bonding with rendez-vous mode

[walido2023]

Hi,
I am trying to implement the bonding feature for the possible SRT modes.
The documentation provided with the library has an introduction and some examples for the caller-listener couple, not for the rendez-vous mode.
I'm wondering if the bonding feature is already supported for rendez-vous mode?
If so, do you have an example to share with me?
Thank you

[maxsharabayko]

Hi @kawi2006
The rendezvous connection mode is not supported for SRT socket groups.

[walido2023]

Hi @maxsharabayko
Thank you for your quick feedback.
I have another question please:
For the caller-listener connection, in case when I have two SRT caller sockets which are sending the same payload to the server using bonding system.
Is it possible on the server side to create two sockets listener allowing to receive the same stream in bonding?
The idea is to make each SRT socket listen for a specific and independent network interface and manage received data in the bonding system.
Thank you.

[maxsharabayko]

For the caller-listener connection, in case when I have two SRT caller sockets which are sending the same payload to the server using bonding system.
Is it possible on the server-side to create two sockets listener allowing to receive the same stream in bonding?

Yes, it is possible. Just create several listeners, bind each to the required UDP port. And set SRT_GROUPCONNECT to 1.
One listener can also accept several connections of a single socket group.

[walido2023]

OK, but I got this message when two listener is used like a group to receive the same payload
"No room to store incoming packet: offset=51234 avail=0 ack.seq=734613160 pkt.seq=734664394 rcv-remain=8191 drift=0"
Do you have an idea please?

[walido2023]

This diagram may explain what I'm going to do.

[maxsharabayko]

Could you define which SRT version do you use? Seems like it is not v1.4.4, right?

Please also see these configuration guidelines.

[walido2023]

I'm using v1.4.3.
This feature is available from v1.4.4?

[maxsharabayko]

This feature is available from v1.4.4?

SRT v1.4.3 also supports this feature.
Just v1.4.4 has certain fixes for socket groups, and it makes sense to exclude them by using v1.4.4.
Also, the "no room to store..." log message has been improved (PR #1909).
It might be worth checking srt-xtransmit testing app, as it supports your use case.

[walido2023]

Thank you, the example helped me to find the root-cause.

Another question please: by migrating from SRT v1.3 to v1.4.3 the SRTO_MAXBW option no longer wants to be set.
flag = 0; //0=auto
if (srt_setsockopt(socket, 0, SRTO_MAXBW, &flag, sizeof(flag)) == -1) {
printf("srt_setsockopt(R) [SRTO_MAXBW] error ! [%s]\n", srt_getlasterror_str());
return -1;
}
it returns always -1
MESSAGE : srt_setsockopt(R) [SRTO_MAXBW] error ! [Operation not supported: Bad parameters]

Do you know what changes done between versions may impact this option?
Thank you

[maxsharabayko]

The flag variable must be of int64_t. Please ensure it is in your case. I don't see the type in your example.

[walido2023]

Yes it was the type :D
Thank you!

[ethouris]

Just to mention a general rule of bonding with using multiple listener sockets:

If you create a group (at the "caller side") and try to make multiple connections in the group, all of which will really be resolved into the same machine and application (if not, every next connection will fail), on the listener side the "accepted sockets" will also join the same mirror group upon reporting, no matter from which listener the sockets were extracted.