I work on the company helpdesk, and I was asked a question in passing that I would like an answer to.
I understand that L2TP uses GRE to tunnel. I would like to know how internal gateways on the internet and local LAN routers, and ABR's know how to route GRE to the Right proxy or proxy/firewall.
There must be a configuration setting.
Is there other tunneling protocols that can work with L2tp?