METHOD FOR THE TRANSMISSION OF DATA PACKETS IN A TUNNEL, CORRESPONDING COMPUTER PROGRAM PRODUCT, STORAGE MEANS AND TUNNEL END-POINT

• US 20090034416A1
• Filed: 07/21/2008
• Published: 02/05/2009
• Est. Priority Date: 07/30/2007
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Rousseau, Pascal, Baron, Stephane
• Granted Patent: US 7,894,364 B2
• Time in Patent Office: Days
• US Class Current: 370/235
• CPC Class Codes: H04L 12/4633 Interconnection of networks using encapsulation techniques, e.g. tunneling
• 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 47/196 Integration of transport layer protocols, e.g. TCP and UDP
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/161 Implementation details of TCP/IP or UDP/IP stack architecture; Specification of modified or new header fields
• CPC Class Codes: H04L 69/164 Adaptation or special uses of UDP protocol
• CPC Class Codes: H04L 69/168 specially adapted for link layer protocols, e.g. asynchronous transfer mode [ATM], synchronous optical network [SONET] or point-to-point protocol [PPP]

Abstract

A method is proposed for the transmission of data packets in a tunnel interconnecting two sub-networks in order to form a general communications network, the tunnel being implemented between two tunnel end-points, each of the sub-networks comprising a distinct tunnel end-point among the tunnel end-points, the tunnel implementing at least two transmission channels, the method being implemented by one of the tunnel end-points, known as a tunnel incoming end-point. The method comprises the following steps for each data packet: reception of the data packet coming from a source device belonging to the same sub-network as the tunnel incoming end-point; selection of an effective channel from among the transmission channels, as a function of a protocol associated with the payload data contained in the received packet, and of a piece of information on quality of transport linked to current conditions of transmission in the transmission channels; encapsulation of the received packet, according to a transport protocol associated with the effective channel, used to obtain a packet to be sent; and transmission of the packet to be sent in the tunnel on the effective channel selected.

Claims

1. A method for the transmission of data packets in a tunnel interconnecting two sub-networks in order to form a total communications network, said tunnel being implemented between two tunnel end-points, each of said sub-networks comprising a distinct tunnel end-point among said tunnel end-points, said tunnel implementing at least two transmission channels, said method being implemented by one of said tunnel end-points, known as a tunnel incoming end-point

wherein the method comprises the following steps for each data packet:

a) reception of said data packet coming from a source device belonging to a same sub-network as the tunnel incoming end-point;

b) selection of an effective channel from among the transmission channels, as a function of a protocol associated with the payload data contained in said received packet, and of a piece of information on quality of transport linked to current conditions of transmission in said transmission channels;

c) encapsulation of said received packet, according to a transport protocol associated with the effective channel, used to obtain a packet to be sent; and

d) transmission of the packet to be sent in the tunnel on the effective channel selected.

2. A method according to claim 1, wherein said information on quality of transport related to current conditions of transmission belongs to the group comprising:

information on congestion of said transmission channels;

information on a packet error rate for said transmission channels; and

information on a retransmission rate of said transmission channels.

3. A method according to claim 1, wherein said step b) of selection of an effective channel comprises the following steps:

i) determining a type of packet associated with said received packet, each type of packet being defined by a distinct protocol associated with the payload data contained in the packets possessing said type of packet;

ii) determining a preferred channel, called a preceding preferred channel enabling, for a previously transmitted packet transmitted by the tunnel incoming end-point and being of a type identical to said received packet, an optimum transmission as a function of a piece of information on quality of transport related to transmission conditions on said transmission channels obtained for said previously transmitted packet;

iii) obtaining said information on quality of transport linked to current conditions of transmission on said transmission channels;

iv) selecting a channel, called a new preferred channel, enabling optimum transmission of said received packet as a function of the type of packet associated with the received packet and of said at least one piece of information on quality of transport linked to current conditions of transmission; and

v) selecting said effective channel as a function of the preceding preferred channel, the new preferred channel and the type of packet associated with said received packet.

4. A method according to claim 3, wherein if, for the type of data associated with said received packet, the preceding preferred channel is different from the new preferred channel, then the selection of the effective channel results from a mechanism of smooth switching from said preceding preferred channel to said new preferred channel for the type of packet associated with said received packet.

5. A method according to claim 1, wherein said step of selection of an effective channel is done from among the following two channels:

a first channel, called a TCP channel, whose associated transport protocol is the TCP protocol; and

a second channel, called a UDP channel, whose associated transport protocol is the UDP protocol.

6. A method according to claim 5, wherein, should the received packet be a UDP type packet, if said information on quality of transport linked to current conditions of transmission indicates a congestion of said transmission channels, then the new preferred channel for said received packet is the UDP channel and, if said information on quality of transport linked to current conditions of transmission does not indicate any congestion of said transmission channels, then the new preferred channel for said received packet is the TCP channel.

7. A method according to claim 5, wherein, should the received packet be a UDP type packet, if said information on quality of transport linked to current conditions of transmission indicates a congestion of said transmission channels, then the new preferred channel of the said received packet is the UDP channel, and if said information on quality of transport linked to current conditions of transmission indicates a packet error rate below a determined threshold, then the new preferred channel for said received packet is the TCP channel and if said information on quality of transport linked to current conditions of transmission indicates a packet error rate of said transmission channels greater than or equal to said determined threshold, then the new preferred channel for said received packet is the UDP channel.

8. A method according to claim 5 wherein, should the received packet be a TCP type packet, if said information on quality of transport linked to current transmission conditions indicate a retransmission rate of said transmission channels above a determined threshold, then the new preferred channel for said received packet is the UDP channel and if said information on quality of transport linked to current conditions of transmission indicate a transmission rate of said transmission channels lower than or equal to said determined threshold, then the new preferred channel for said received packet is the TCP channel.

9. A computer-readable storage medium, storing a computer program comprising a set of instructions executable by a computer in order to implement a method for the transmission of data packets in a tunnel interconnecting two sub-networks in order to form a total communications network, said tunnel being implemented between two tunnel end-points, each of said sub-networks comprising a distinct tunnel end-point among said tunnel end-points, said tunnel implementing at least two transmission channels, said method being implemented by one of said tunnel end-points, known as a tunnel incoming end-point, wherein the method comprises the following steps for each data packet:

a) reception of said data packet coming from a source device belonging to a same sub-network as the tunnel incoming end-point;

b) selection of an effective channel from among the transmission channels, as a function of a protocol associated with the payload data contained in said received packet, and of a piece of information on quality of transport linked to current conditions of transmission in said transmission channels;

c) encapsulation of said received packet, according to a transport protocol associated with the effective channel, used to obtain a packet to be sent; and

d) transmission of the packet to be sent in the tunnel on the effective channel selected.

10. Tunnel incoming end-point enabling the transmission of data packets in a tunnel interconnecting two sub-networks in order to form a total communications network, said tunnel being implemented between said tunnel incoming end-point and a tunnel outgoing end-point, each of said sub-networks comprising a distinct tunnel end-point among said tunnel end-points, said tunnel implementing at least two transmission channels,

wherein it comprises:

means of reception of a data packet coming from a source device belonging to a same sub-network as the tunnel incoming end-point;

means of selection of an effective channel from among the transmission channels, as a function of a protocol associated with the payload data contained in said received packet, and of a piece of information on quality of transport linked to current transmission conditions in said transmission channels;

means of encapsulation of said received packet, according to a transport protocol associated with the effective channel, used to obtain a packet to be sent; and

means of transmission of the packet to be sent in the tunnel on the effective channel selected.

11. A tunnel incoming end-point according to claim 10, wherein said information on quality of transport related to current conditions of transmission belongs to the group comprising:

information on congestion of said transmission channels;

information or a packet error rate for said transmission channels; and

information on a retransmission rate of said transmission channels.

12. A tunnel incoming end-point according to claim 10, wherein said means of selection of an effective channel comprise:

means of determining a type of packet associated with said received packet, each type of packet being defined by a distinct protocol associated with the payload data contained in the packets possessing said type of packet;

means of determining a preferred channel, called a preceding preferred channel enabling, for a previously transmitted packet transmitted by the tunnel incoming end-point and being of a type identical to said received packet, an optimum transmission as a function of a piece of information on quality of transport related to transmission conditions on said transmission channels obtained for said previously transmitted packet;

means of obtaining said information on quality of transport linked to current conditions of transmission on said transmission channels;

means of selecting a channel, called a new preferred channel, enabling optimum transmission of said received packet as a function of the type of packet associated with the received packet and of said at least one piece of information on quality of transport linked to current conditions of transmission; and

means of selection of said effective channel as a function of the preceding preferred channel, the new preferred channel and the type of packet associated with said received packet.

13. A tunnel incoming end-point according to claim 12, wherein said means of selection of the effective channel comprise:

means of implementing a mechanism of smooth switching from said preceding preferred channel to said new preferred channel for the type of packet associated with said received packet; and

means of activation of said means of implementing a smooth switching mechanism if, for the type of packet associated with said received packet, the previous preferred channel is different from the new preferred channel

14. A tunnel incoming end-point according to claim 10, wherein said transmission channels among which the selection of the effective channel is made the following two channels:

a first channel, called a TCP channel, whose associated transport protocol is the TCP protocol; and

a second channel, called a UDP channel, whose associated transport protocol is the UDP protocol.

15. A tunnel incoming end-point according to the claims 14, wherein said means of selection of the effective channel are such that, should the received packet be a UDP type packet, if said information on quality of transport linked to current conditions of transmission indicates a congestion of said transmission channels, then the new preferred channel for said received packet is the UDP channel and, if said information on quality of transport linked to current conditions of transmission does not indicate any congestion of said transmission channels, then the new preferred channel for said received packet is the TCP channel.

16. A tunnel incoming end-point according to the claims 14, wherein said means of selection of the effective channel are such that, should the received packet be a UDP type packet, if said information on quality of transport linked to current conditions of transmission indicates a congestion of said transmission channels, then the new preferred channel of the said received packet is the UDP channel, and if said information on quality of transport linked to current conditions of transmission indicates a packet error rate below a determined threshold, then the new preferred channel for said received packet is the TCP channel and if said information on quality of transport linked to current conditions of transmission indicates a packet error rate of said transmission channels greater than or equal to said determined threshold, then the new preferred channel for said received packet is the UDP channel.

17. A tunnel incoming end-point according to the claim 14, wherein said means of selection of the effective channel are such that, should the received packet be a TCP type packet, if said information on quality of transport linked to current transmission conditions indicate a retransmission rate of said transmission channels above a determined threshold, then the new preferred channel for said received packet is the UDP channel and if said information on quality of transport linked to current conditions of transmission indicate a transmission rate of said transmission channels lower than or equal to said determined threshold, then the new preferred channel for said received packet is the TCP channel.