NAT and IPSEC work together solution

Publication Date:  2012-07-27 Views:  113 Downloads:  3
Issue Description
When NAT work with IPSEC together,the two private lans will can't ping though to each other because of NAT.So the traffic can't go though IPSEC tunnel.
Handling Process
Set up a GRE tunnel,and apply IPSEC on the tunnel interface,so the two private lan can visit each other via IPSEC tunnel over GRE tunnel.
Root Cause
Because of NAT,although the IPSEC tunnel can establish,but the tow private lans can't visit each other.
Provide a solution to use NAT and IPSEC work together.