DNS Server, Gateways and Methods for Managing an Identifier of a Port Range in the Transmission of Data

• US 20130013739A1
• Filed: 03/22/2011
• Published: 01/10/2013
• Est. Priority Date: 03/26/2010
• Status: Active Grant

• Current Assignee: Orange S.A.
• Original Assignee: Orange S.A.
• Inventors: Grimault, Jean-Luc, Kassi Lahlou, Mohammed
• Granted Patent: US 9,602,333 B2
• Time in Patent Office: Days
• US Class Current: 709/217
• CPC Class Codes: H04L 2101/663 Transport layer addresses, e.g. aspects of transmission control protocol [TCP] or user datagram protocol [UDP] ports
• CPC Class Codes: H04L 2101/695 using masks or ranges of addresses
• CPC Class Codes: H04L 61/2517 using port numbers
• CPC Class Codes: H04L 61/255 Maintenance or indexing of mapping tables
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]

Abstract

A DNS server (110) and to a method of managing a DNS request, the method comprising a step (E2) of receiving a DNS request for accessing a remote application (104B) accessible via a gateway (106B) and a step (E3) of sending a DNS response including the IP address of the gateway (106B), the method further comprising a verification step for determining whether a port range identifier is stored in the DNS server (110) in association with the IP address of the gateway (106B), and if so, a step of inserting the identifier in the DNS response before sending the DNS response. The invention also provides a method of transmitting data from a first gateway (106A) to a second gateway (106B), a method of transmitting data from a gateway (106B) to a server (102B) of a local network (LAN_B), and the gateways (106A, 106B) for performing such methods.

Claims

1. A method of managing a DNS request carried out by a DNS server, said method comprising:

a step of receiving a DNS request in order to access a remote application accessible via a gateway; and

a step of sending a DNS response including the IP address of said gateway;

a verification step for determining whether a port range identifier is stored in said DNS server in association with the IP address of said gateway; and

if so, a step of inserting said identifier in the DNS response before sending said DNS response.

2. A computer program including instructions for executing steps of the method of managing a DNS request according to claim 1 when said program is executed by a computer.

3. A computer-readable recording medium having recorded thereon a computer program including instructions for executing steps of the method of managing a DNS request according to claim 1.

4. A method of transmitting data in a first gateway to a second gateway, said method comprising:

a preliminary step of storing in the first gateway a port range identifier and the IP address associated with the second gateway to which said data is to be transmitted, said identifier being obtained from a DNS server in response to a DNS request in accordance with the method of claim 1;

a determination step of using said identifier to determine the destination port number to which the data is to be transmitted; and

a step of sending said data to said destination port number of the second gateway.

5. A method according to claim 4, wherein the determination step further comprises:

when a destination port number is initially included in said data, acting during the determination step to determine the destination port number to which the data is to be transmitted from the identifier and from the initial destination port number, and replacing the initial destination port number with said destination port number determined during the determination step;

or

when no destination port number is initially included in said data, encapsulating said data in a data packet including the destination port as determined during said determination step.

6. A method according to claim 4, said method further including transmitting together with said data a source port number determined from a port range identifier associated with the first gateway, said identifier being stored in said first gateway.

7. A computer program including instructions for executing steps of the data transmission method according to claim 4 when said program is executed by a computer.

8. A computer-readable recording medium having recorded thereon a computer program including instructions for executing steps of the data transmission method according to claim 4.

9. A method of transmitting a first data packet from a second gateway to a server of a local network accessible via said second gateway, said first data packet having been transmitted to said second gateway by a first gateway using a method in accordance with claim 4;

said method comprising;

a preliminary step of storing the identifier of a port range associated with said second gateway;

a determination step of using said identifier and a destination port number initially included in the first data packet to determine the destination port number of the server to which said first data packet is to be transmitted; and

a step of sending said first data packet to said destination port number of the server.

10. A method according to claim 9, said method further comprising:

a step of said second server receiving a second data packet sent by the server in response to said first data packet;

a determination step of using said identifier to determine a source port number for transmitting with said second data packet; and

a step of sending the second data packet from said source port number.

11. A computer program including instructions for executing steps of the data transmission method according to claim 9 when said program is executed by a computer.

12. A computer-readable recording medium having recorded thereon a computer program including instructions for executing steps of the data transmission method according to claim 9.

14. A gateway configured to transmit data to a second gateway using a data transmission method in accordance with claim 4, said gateway comprising:

determination means for using a port range identifier associated with the IP address of the second gateway to determine a destination port number to which the data is to be transmitted; and

means for sending said data to said destination port number.

15. A gateway configured to transmit data to a server of a local network accessible via said gateway using a data transmission method in accordance with claim 9, the gateway comprising:

storage means for storing a port range identifier associated with said gateway;

determination means for using said identifier to determine the destination port number of the server to which the data is to be transmitted; and

means for sending said data to said destination port number.

13. A DNS server configured to process a DNS request, said server comprising:

means for receiving a DNS request to access a remote application accessible via a gateway; and

means for sending a DNS response including the IP address of said gateway;

verification means for determining whether a port range identifier is stored in said DNS server in association with the IP address of said gateway; and

insertion means configured to act when the result of said verification is positive to insert said identifier into the DNS response before sending said DNS response.