PACKET RELAY APPARATUS

• US 20080080533A1
• Filed: 02/15/2007
• Published: 04/03/2008
• Est. Priority Date: 09/29/2006
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Yamane, Shinji
• Granted Patent: US 8,085,795 B2
• Time in Patent Office: Days
• US Class Current: 370/401
• 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 45/04 Interdomain routing, e.g. hierarchical routing

Abstract

A unicast-use tunnel is added between the Note-C and GW-B (i.e., a unicast optimization). Then, the Note-C transmits, to a GW-C, a second IP packet encapsulating a first IP packet, to which an inter-GW header is added, by an IP header to which a multicast address is set. The multicast-use second IP packet is transferred to a CE by way of a tunnel. The CE copies the received second IP packet and transfers it to a GW-A and the GW-B by way of the tunnel (i.e., a multicast optimization).

Claims

1. A packet relay apparatus connecting a sub-network accommodated by the apparatus itself to a global network, grouping terminals within the sub-network virtually and building up a virtual private network by an inter-group member communication, comprising:

a storage unit which stores routing information, for use in an inter-group member communication, related to a main route, and a sub-route, of a first Internet protocol (IP) packet that is managed by an internal management transfer number for identifying a main route used for the inter-group communication, by a sub internal management transfer number for identifying a sub-route used for the inter-group communication, by a transfer number for identifying a transfer route of the first IP packet which is transferred to another packet relay apparatus and by a group number for identifying a group, and of a second IP packet for transmitting and receiving to and from a terminal under the control of the apparatus itself, and which stores route identification information that is information for identifying an event of being transferred by way of two routes, that is, the main route and sub-route;

an information management unit for setting, and updating, the management information and route identification information stored in the storage unit;

a first transmission/reception unit for transmitting and receiving the second IP packet between itself and the terminal under the control of the apparatus itself;

a first packet creation unit for creating the first IP packet by adding an inter-packet relay apparatus header including information for use between the group members, information related to the main route, the route identification information and a packet identification information for identifying a packet to the second IP packet received by the first transmission/reception unit by referring to the routing information and route identification information which are stored in the storage unit;

a second transmission/reception unit for transmitting the first IP packet created by the first packet creation unit to another packet relay apparatus by referring to the routing information and route identification information which are stored in the storage unit and also receiving the first IP packet addressed to a terminal under control of the apparatus itself from another packet relay apparatus; and

a second packet creation unit for creating the second IP packet by deleting the inter-packet relay apparatus header from the first IP packet received by the second transmission/reception unit and outputs the second IP packet to the first transmission/reception unit.

2. The packet relay apparatus according to claim 1, further comprising a transfer unit for transferring said first IP packet received by the apparatus itself to another packet relay apparatus by referring to said routing information and route identification information which are stored in said storage unit.

3. The packet relay apparatus according to claim 1, wherein

said second transmission/reception unit comprises an encryption unit for encrypting said first IP packet to be transmitted to another packet relay apparatus, and a decryption unit for decrypting said first IP packet received from another packet relay apparatus.

4. The packet relay apparatus according to claim 1, wherein

said management information is constituted by

a first table storing a sender identification number assigned to said first terminal and said group number of said group, to which the first terminal belongs, corresponding to a real IP address assigned to a first terminal under the control of the apparatus itself,

a second table storing an addressee identification information assigned to a second terminal which is a destination of said second IP packet transmitted by the first terminal, a group number for a group to which the first terminal belongs, said internal management transfer number and said sub-internal management transfer number,

a third table storing routing information of an IP packet corresponding to the internal management transfer number and storing routing information of the second IP packet corresponding to the sub-internal management transfer number, and

a fourth table managing routing information of the received second IP packet by the internal management transfer number, sub-internal management transfer number and group number.

5. The packet relay apparatus according to claim 1, further comprising

an update unit for updating said routing information and route identification information according to a condition of a route used by a terminal under the control of the apparatus itself for communicating said second IP packet.

6. The packet relay apparatus according to claim 1, further comprising

a storage unit for storing packet identification information for identifying said first IP packet if a terminal under the control of the apparatus itself receives the first IP packet addressed to the terminal from another packet relay apparatus in a duration of the terminal communicating the first IP packet by utilizing said main route and sub-route, and a delayed delivery discard process unit for discarding

a first IP packet belatedly received among two of the same first packet addressed to the terminal receiving from the main route and sub-route, based on the packet identification information stored in the storage unit.

7. The packet relay apparatus according to claim 1, further comprising

a communication route optimization unit for optimizing a communication route for said first IP packet by updating said routing information and route identification information.

8. The packet relay apparatus according to claim 7, wherein

said communication route optimization unit optimizes said communication route when a communication volume of said second IP packet exceeds a specified value at a terminal transmitting/receiving the second IP packet.

9. The packet relay apparatus according to claim 7, wherein

said communication route optimization unit optimizes said communication route when a transfer volume of said first IP packet exceeds a specified value at a packet relay apparatus placed at a relay spot of said communication route.

10. The packet relay apparatus according to claim 7, wherein

said communication route optimization unit optimizes said communication route stepwise.

11. The packet relay apparatus according to claim 10, wherein

said communication route optimization unit first adds a route for communicating said first IP packet so as to communicate said second IP packet in two routes as a first stage, followed by narrowing down to one route with a better transfer ratio of the second IP packet from the two routes communicating the first IP packet in a second stage.

12. The packet relay apparatus according to claim 11, wherein

a communication route optimized by said communication route optimization unit is for a unicast-use communication route.

13. The packet relay apparatus according to claim 12, wherein

said communication route optimization unit

adds routing information, which is related to an added communication route, to said storage unit in said first stage, and

deletes a transfer identification number and said internal management transfer number or sub internal management transfer number which are related to a communication route becoming redundant from the routing information by changing a setup of at least either one of the internal management transfer number or sub internal management transfer number in said second stage.

14. The packet relay apparatus according to claim 11, wherein

a communication route optimized by said communication route optimization unit is for a multicast-use communication route.

15. The packet relay apparatus according to claim 14, wherein

said communication route optimization unit

adds routing information, which is related to an added communication route, makes said transfer numbers common and forcibly converts said group number in said first stage, and

deletes a transfer identification number and said internal management transfer number or sub internal management transfer number which are related to a communication route becoming redundant from the routing information by changing a setup of at least either one of the internal management transfer number or sub internal management transfer number in said second stage.

16. The packet relay apparatus according to claim 11, wherein

a communication route optimized by said communication route optimization unit is for a broadcast-use communication route.

17. The packet relay apparatus according to claim 16, wherein

said communication route optimization unit

adds routing information, which is related to an added communication route, makes said transfer numbers common and forcibly converts said group number in said first stage, and

changes a setup of at least either one of the internal management transfer number or sub internal management transfer number, and deletes a transfer identification number and said internal management transfer number or sub internal management transfer number which are related to a communication route becoming redundant from the routing information in said second stage.

18. The packet relay apparatus according to claim 7, wherein

said communication route optimization unit switches over between a main route and a sub-route as said second stage when the apparatus itself receives said second IP packet of no less than a specified value from two communication route.

19. The packet relay apparatus according to claim 1, further comprising

a synchronous update unit for monitoring a usage condition of a communication route used by a terminal under the control of the apparatus itself for a communication of said second IP packet, and updating said routing information and route identification information synchronously with another packet relay apparatus placed in the communication route.

20. The packet relay apparatus according to claim 19, wherein

said synchronous update unit carries out said synchronous update when the apparatus itself switches a communication route for said first IP packet from one route over to two routes.

21. The packet relay apparatus according to claim 19, wherein

said synchronous update unit carries out said synchronous update when the apparatus itself switches a communication route for said first IP packet from two routes over to one route.

22. A terminal apparatus communicating an IP packet with a packet relay apparatus connecting a sub-network accommodated by the apparatus itself to a global network, grouping terminals within the sub-network virtually and building up a virtual closed net by inter-group member communication, comprising:

a storage unit which stores routing information, for use in an inter-group member communication, related to a main route, and a sub-route, of a first Internet protocol (IP) packet that is managed by an internal management transfer number for identifying a main route used for the inter-group communication, by a sub internal management transfer number for identifying a sub-route used for the inter-group communication, by a transfer number for identifying a transfer route of the first IP packet which is transferred to another packet relay apparatus and by a group number for identifying a group, and of a second IP packet for processing a transmission and reception within the apparatus itself, and which stores route identification information that is information for identifying an event of being transferred by way of two routes, that is, the main route and sub-route;

an information management unit for setting, and updating, the management information and route identification information stored in the storage unit;

a first packet creation unit for creating the first IP packet by adding the second IP packet, for which a real IP address of the apparatus itself is set as a sender address of an IP header and a virtual IP address of a transmission destination terminal is set as a destination address, and an inter-packet relay apparatus header including information for use between the group member, information related to the main route, the route identification information and a packet identification number for identifying a packet by referring to the routing information stored in the storage unit;

a transmission/reception unit for transmitting the first IP packet created by the first packet creation unit to a packet relay apparatus accommodating the terminal apparatus itself by referring to the routing information and route identification information which are stored in the storage unit and also receiving the first IP packet from the packet relay apparatus; and

a second packet creation unit for by deleting the inter-packet relay apparatus header from the first IP packet received by the transmission/reception unit, followed by creating the second IP packet by referring to the routing information stored in the storage unit.

23. The terminal apparatus according to claim 22, wherein

said transmission/reception unit, comprising a communication unit used for a wired communication and one used for a wireless communication, transmits and receives said first IP packet to and from said packet relay apparatus by utilizing the wired communication-use communication unit and wireless communication-use communication unit.

24. The terminal apparatus according to claim 22, further comprising

a tunnel establishment unit for establishing a tunnel connection to a packet relay apparatus capable of carrying out a routing process utilizing said inter-packer relay apparatus header.

25. The terminal apparatus according to claim 22, wherein

said management information is constituted by

a first table storing a sender identification number assigned to said first terminal and said group number, to which the first terminal belongs, corresponding to a real IP address assigned to a first terminal under the control of the apparatus itself,

a second table storing a destination identification information assigned to a second terminal which is an addressee of said second IP packet transmitted by the first terminal, a group number for a group to which the first terminal belongs, said internal management transfer number and said sub-internal management transfer number,

a third table storing routing information of an IP packet corresponding to the internal management transfer number and storing routing information of the second IP packet corresponding to the sub-internal management transfer number, and

a fourth table managing routing information of the received second IP packet by the internal management transfer number, sub-internal management transfer number and group number.

26. The terminal apparatus according to claim 22, further comprising

a communication route optimization unit for optimizing a communication route for said first IP packet by updating said routing information and route identification information.

27. The terminal apparatus according to claim 22, further comprising

a synchronous update unit for monitoring a usage condition of a communication route used by the apparatus itself for a communication of said first IP packet, and updating said routing information and route identification information synchronously with another packet relay apparatus placed in the communication route.