[CentOS-virt] xenbr0 vs. virtbr0

Just created the first completely new Xen VM with the Virtual Machine Manager after 5.0 became 5.1 and I notice these two differences:

- there's now virbr0 instead of xenbr0. Which means I have now xenbr0 and vitbr0 interfaces running. As virbr0 just the new name for xenbr0? If so, can I just change that name in the older configuration files, so that all use the same interface name?

- there is a (I think) new option for networking. There's virtual network and there's shared device. What's the latter? I don't remember this being available earlier. It doesn't list any devices for me. Does this refer to virtual devices of type eth0:5 etc. on the host?

help is no help for this, it's empty for this section.

Kai