[strongSwan] Configuration Help needed on StrongSwan VPN server

[SaRaVanAn]

Hi Friends,

Topology
+++++++

Cisco VPN client --------- Router (StrongSwan)
------------Internet--------VPN_Server(StrongSwan).

10.1.1.1                           10.1.1.2
172.31.114.227                             172.31.114.239


I want to establish a remote access VPN between Cisco VPN client and
StrongSwan VPN server.

I also want to establish a site-site VPN tunnel between Router and
StrongSwan VPN server.

In both the cases, I dont know the source IP address(IP address of
cisco VPN client and

Router (which is dynamically changing)) .So I need a configuration on
Strongswan VPN server to form a tunnel with cisco VPN client without
mentioning its IP address and also to form a tunnel with Router, whose
IP is dynamically changing so I cant bind IP addresses in both the
cases.

It would be of great help, if someone shares the configuration file
for StrongSwan VPN server for the above scenario.

Regards,
Saravanan N