Method for assigning an IP address to a device

• US 7,483,396 B2
• Filed: 01/20/2005
• Issued: 01/27/2009
• Est. Priority Date: 01/23/2004
• Status: Active Grant

• Current Assignee: Siemens AG
• Original Assignee: Siemens AG
• Inventors: Steindl, Gunter
• Primary Examiner(s): HSU, ALPUS
• Application Number:
  US11/039,614
• Publication Number:
  US 20050163118A1
• Time in Patent Office: 1,468 Days
• Field of Search: 370/254, 370/389, 370/401, 709/203, 709/220, 709/229
• US Class Current: 370/254
• CPC Class Codes: H04L 61/5014 using dynamic host configuration protocol [DHCP] or bootstrap protocol [BOOTP]
• CPC Class Codes: H04L 61/5038 for local use, e.g. in LAN or USB networks, or in a controller area network [CAN]
• CPC Class Codes: Y02D 30/00 Reducing energy consumption in communication networks

Abstract

The invention relates to a method for assigning an IP address to a device (116), comprising the following steps:

• • connecting the device (116) to a port (110) of a switch (104),
  • transmitting an identification code (124) of the port (110) from the switch (104) to the device (116),
  • transmitting the identification code (124) of the port (110) from the device (116) to an address server (122),
  • assigning the IP address to the device (116) on the basis of the identification code (124) of the port (110).

Claims

1. A method for assigning an Internet Protocol (IP) address to a client device connected to a data communications switch on a network, comprising:

connecting a given client device to a port on the switch for data communication between the given client device and the switch;

the switch sensing the connection of the given client device to the port, and the switch then automatically transmitting an identification code of the port (port ID) to the given client device;

the given client device receiving the port ID from the switch, and the given client device then automatically transmitting the received port ID in a request to an address server via the switch without filtering of the request in the switch;

the address server receiving the port ID from the given client device, and the address server then automatically assigning an unambiguous IP address to the given client device, wherein the assigning is initiated by the given client device transmitting the request to the address server, and wherein the port ID is used by the address server as a basis for assigning the IP address.

2. The method of claim 1, wherein the given client device is an industrial automation device comprising a sensor, a drive, or a controller.

3. The method of claim 1, wherein the port ID is automatically transmitted from the switch to the given client device using a neighbor discovery protocol.

4. The method of claim 3, wherein request is transmitted by the client device to the address server in accordance with a Dynamic Host Configuration Protocol (DHCP), in which the assigning of the IP address to the given client device is initiated by the given client device itself, and not in response to a polling by the address server.

5. The method of claim 4, further comprising additional client devices on respective ports on the network, wherein each of the client devices, upon activation, receives a respective port identification code from the respective port, and then each client device automatically sends a DHCP request containing the respective port identification code to the address server, which then automatically assigns a unique IP address to each client device in a reply to each client device, wherein the switch does not filter the DHCP requests from the client devices to the address server.

6. The method of claim 5, wherein the neighbor discovery protocol automatically provides network topology information, comprising the port identification code for each respective port, to the address server, and the address server stores the network topology information, and uses it to assign the unique IP address to each requesting client device.

7. The method of claim 1, wherein successive client devices successively use the port, and the address server assigns the same IP address to each successive client device on the port, based on the port ID.

8. The method of claim 7, wherein the steps of claim 7 are performed automatically upon replacement of a faulty client device on the port with a replacement client device, wherein an IP address assigned by the address server to the replacement client device is the same as a previously assigned IP address of the faulty client device, based on the same port ID used by both the faulty client device and the replacement client device.

9. The method of claim 8, wherein the faulty client device and the replacement client device are each an industrial automation device comprising a sensor, a drive, or a controller.