System and method for a specialized dynamic host configuration protocol proxy in a data-over-cable network

• US 6,952,428 B1
• Filed: 01/26/2001
• Issued: 10/04/2005
• Est. Priority Date: 01/26/2001
• Status: Expired due to Term

• Current Assignee: Valtrus Innovations Limited (f/k/a Dolya Holdco 9 Limited) (Key Patent Innovations Limited)
• Original Assignee: 3Com Corporation (HP Inc.)
• Inventors: Necka, William, Fey, Igor, Akgun, Ali, Arutyunov, Yuri
• Primary Examiner(s): Phunkulh, Bob
• Assistant Examiner(s): Moore, Ian N.
• Application Number:
  US09/772,095
• Time in Patent Office: 1,712 Days
• Field of Search: 370/401, 370/352, 370/475, 370/474, 370/351, 370/353, 370/354, 370/355, 370/466, 709/229, 709238-242, 709/245, 709/220, 709/227, 709/218, 725/9, 725110-117
• US Class Current: 370/466
• CPC Class Codes: H04L 41/0869 Validating the configuration within one network element
• CPC Class Codes: H04L 61/5014 using dynamic host configuration protocol [DHCP] or bootstrap protocol [BOOTP]
• CPC Class Codes: H04L 61/5053 Lease time; Renewal aspects
• CPC Class Codes: H04L 61/59 using proxies for addressing

Abstract

A system and method for proxying Dynamic Host Configuration Protocol (“DHCP”) network services for a network device, such as, a customer premise equipment entity, on a network device, such as, a cable modem, include creating a specialized proxy task for the customer premise equipment entity on the cable modem. One method of the present invention includes intercepting DHCP message flow between a customer premise equipment having a specialized proxy task created on the cable modem and a DHCP server selected by the customer premise equipment entity. The methods further include modifying lease time intervals prior to providing a routable network address lease to a customer premise equipment entity and renewing an initial lease for the customer premise equipment entity by a cable modem prior to expiration of the lease time interval provided by a DHCP server. The methods include using known protocols, such as, for example, the Dynamic Host Configuration Protocol.

Claims

1. In a data-over-cable system, a method for proxying first protocol network services, the method comprising:

creating a database record comprising identification data of a second network device and identification data of a first protocol network server selected by the second network device;

intercepting at a first network device a first protocol offer message from the first protocol network server to the second network device;

wherein the first protocol offer message comprises a routable network address for the second network device and a lease time interval for the routable network address;

modifying the lease time interval in the first protocol offer message intercepted on the first network device;

sending the modified first protocol offer message from the first network device to the second network device;

receiving a first protocol request message on the first network device from the second network device prior to an end of the modified lease time interval provided to the second network device, the first protocol request message defining a lease renewal request for the routable network address associated with the second network device;

intercepting the first protocol request message on the first network device prior to the first protocol network server receiving the first protocol request message;

generating a first protocol response message on the first network device using the identification data of the first protocol network server, the lease time interval provided in the first protocol offer message and the modified lease time interval; and

sending the first protocol response message to the second network device.

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

3. The method as claimed in claim 1, wherein the first protocol network services comprise Dynamic Host Configuration network services.

4. The method as claimed in claim 1, further comprising, storing the lease time interval received in the first protocol offer message and the modified lease time interval in the database record associated with the second network device.

5. The method as claimed in claim 1, wherein the first network device comprises a cable modem, the second network device comprises a customer premise equipment entity and the first protocol network server comprises a Dynamic Host Configuration Protocol server.

6. The method as claimed in claim 1, wherein the first protocol offer message comprises a Dynamic Host Configuration Protocol Offer message.

7. The method as claimed in claim 1, wherein the first protocol response message comprises a Dynamic Host Configuration Protocol message.

8. The method as claimed in claim 1, further comprising, specifying a remaining lease time interval in the first protocol response message, wherein the remaining lease time interval is determined using the lease time interval specified in the first protocol offer message and further using the modified lease time interval.

9. The method as claimed in claim 1, further comprising:

determining whether the second network device is not using the routable network address; and

if so,

using the routable network address of the second network device on the first network device.

10. In a data-over-cable system, a method for proxying first protocol network services, the method comprising:

creating a database record comprising identification data of a second network device and identification data of a first protocol network server selected by the second network device;

intercepting at a first network device a first protocol offer message from the first protocol network server to the second network device;

wherein the first protocol offer message comprises a routable network address for the second network device and a lease time interval for the routable network address;

modifying the lease time interval in the first protocol offer message intercepted on the first network device;

sending the modified first protocol offer message from the first network device to the second network device;

generating a first protocol request message on the first network device using the identification data of the second network device the first protocol request message defining a lease renewal request for the routable network address of the second network device;

sending the first protocol request message from the first network device to the first protocol network server prior to an expiration of the lease time interval specified in the first protocol offer message received from the first protocol network server; and

receiving a first protocol reply message from the first protocol network server, the first protocol reply message defining a new lease time interval for the routable network address of the second network device.

11. In a data-over-cable system, a method for proxying first protocol network services, the method comprising:

creating a database record comprising identification data of a second network device and identification data of a first protocol network server associated with the second network device;

intercepting at a first network device a first protocol offer message from the first protocol network server to the second network device, the first protocol offer message comprising a routable network address for the second network device and a first lease time interval associated with the routable network address;

modifying the lease time interval defined in the first protocol offer message, wherein the lease time interval is modified to a shorter lease time interval;

sending the modified first protocol offer message to the second network device;

generating a first protocol request message on the first network device using the identification data of the second network device, the first protocol request message comprising a lease renewal request for the routable network address associated with the second network device; and

sending the first protocol request message to the first protocol network server prior to an end of the lease time interval specified in the first protocol offer message;

receiving a first protocol response message from the first protocol network server, the first protocol response message defining a new lease time interval for the routable network address associated with the second network device;

intercepting the first protocol request message from the second network device, the first protocol request message defining a lease renewal request;

generating the first protocol response message on the first network device using the identification data of the first protocol network server, the first protocol response message defining a second lease time interval, wherein the second lease time interval comprises a shortened lease time interval defined in the first protocol response message received from the first protocol network server; and

sending the first protocol response message generated on the first network device to the second network device.

12. A computer readable medium having stored therein instructions for causing a central processing unit to execute the method of claim 11.

13. The method as claimed in claim 11, wherein the first network device comprises a cable modem, the second network device comprises a customer premise equipment entity and the first protocol network server comprises a Dynamic Host Configuration Protocol network server.

14. The method as claimed in claim 11, wherein the first protocol offer message comprises a Dynamic Host Configuration Protocol Offer message, and the first protocol request message comprises a Dynamic Host Configuration Protocol Request message.

15. The method as claimed in claim 11, wherein the first protocol response message from the first protocol network server comprises a Dynamic Host Configuration Protocol Offer message, the first protocol request message comprises a Dynamic Host Configuration Protocol Request message and the first protocol response message generated on the first network device comprises a Dynamic Host Configuration Protocol Offer message.

16. A system for proxying first protocol network services in a data-over-cable system, the system comprising:

a database comprising a record for a second network device in communication with a first network device, the record comprising identification data of the second network device and identification data of a first protocol network server selected by the second network device; and

the first network device intercepting first protocol messages between the second network device and the first protocol network server associated with the second network device, the first network device modifying a first protocol offer message from the first protocol network server, wherein the first network device modifies a lease time interval of a routable network address for the second network device and sends the modified first protocol offer message to the second network device,

wherein the first network device uses the identification data of the first protocol network server, the lease time interval specified in the first protocol offer message and the modified lease time interval to generate a first protocol response message for the second network device upon intercepting a first protocol lease renewal request message from the second network device, the second network device sending the first protocol lease renewal request message upon an end of the modified lease time interval.

17. The system as claimed in claim 16, wherein the first network device uses the identification data associated with the second network device to generate a first protocol lease renewal request message and sends the first protocol lease renewal message prior to an end of the lease time interval specified in the first protocol offer message.

18. The system as claimed in claim 16, wherein the first network device stores the lease time interval specified in the first protocol offer message and the modified lease time interval in the record of the second network device.

19. The system as claimed in claim 16, wherein the first network device sends the generated first protocol response message to the second network device.

20. The system as claimed in claim 16, wherein the first network device specifies a remaining lease time interval in the first protocol response message.

21. The system as claimed in claim 16, wherein the first network device comprises a cable modem, the second network device comprises a customer premise equipment entity and the first protocol network server comprises a Dynamic Host Configuration Protocol network server.

22. The system as claimed in claim 17, wherein the first protocol messages comprise Dynamic Host Configuration Protocol messages.