A method and system for using tunnel association information to allow network device to transfer and receive layer two packets through provide a layer two tunnel between different layer two networks through multiple network links. Layer 3 packets are used to encapsulate layer two packets. The tunnel association information includes a network link identification and a tunnel sequence number. The network link identification is used to identify the network link and virtual private tunnel said one or more layer three packets belonging to and the tunnel sequence number is used to identify the sequence of said one or mow layer three packets in a network link.