Abstract: A domain gateway control system and a method are provided. The system includes a gateway device configured at an interface of a domain. The gateway device is further linked to more than one Ethernet. When the gateway device analyzes a data packet acquired from an Ethernet and detects that a destination MAC address data of the data packet points to a net device in the domain, the gateway device records a gateway MAC address data in a source MAC field of the data packet and records a domain type code data corresponding to the domain in an Ethernet-type field of the data packet to convert the data packet into a domain packet used in the domain. Any net device in the domain that acquires the domain packet learns the gateway MAC address data, and does not learn a device MAC address data of an external device of the Ethernet.

Abstract: A domain gateway control system and a method are provided. The system includes a gateway device configured at an interface of a domain. The gateway device is further linked to more than one Ethernet. When the gateway device analyzes a data packet acquired from an Ethernet and detects that a destination MAC address data of the data packet points to a net device in the domain, the gateway device records a gateway MAC address data in a source MAC field of the data packet and records a domain type code data corresponding to the domain in an Ethernet-type field of the data packet to convert the data packet into a domain packet used in the domain. Any net device in the domain that acquires the domain packet learns the gateway MAC address data, and does not learn a device MAC address data of an external device of the Ethernet.

Abstract: A multicast routing device, a network system applying the same, and a packet transmission method are provided. In the system, the multicast routing device is used to provide more than one multicast group point and is connected to a terminal device. When receiving a group switch command, the terminal device imports the address of a currently connected first multicast group point and the address of a second multicast group point to be switched to form a composite multicast packet including the addresses of the two multicast group points and then transmits the composite multicast packet onto a local area network on which the terminal device is located. When receiving the composite multicast packet, the multicast routing device interrupts connection of the terminal device and the first multicast group point and establishes a connection between the terminal device and the second multicast group point.

Abstract: The present invention relates to a network device and an authentication method thereof. When one network device is connected with another one, the two network devices may respectively receive and transfer an authentication reporting packet each other. Accordingly, the network devices may compare context of the received authentication reporting packet and a stored authentication type information, a digest information, and an authentication protocol information for determining whether process the following specific protocol packet according to the comparison result.