Ike Aggressive Mode And Nat Traversal Configuration Example - 3Com 3C13636 Configuration Manual

3Com Router 3000 Ethernet Family
Configuration Guide
[3Com] ike proposal 10
# Set the authentication algorithm used by the IKE proposal to MD5.
[3Com-ike-proposal-10] authentication-algorithm md5
# Apply the pre-shared key authentication mode.
[3Com-ike-proposal-10] authentication-method pre-share
# Set the lifetime duration of ISAKMP SA to 5000 seconds.
[3Com-ike-proposal-10] sa duration 5000
2) Make the following configurations on the security GW B:
# Configure an IKE peer.
[3Com] ike peer peer
[3Com-ike-peer-peer] pre-shared-key abcde
[3Com-ike-peer-peer] remote-address 202.38.160.1
The configurations made above can ensure the proper IKE negotiation between GWs A
and B. As GW A is configured with proposal 10 and authentication-algorithm md5 but
GW B is configured with only a default IKE proposal and authentication-algorithm
sha, GW B will not have a proposal matching the IKE proposal 10 configured on GW A.
For this reason, the system will find only a match, that is, the default IKE proposal for
the both parties when it makes the match operation in proposals starting from the one
with the highest priority. In addition, no match operation will be done on duration in the
proposal matching process, as the lifetime is decided by the initiator of IKE negotiation.
For more information about the IPSec configurations, see "Section 7.4 Typical IPSec
Configuration Examples".

8.4.2 IKE Aggressive Mode and NAT Traversal Configuration Example

I. Network requirements
The LAN of a company branch is connected to the company intranet via a leased
line. The S0/0/0 interface of RouterA has a fixed IP address and Router B obtains
IP address from an ISP dynamically.
As the IP address obtained by the branch is a private one and the IP address of
the S0/0/0 interface on Router A is a public address, you must enable NAT
traversal on both Router A and Router B.
To ensure information security, IPSec/IKE is adopted to create a security tunnel.
3Com Corporation
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Chapter 8 IKE Configuration