References

For more information about the protocols for securing L2TP and IP tunnels with IPSec, consult the following resources:

• RFC 2401—Security Architecture for the Internet Protocol (November 1998)
• RFC 2661—Layer Two Tunneling Protocol “ L2TP” (August 1999)
• RFC 3193—Securing L2TP using IPSec (November 2001)
• RFC 3715—IPsec-Network Address Transation (NAT) Compatibility Requirements (March 2004)
• Negotiation of NAT-Traversal in the IKE—draft-ietf-ipsec-nat-t-ike-08.txt (July 2004 expiration)
• UDP Encapsulation of IPsec ESP Packets—draft-ietf-ipsec-udp-encaps-09.txt (November 2004 expiration)

  Note: IETF drafts are valid for only 6 months from the date of issuance. They must be considered as works in progress. Please refer to the IETF Web site at http://www.ietf.org for the latest drafts.

For additional configuration information, see:

•  Configuring IPSec
•  Configuring Digital Certificates
•  Configuring IP Tunnels
•  L2TP Overview