
7-26
Cisco PIX Firewall and VPN Configuration Guide
78-15033-01
Chapter 7 Site-to-Site VPN Configuration Examples
Connecting to a Catalyst 6500 and Cisco 7600 Series IPSec VPN Services Module
Packets are processed by a pair of VLANs, one Layer 3 (L3) inside VLAN and one Layer 2 (L2) outside
VLAN. The packets are routed to the inside VLAN. After encrypting the packets the VPNSM uses the
corresponding outside VLAN. In the decryption process, the packets from the outside to the inside are
bridged to the VPNSM using the outside VLAN. After the VPNSM decrypts the packet and maps the
VLAN to the corresponding inside VLAN, EARL routes the packet to the appropriate LAN port. The L3
inside VLAN and the L2 VLANs are joined together by issuing the crypto connect vlan command.
There are three types of ports in the Catalyst 6500 series switches:
• Routed Ports—By default all Ethernet ports are routed ports. These ports have a hidden VLAN
associated with them.
• Access Ports—These ports have an external or VLAN Trunking Protocol (VTP) VLAN associated
with them. You can associate more than one port to a defined VLAN.
• Trunk Ports—These ports carry many external or VTP VLANs, on which all packets are
encapsulated with an 802.1q header.
Configuring IPSec Using a Trunk Port
Perform the following steps to configure an IPSec tunnel using the Catalyst 6500 trunk port
configuration:
Step 1 Add the inside VLANs to the inside port of the VPNSM. Assuming that the VPNSM is on slot 3, use
VLAN 100 as the inside VLAN and VLAN 200 as the outside, and configure the GE ports on the
VPNSM as follows.
interface GigabitEthernet3/1
no ip address
switchport
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 1,100,1002-1005
switchport mode trunk
interface GigabitEthernet3/2
no ip address
switchport
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 1,200,1002-1005
switchport mode trunk
Step 2 Add the VLAN 100 interface and the interface where the tunnel will be terminated (in this case,
FastEthernet2/2):
interface Vlan100
ip address 209.165.201.1 255.255.255.0
interface FastEthernet2/2
no ip address
switchport
switchport access vlan 200
switchport mode access
crypto connect vlan 100
Step 3 Create an ACL (in this case, ACL 100) defining the traffic from the inside network 10.10.10.0/24 to the
remote network 10.20.20.0/24:
access-list 100 permit ip 10.10.10.0 0.0.0.255 10.20.20.0 0.0.0.255
Commentaires sur ces manuels