1023 fail)
do you think is it a ICE4j limitation or OS limitation ( jvb was running as root) ?

What was the error?

@bbaldino
JVB 2019-11-04 06:36:45.472 INFO: [162] org.ice4j.ice.ConnectivityCheckClient.log() Pair failed: 10.244.0.18:1023/tcp/host -> 172.26.122.1:9/tcp/host (stream.RTP)
JVB 2019-11-04 06:36:45.493 INFO: [162] org.ice4j.ice.ConnectivityCheckClient.log() Pair failed: 10.244.0.18:1023/tcp/host -> 172.26.122.17:9/tcp/host (stream.RTP)
JVB 2019-11-04 06:36:45.514 INFO: [162] org.ice4j.ice.ConnectivityCheckClient.log() Pair failed: 10.244.0.18:1023/tcp/host -> 172.16.106.189:9/tcp/host (stream.RTP)

JVB 2019-11-04 06:38:44.846 INFO: [128] org.ice4j.ice.ConnectivityCheckClient.log() Pair succeeded: 10.244.0.19:1024/tcp/host -> 10.244.0.1:51686/tcp/prflx (stream.RTP). Local ufrag cca381doqeo8qb
JVB 2019-11-04 06:38:44.846 INFO: [128] org.ice4j.ice.ConnectivityCheckClient.log() Pair validated: 172.26.122.25:1024/tcp/srflx -> 10.244.0.1:51686/tcp/prflx (stream.RTP). Local ufrag cca381doqeo8qb
JVB 2019-11-04 06:38:44.867 INFO: [128] org.ice4j.ice.ConnectivityCheckClient.log() Pair succeeded: 172.26.122.25:1024/tcp/srflx -> 10.244.0.1:51686/tcp/prflx (stream.RTP). Local ufrag cca381doqeo8qb
JVB 2019-11-04 06:38:44.867 INFO: [128] org.ice4j.ice.ConnectivityCheckClient.log() Pair validated: 172.26.122.25:1024/tcp/srflx -> 10.244.0.1:51686/tcp/prflx (stream.RTP). Local ufrag cca381doqeo8qb

here you can, port 1024 is working but 1023 not

Hmm, it looks like the in the failure case jvb is also seeing the discard port (9) as the remote port, which isn’t right–you can see there’s a proper port there in the working case.

hmmm. right. I need to investigate. this is automatically generated by remote