Network system and communication apparatus for performing communication among networks having different VLAN settings

• US 9,923,733 B2
• Filed: 08/28/2012
• Issued: 03/20/2018
• Est. Priority Date: 08/28/2012
• Status: Active Grant

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: Shigeeda, Tetsuya, Honda, Shingo
• Primary Examiner(s): Huynh, Dung B
• Application Number:
  US14/423,738
• Publication Number:
  US 20150244543A1
• Time in Patent Office: 2,030 Days
• CPC Class Codes: H04L 12/18 for broadcast or conference , e.g. multicast
• CPC Class Codes: H04L 12/40 Bus networks
• CPC Class Codes: H04L 12/4641 Virtual LANs, VLANs, e.g. virtual private networks [VPN] LAN interconnection over a bridge based backbone H04L12/462; encapsulation techniques H04L12/4633; routing of packets H04L45/00; packet switches H04L49/00; virtual private networks for security H04L63/0272
• CPC Class Codes: H04L 2012/40293 the transportation system being a train
• CPC Class Codes: H04L 45/72 Routing based on the source address
• CPC Class Codes: H04L 47/10 Flow control; Congestion control

Abstract

A network system that comprises a plurality of communication apparatuses, each of the communication apparatuses being capable of performing a VLAN setting by using a VLAN number set for a connection port, that sets a VLAN number for each of the communication apparatuses, and that performs communication among cars of a train, wherein in a case where a specific type of packet that disables a VLAN setting is a packet of a multicast address, when a distribution target apparatus is connected to a communication apparatus that has received the specific type of packet, the communication apparatus transfers the specific type of packet to the distribution target apparatus and, irrespective of a VLAN number set for another communication apparatus, regards a VLAN different from a VLAN of the communication apparatus as a same network and transfers the specific type of packet to the another communication apparatus.

Claims

1. A network system comprising:

a plurality of communication apparatuses, each of the communication apparatuses being capable of performing a VLAN setting by using a VLAN number set for a connection port, that sets a VLAN number for each of the communication apparatuses, and that performs communication among cars of a train, wherein

the communication apparatus determines, on a basis of information that is given to a packet and identifies a type of communication, whether a received packet is a packet that is set to be permitted to pass and is a specific type of packet that disables a VLAN setting, and in a case where the communication apparatus receives a packet of a multicast address as the specific type of packet, when a distribution target apparatus is connected to the communication apparatus, the communication apparatus transfers the specific type of packet to the distribution target apparatus, disables setting of a VLAN number set for another communication apparatus, regards a VLAN different from a VLAN of the communication apparatus as a same network, and transfers the specific type of packet to the another communication apparatus.

2. The network system according to claim 1, wherein the specific type of packet is a packet having a specific MAC address.

3. A network system comprising:

a plurality of communication apparatuses, each of the communication apparatuses being capable of performing a VLAN setting by using a VLAN number set for a connection port, that sets a VLAN number for each of the communication apparatuses, and that performs communication among cars of a train, wherein

the communication apparatus determines, on a basis of information that is given to a packet and identifies a type of communication, whether a received packet is a packet that is set to be permitted to pass and is a specific type of packet that disables a VLAN setting, and in a case where the communication apparatus receives a packet of a unicast address as the specific type of packet, when a destination of the specific type of packet is an apparatus connected to the communication apparatus, the communication apparatus transfers the packet to the apparatus at a desired destination and, when a destination of the specific type of packet is an apparatus connected to another communication apparatus, the communication apparatus disables setting of a VLAN number set for the another communication apparatus, regards a VLAN different from a VLAN of the communication apparatus as a same network, and transfers the specific type of packet to the another communication apparatus.

4. The network system according to claim 3, wherein the specific type of packet is a packet having a specific MAC address.

5. A communication apparatus comprising:

at least one connection port, wherein the communication apparatus is in a network system that comprises a plurality of communication apparatuses, each of the communication apparatuses being capable of performing a VLAN setting by using a VLAN number set for a connection port, and wherein the communication apparatus sets a VLAN number for each of the communication apparatuses, and that performs communication among cars of a train, wherein the communication apparatus determines, on a basis of information that is given to a packet and identifies a type of communication, whether a received packet is a packet that is set to be permitted to pass and is a specific type of packet that disables a VLAN setting, and in a case where the communication apparatus receives a packet of a multicast address as the specific type of packet, when a distribution target apparatus is connected to the communication apparatus, the communication apparatus transfers the specific type of packet to the distribution target apparatus, disables setting of a VLAN number set for another communication apparatus, regards a VLAN different from a VLAN of the communication apparatus as a same network, and transfers the specific type of packet to the another communication apparatus.

6. The communication apparatus according to claim 5, wherein the specific type of packet is a packet having a specific MAC address.

7. A communication apparatus comprising:

at least one connection port, wherein the communication apparatus is in a network system that comprises a plurality of communication apparatuses, each of the communication apparatuses being capable of performing a VLAN setting by using a VLAN number set for a connection port, and wherein the communication apparatus sets a VLAN number for each of the communication apparatuses, and that performs communication among cars of a train, wherein the communication apparatus determines, on a basis of information that is given to a packet and identifies a type of communication, whether a received packet is a packet that is set to be permitted to pass and is a specific type of packet that disables a VLAN setting, and in a case where the communication apparatus receives a packet of a unicast address as the specific type of packet, when a destination of the specific type of packet is an apparatus connected to the communication apparatus, the communication apparatus transfers the packet to the apparatus at a desired destination and, when a destination of the specific type of packet is an apparatus connected to another communication apparatus, the communication apparatus disables setting of a VLAN number set for the another communication apparatus, regards a VLAN different from a VLAN of the communication apparatus as a same network, and transfers the specific type of packet to the another communication apparatus.

8. The communication apparatus according to claim 7, wherein the specific type of packet is a packet having a specific MAC address.