[FFmpeg-devel] [PATCH v2] avformat: enable UDP IPv6 multicast interface selection

[Ignjatović, Lazar (RS)]

This message has been marked as Public on 03/20/2024 11:45Z.
On Wednesday, March 20, 2024 12:30 PM Rémi Denis-Courmont wrote:

> You're not supposed to guess the link ID from the local address. This is counter-sensical. And it's entirely possible to have the same LL address assigned to two interfaces (e.g. using a software bridge) anyway.

You are right about the same LL on multiple interfaces, that’s why the `sin6_scope_id` is used. For specifying LL address, a scoped address format should be used to avoid ambiguity. In all other cases, determining the interface ID by address should be ok, while keeping the same functionality that `localaddr` param has with IPv6. Currently, I don't see any other way of specifying IPv6 multicast interface without the introduction of another query param like `iface` or something.

Let me know what you think.

Sincirely,
Lazar Ignjatović
Associate Software Engineer

Cubic Defense
cubic.com