IPsec VPN的RFC文档集合:
RFC 2401 《Security Architecture for the Internet Protocol》
RFC 2402 《IP Authentication Header》
RFC 2406 《IP Encapsulating Security Payload (ESP)》
RFC 2407 《The Internet IP Security Domain of Interpretation for ISAKMP》
RFC 2408 《Internet Security Association and Key Management Protocol (ISAKMP)》
RFC 2409 《The Internet Key Exchange (IKE)》
RFC 3947 《Negotiation of NAT-Traversal in the IKE》
RFC 3948 《UDP Encapsulation of IPsec ESP Packets》