Looking for some links to case studies or other documentation which
describe implementing VoIP between sites which do not have point to
point links. From what I understand, you can't enforce end-to-end QoS
on a public network, nor over tunnels. I'm wondering if my basic
understanding of this is flawed and in the case that it's not, how is
this dealt with if the ISPs of said sites don't have any QoS policies?