Method and system for cable modem initialization using dynamic servers

• US 6,049,826 A
• Filed: 02/04/1998
• Issued: 04/11/2000
• Est. Priority Date: 02/04/1998
• Status: Expired due to Term

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: 3Com Corporation (HP Inc.)
• Inventors: Beser, Nurettin B.
• Primary Examiner(s): Asta, Frank J.
• Assistant Examiner(s): Prieto, Beatriz
• Application Number:
  US09/018,400
• Time in Patent Office: 797 Days
• Field of Search: 709/217, 709/218, 709/219, 709/222, 709/223, 709/224, 709/225, 709/226, 709/203, 709/230, 709/231, 709/335, 380/21-24, 345/335, 364/242, 348/12, 379/93.16, 370/401, 370/402, 370/403, 370/410, 455/3.1, 340/286.02
• US Class Current: 709/222
• CPC Class Codes: G06F 9/4416 Network booting; Remote initial program loading [RIPL]
• CPC Class Codes: H04L 12/2801 Broadband local area networks
• CPC Class Codes: H04L 41/0809 Plug-and-play configuration
• CPC Class Codes: H04L 61/103 across network layers, e.g. resolution of network layer into physical layer addresses or address resolution protocol [ARP]
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]
• CPC Class Codes: H04L 61/5014 using dynamic host configuration protocol [DHCP] or bootstrap protocol [BOOTP]
• CPC Class Codes: H04L 67/06 specially adapted for file transfer, e.g. file transfer protocol [FTP]
• CPC Class Codes: H04L 67/34 involving the movement of software or configuration parameters network booting or remote initial program loading [RIPL] G06F9/4416
• CPC Class Codes: H04L 69/18 Multiprotocol handlers, e.g. single devices capable of handling multiple protocols

Abstract

A method and system for initializing cable modems with dynamic protocol servers is provided. The method and system allow a dynamic protocol server such as a dynamic Trivial File Transfer Protocol ("TFTP") server to override a request for a standard configuration file whose name is supplied to a cable modem in a Dynamic Host Configuration Protocol ("DHCP") response message during initialization. Instead, the dynamic TFTP server identifies a cable modem by performing a reverse Domain Name System lookup of an Internet Protocol address used for the cable modem. Based on the determined identity for the cable modem, the dynamic TFTP server constructs a new configuration file specifically for the cable modem and transfers it to the cable modem. The new configuration file is different from the default configuration file originally requested by the cable modem. Creating a new configuration file with a dynamic protocol server allows greater flexibility for configuring cable modems in a data-over-cable system.

Claims

1. In a data-over-cable system including a plurality of network devices, a method of initializing a network device, the method comprising the following steps:

receiving a first message on a first protocol server with a first protocol from a network device including a request for a first configuration file to configure the network device, wherein the name for the first configuration file was obtained by the network device from a second protocol server using a second protocol during an initialization sequence;

determining an identity for the network device by performing a reverse Domain Name System lookup on a network address from the first message, wherein the identity includes a device type for the network device;

constructing a second configuration file with a plurality of configuration parameters based on a determined identity for the network device; and

transferring the second configuration file to the network device from the first protocol server using the first protocol in response to the request in the first message for the first configuration file, thereby providing a second configuration file specifically for the network device and different from the requested first configuration file.

2. A computer readable medium having stored therein instructions for causing a central processing unit to execute the steps of the method of claim 1.

3. The method of claim 1 wherein the first protocol server is a Trivial File Transfer Protocol server and the second protocol server is a Dynamic Host Configuration Protocol server.

4. The method of claim 1 wherein the Trivial File Transfer Protocol server is a dynamic Trivial File Transfer Protocol server.

5. The method of claim 1 wherein the first protocol is a Trivial File Transfer Protocol and the second protocol is a Dynamic Host Configuration Protocol.

6. The method of claim 1 wherein the network device is a cable modem.

7. The method of claim 1 wherein the step of determining an identity for the network device includes determining a device type for the network device by performing a reverse Domain Name System lookup using an Internet Protocol address from a header field in the first message from the network device.

8. The method of claim 1 wherein the step of constructing a second configuration file with a plurality of configuration parameters based on a determined identity for the network device includes constructing the second configuration file with required standard configuration parameters, and any of optional standard configuration parameters, or vendor-specific configuration parameters.

9. The method of claim 8 wherein the required standard configuration parameters, optional standard configuration parameters and vendor-specific configuration parameters in the second configuration file are encoded in a type-length-value encoding format including two or more message integrity check values used for authentication.

10. The method of claim 1 wherein the second configuration file includes one or more message integrity check values to verify the integrity of the configuration parameters.

11. The method of claim 1 wherein the second configuration file includes one or more configuration parameters not included in the requested first configuration file.

12. In a data-over-cable system including a plurality of network devices, a method of initializing a network device, the method comprising the following steps:

receiving a first message with a first protocol on a first protocol server from a network device including a request for a first configuration file to configure the network device, wherein the name for the first configuration file was obtained by the network device from a second protocol server using a second protocol during an initialization sequence;

determining an identity for the network device by performing a Reverse Domain Name system lookup on a network address from the first message, wherein the identity includes a device type for the network device; and

transferring configuration information dynamically as a data stream to the network device in a pre-determined format based on a determined identity for the network device using the first protocol, wherein the configuration information is dynamically sent as a data stream in response to the request in the first message for the first configuration file and wherein the configuration information sent dynamically as a data system is different form configuration information in the first configuration file.

13. A computer readable medium having stored therein instructions for causing a central processing unit to execute the steps of the method of claim 12.

14. The method of claim 12 wherein the step of determining an identity for the network device includes determining a device type for the network device by performing a reverse Domain Name System lookup on an Internet Protocol address from a header field in the first message from the network device.

15. The method of claim 12 wherein the step of transferring configuration information dynamically as a data stream to the network device in a pre-determined format based on a determined identity for the network device includes transferring required standard configuration parameters and any of optional standard configuration parameters or vendor-specific configuration parameters encoded in a type-length-value encoding format including two or more message integrity check values used for authentication.

16. The method of claim 12 wherein the first protocol server is a dynamic Trivial File Transfer Protocol server.

17. A dynamic protocol server for transferring configuration information for a network device in a data-over-cable system, the dynamic protocol server comprising in combination:

a plurality of network device type identifiers, for identifying a plurality of network device types, wherein a network device identity is obtained by performing a reverse Domain Name System look-up on a network address in a protocol message sent to the dynamic protocol server by a network device requesting a first configuration file, wherein the plurality of network device type identifiers include device types for a plurality of network devices; and

a plurality of configuration information constructors, for dynamically constructing configuration information for initializing a network device based on a device type determined by a network device type identifier, wherein configuration information is constructed from the plurality of configuration information constructors based on a determined network device identity for a network device, thereby providing a second configuration file specifically for the network device and different from a first configuration file originally requested by the network device.

18. The dynamic protocol server of claim 17 wherein the dynamic protocol server is a dynamic Trivial File Transfer Protocol server and the dynamic Trivial File Transfer Protocol server sends a network device a second configuration file or configuration information as a dynamic data stream that is constructed based on a determined identify for the network device instead of a first configuration file requested by the network device.

19. The dynamic protocol server of claim 17 wherein the plurality of network device identifiers determine a device type for a cable modem by performing a reverse Domain Name System lookup on an Internet Protocol address from a header field in a Trivial File Transfer Protocol message.

20. The dynamic protocol server of claim 17 wherein the plurality of configuration information constructors include required standard configuration parameters, and any of optional standard configuration parameters or vendor-specific configuration parameters for initializing a cable modem.

21. In a data-over-cable system including a plurality of cable modems, a method of initializing a cable modem, the method comprising the following steps:

receiving a first Trivial File Transfer Protocol message on a dynamic Trivial File Transfer Protocol server from a cable modem including a request for a first configuration file to configure the cable modem, wherein the name for the first configuration file was obtained by the cable modem from a Dynamic Host Configuration Protocol server using a Dynamic Host Configuration Protocol during an initialization sequence;

determining an identity for the cable modem by performing a reverse Domain Name System lookup on the Internet Protocol address for the cable modem from the first Trivial File Transfer Protocol message, wherein the identity includes a device type for the cable modem;

constructing a second configuration file with a plurality of configuration parameters based on a determined identity for the cable modem; and

transferring the second configuration file to the cable modem from the dynamic Trivial File Protocol server using the Trivial File Protocol in response to the request in the first Trivial File Protocol message for the first configuration file, thereby providing a second configuration file different from the requested first configuration file and specifically for the determined identity of the cable modem.

22. A computer readable medium having stored therein instructions for causing a central processing unit to execute the method of claim 21.