Internal Servers Combined With Ipsec Vpn - 3Com 3C13636 Configuration Manual

3Com Router 3000 Ethernet Family
Configuration Guide
# Create a bidirectional NAT entry.
[3Com] nat overlapaddress 3 10.0.0.0 3.0.0.0 address-mask 24
# Configure an ACL.
[3Com] acl number 2000
[3Com-acl-basic-2000] rule 0 permit source 10.0.0.0 0.0.0.255
[3Com-acl-basic-2000] rule 1 permit source 10.1.1.0 0.0.0.255
[3Com-acl-basic-2000] quit
# On the WAN interface bind the address pool with the ACL.
[3Com] interface serial0/0/0
[3Com-Serial0/0/0] ip address 192.168.0.1 255.255.255.0
[3Com-Serial0/0/0] nat outbound 2000 address-group 1
# Assign IP addresses to LAN interfaces.
[3Com-Serial0/0/0] interface ethernet 1/0/0
[3Com-Ethernet1/0/0] ip address 10.0.0.3 255.255.255.0
[3Com-Ethernet1/0/0] interface ethernet 3/0/0
[3Com-Ethernet3/0/0] ip address 10.1.1.3 255.255.255.0
[3Com-Ethernet3/0/0] quit
# Configure static routing.
[3Com] ip route-static 3.0.0.0 255.255.255.0 serial0/0/0
[3Com] ip route-static 192.168.1.0 255.255.255.0 serial0/0/0
The IP address of the DNS server is 192.168.0.150/24.

11.5.5 Internal Servers Combined with IPSec VPN

I. Network requirements
The headquarters of a company is connected to the public network through Router 1
and to the branches through IPSec VPNs established over the public network.
All traffic between the headquarters and its branches is protected using IPSec, where
manually-established SAs, the security protocol of ESP, the encryption algorithm of
DES, and the authentication algorithm of SHA1-HMAC-96 are adopted.
At the headquarters, the WWW and FTP servers are located on the 10.110.10.0
segment. Router 1 provides access to these two internal servers, allowing the internal
users to access using private addresses and the external users to access using public
addresses.
The PCs of the headquarters and branches are located on 10.110.20.0/24 and
10.110.30.0/24 respectively. They use the address translation service provided by
Router 1, accessing the Internet with the public address of interface S1/0/0.
3Com Corporation
11-20
Chapter 11 NAT Configuration