Can someone please share thoughts on the following topics for a CCNA guy.
1. What is GRE tunnel and why we really need that
2. What is the difference between point to point , point to multipoint GRE tunnel.
3. What is GRE keep alive and why we need it.
4. What is the fundamental/reason behind using GRE over IPSEC
5. Some sample configs of configuring point to point/point to multipoint GRE tunnels.
6.What IP addressing scheme and source/destination interfaces should be choosen while configuring GRE tunnels