Experimental topology: 
! []
Purpose:
Wuhan, Harbin branch and headquarters to establish a connection via ipsec vpn, achieve network access each other within both sides.
The main record ipsec configuration.
Pre-configured simulation environment, Wuhan and Harbin normal pc can go to access the public network, which is the network of the region
Wuhan export routing configuration:
<wuhan-r>dis ip rout | in Sta
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Routing Tables: Public
Destinations : 12 Routes : 12
Destination/Mask Proto Pre Cost Flags NextHop Interface
0.0.0.0/0 Static 60 0 RD 222.73.1.1 GigabitEthernet0/0/0
192.168.0.0/16 Static 60 0 RD 1.1.1.2 GigabitEthernet0/0/1
<wuhan-r>Harbin export routing configuration:
<wuhan-r>dis ip rout | in Sta
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Routing Tables: Public
Destinations : 12 Routes : 12
Destination/Mask Proto Pre Cost Flags NextHop Interface
0.0.0.0/0 Static 60 0 RD 222.73.1.1 GigabitEthernet0/0/0
192.168.0.0/16 Static 60 0 RD 1.1.1.2 GigabitEthernet0/0/1
<wuhan-r>Wuhan nat configuration:
<wuhan-r>dis acl 2000
Basic ACL 2000, 1 rule
Acl's step is 5
rule 10 permit source 192.168.0.0 0.0.255.255
<wuhan-r>dis nat ou
<wuhan-r>dis nat outbound
NAT Outbound Information:
-------------------------------------------------------------------------
Interface Acl Address-group/IP/Interface Type
-------------------------------------------------------------------------
GigabitEthernet0/0/0 2000 222.73.1.2 easyip
-------------------------------------------------------------------------
Total : 1
<wuhan-r>Harbin nat configuration:
<haerb-r>dis acl 2000
Basic ACL 2000, 1 rule
Acl's step is 5
rule 10 permit source 172.16.0.0 0.0.255.255
<haerb-r>dis nat out
<haerb-r>dis nat outbound
NAT Outbound Information:
--------------------------------------------------------------------------
Interface Acl Address-group/IP/Interface Type
--------------------------------------------------------------------------
GigabitEthernet0/0/0 2000 180.73.2.2 easyip
--------------------------------------------------------------------------
Total : 1
<haerb-r>Two-story configuration will not be covered.
Now Wuhan and Harbin internal pc can normally access. But Wuhan and Harbin pc can not visit each other, this time to configure ipsec v pn Wuhan and Harbin can achieve within the network can access each other.