Proxy addressing scheme for cable networks

• US 7,324,515 B1
• Filed: 03/27/2002
• Issued: 01/29/2008
• Est. Priority Date: 03/27/2002
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Chapman, John T.
• Primary Examiner(s): NGUYEN, BRIAN D
• Application Number:
  US10/109,456
• Time in Patent Office: 2,134 Days
• Field of Search: None
• US Class Current: 370/392
• CPC Class Codes: H04L 12/2801 Broadband local area networks
• CPC Class Codes: H04L 12/4633 Interconnection of networks using encapsulation techniques, e.g. tunneling
• CPC Class Codes: H04L 61/103 across network layers, e.g. resolution of network layer into physical layer addresses or address resolution protocol [ARP]

Abstract

A proxy in a cable modem termination system receives IP packets having an address associated with set top box out of band messages. The proxy encapsulates the packets in an Ethernet frame containing an Ethernet address. A cable modem associated with the set top box is preconfigured to detect the Ethernet encapsulated packets and pass the out of band messages in the packets to the set top box.

Claims

1. A method for transmitting data over a cable network, comprising:

receiving packets having a first address;

using the first address as a proxy address for identifying a second address associated with clients in the cable network;

establishing a tunnel in the cable network by attaching the second address to the packets; and

sending the packets through the tunnel in the cable network to the clients, wherein the sending of the packets comprises sending both Data Over Cable Service Interface Specifications (DOCSIS) IP packets directed to a cable modem and out of band message packets directed to a Set Top Box (STB) over a same channel in the cable network to the same cable modem.

2. A method according to claim 1 including sending the packets to the clients over a one-way cable plant.

3. A method according to claim 1 including using the first and second address for sending packets containing out of band cable messaging to the clients in the cable network.

4. A method according to claim 1 including receiving multicast packets or unicast packets containing the first address.

5. A method according to claim 1 including sending the packets to clients containing set top boxes that operate in a one-way cable network and a two-way cable network.

6. A method for transmitting data over a cable network, comprising:

receiving packets having a first address;

using the first address as a proxy address for identifying a second address associated with clients in the cable network;

establishing a tunnel in the cable network by attaching the second address to the packets;

sending the packets through the tunnel in the cable network to the clients; and

encapsulating the packets by replacing an Ethernet address in the packets with a well-known Ethernet address preconfigured into the clients.

7. A method for transmitting data over a cable network, comprising:

receiving packets having a first address;

identifying different first addresses for packets containing different out of band cable messages;

identifying different Ethernet addresses with the identified different first addresses;

using the identified different first addresses as proxy addresses for identifying the different Ethernet addresses associated with clients in the cable network;

establishing a tunnel in the cable network by attaching the identified different Ethernet addresses to the packets containing different out of band cable messages; and

sending the packets containing different out of band cable messages through the tunnel in the cable network to the clients.

8. A method for transmitting data over a cable network, comprising:

receiving packets having a first address;

using the first address as a proxy address for identifying a second address associated with clients in the cable network by identifying different port numbers associated with the first address;

attaching different Ethernet addresses to the packets associated with the different port numbers;

establishing a tunnel in the cable network by attaching the second address to the packets; and

sending the packets through the tunnel in the cable network to the clients.

9. A cable device, comprising:

a first interface configured to receive packets;

a processor configured to detect packets having an IP proxy address, the processor attaching a second different Ethernet address to the detected packets that is preconfigured into cable clients and allow the packets with the attached second different Ethernet address to be transmitted over a one-way cable system to the cable clients; and

a second interface configured to send the packets with the attached second different Ethernet address over the cable system to the cable clients, wherein the sending of the packets with the attached second different Ethernet address comprises sending both Data Over Cable Service Interface Specifications (DOCSIS) IP packets directed to a cable modem and out of band message packets directed to a Set Top Box (STB) over a same channel in the cable system to the same cable modem.

10. A cable device according to claim 9 wherein the first interlace is coupled to an IP network.

11. A cable device according to claim 10 wherein the first interface receives unicast or multicast packets containing the IP proxy address.

12. A cable device according to claim 9 wherein the processor establishes an Ethernet broadcast pipe in the cable system by encapsulating the detected packets with an Ethernet frame containing the second address.

13. A cable device according to claim 9 including a look-up table that associates different IP proxy addresses with the same or different Ethernet addresses.

14. A cable device, comprising:

a first interface configured to receive packets;

a processor configured to detect packets having an IP proxy address, the processor attaching a second address to the detected packets that allow the IP packets to be transmitted over a one-way cable system to cable clients;

a second interface configured to send the received packets over the cable system to the cable clients; and

a lookup table that contains different port numbers for the IP proxy address and associates the same or different Ethernet addresses with the different port numbers.

15. A cable device, comprising:

a processor configured to detect packets having a first predetermined address and in response to identifying the predetermined address use a second address that is preconifgured into cable modems for transmitting the detected packets over a cable interface to one or more of the cable modems; and

the second address when transmitted in the detected packets causing the one or more cable modems to redirect out of band cable messaging in the detected packets to a Set Top Box (STB).

16. The cable device according to claim 15 wherein the processor sends packets containing the out of band cable messaging directed to the set top box over a Data Over Cable Service Interface Specifications (DOCSIS) channel to the one or more cable modems for forwarding to the set top box and also sends IP packets directed to an IP endpoint over the same DOCSIS channel to the same one or more cable modems.