This can be used for example to route all users on continent A to proxies
on continent B. Useful if no proxy exists on continent A and the global
selection chooses a non-ideal proxy.
- Individually for each backend.
- For the proxy client (i.e. signaling server using cluster of proxies).
- For the proxy server / MCU.
The smallest bandwidth configured will be used, e.g. if a backend has a
larger limit than the MCU assigned for the stream, the limit of the MCU
server will be used.
This will prevent the overall MCU timeout to expire on the first proxy
request if that takes too long. With the shorter proxy timeout, the other
proxy servers will be retried if the first request timed out.
