VIRTUAL CONVERGED CABLE ACCESS PLATFORMS FOR HFC CABLE NETWORKS

• US 20150172072A1
• Filed: 12/22/2014
• Published: 06/18/2015
• Est. Priority Date: 01/22/2010
• Status: Active Grant

• Current Assignee: Vecima Networks Incorporated
• Original Assignee: Gainspeed Incorporated (Nokia Corporation)
• Inventors: Rakib, Shlomo Selim
• Granted Patent: US 9,887,855 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04B 10/25751 Optical arrangements for CATV or video distribution adaptations of television systems for optical transmission H04N7/22
• CPC Class Codes: H04L 12/2801 Broadband local area networks
• CPC Class Codes: H04L 12/2885 Arrangements interfacing with optical systems optical network equipment H04B10/00; optical multiplexers H04J14/05 and H04J14/07
• CPC Class Codes: H04N 21/23605 Creation or processing of packetized elementary streams [PES]
• CPC Class Codes: H04N 21/2383 Channel coding or modulation of digital bit-stream, e.g. QPSK modulation arrangements for detecting or preventing errors in the information received by adapting the channel coding H04L1/0009; analogue front ends or means for connecting modulators, demodulators or transceivers to a transmission line H04L27/0002
• CPC Class Codes: H04N 21/239 Interfacing the upstream path of the transmission network, e.g. prioritizing client content requests hybrid fiber coaxial [HFC] networks for upstream channel allocation for video distribution H04L12/2801; flow control in data networks H04L47/10; real-time communication protocols in data switching networks H04L65/00; scheduling or organising the servicing of application requests H04L67/60
• CPC Class Codes: H04N 21/6118 involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 21/6125 involving transmission via Internet transmission by internet of broadcast information H04H60/82
• CPC Class Codes: H04N 7/22 Adaptations for optical transmission

Abstract

A virtual converged cable access platform (CCAP) system and method for hybrid fiber CATV (HFC) cable networks. The system uses a new type of digital optical fiber node configured to receive optical fiber data packets, and reconstitute the optical data packets into RF waveforms suitable for injection into the system'"'"'s CATV cable. The system replaces the legacy HFC head end with a simplified “virtual head end”. The system'"'"'s virtual head end operates using a new type of virtual CCAP controller and virtual CCAP software that in turn controls high performance edge routers. Much of the intelligence of running the HFC cable system is managed by the controller software, while the edge router manages the interface between the CATV portion of the system and outside networks. The system can handle even legacy CATV RF signals by appropriate conversion operations, while reducing power and space needs, and improving operational flexibility.

Claims

1. A method of operating an HFC cable network using a virtual converged cable access platform configured to relay data between at least one cable modem and operator server;

said virtual converged cable access platform comprising at least one virtual CCAP controller, at least one edge router, and plurality of digital optical fiber nodes (DOFN), connected to at least one set of neighborhood CATV cables with at least one CATV connected cable modem, said method comprising;

using said DOFN to detect said cable modem, and transmit notification of said cable modem detection via said edge router to said virtual CCAP controller, and using said virtual CCAP controller and said edge router to create and acknowledge said cable modem;

using said virtual CCAP controller and edge router to discover at least one operator server, and further using said DOFN to relay data between said cable modem and said operator servers by way of said edge router and said virtual CCAP controller;

further using said virtual CCAP controller to transmit cable service rules to said edge router, and receive acknowledgement of said service rules from said edge router;

wherein the amount and type of data relayed between said cable modem and said operator servers is controlled by said service rules.

3. The method of claim 1, wherein said virtual CCAP controller is configured to interface with legacy operator servers or systems using at least one of simple network management protocol (SNMP), internet protocol detail record (IPDR), packet cable multimedia (PCMM), Network Configuration Protocol (NETCONF), or command line interface (CLI) protocol.

4. The method of claim 3, wherein said virtual CCAP controller is further configured to manage the process of bringing cable modem and customer premises equipment online to said HFC cable network, and wherein said virtual CCAP controller further implements dynamic host configuration (DHCP) relay and edge router program interface protocols.

5. The method of claim 3, wherein said virtual CCAP controller comprises at least one processor, memory, and virtual CCAP software configured to run on said at least one processor, and to issue commands to said edge router to either:

interface with legacy operator servers or systems using at least one of simple network management protocol (SNMP), internet protocol detail record (IPDR), packet cable multimedia (PCMM), Network Configuration Protocol (NETCONF), or command line interface (CLI) protocol;

or

manage the process of bringing cable modem and customer premises equipment online to said HFC cable network, and to further implement dynamic host configuration (DHCP) relay and edge router program interface protocols.

6. The method of claim 1, wherein said edge router is further configured to handle all level 3+ network layer protocols, including packet forwarding, and routing through intermediate routers.

7. The method of claim 1, wherein said edge router is further configured to implement router control plane addressing including at least one of label distribution protocol (LDP), border gateway protocol (BGP), Intermediate System to Intermediate System (ISIS) protocol, open shortest path first (OSPF) protocol;

and wherein said edge router is further configured to implement at least some level 3 packet processing functions including multiprotocol label switching IP forwarding, subscriber quality of service, packet filters, and virtual local area network (VLAN) manipulation.

8. The method of claim 1, wherein said DOFN is configured to manage a plurality of Cable Radiofrequency and DOCSIS functions, said functions comprising RF modulation, MAC/PHY, Encryption, and Scheduling.

9. The method of claim 1, wherein said at least one edge router is connected to said at least one DOFN by at least one optical fiber.

10. The method of claim 1, wherein said method of operating an HFC cable network further comprises using said virtual CCAP controller and at least one edge router to create a virtual head end;

said HFC cable network further comprises at least a virtual head end connected by at least one optical fiber cable to at least one digital optical fiber node (DOFN) that is connected to at least one set of neighborhood CATV cables, and wherein said data comprises downstream QAM channels;

said method further comprising;

transmitting at least one downstream QAM channel over the optical fiber as a plurality of QAM constellation symbols by encapsulating said QAM constellation symbols into a plurality of Ethernet frames or other digital transmission format frames, and digitally transmitting said plurality of Ethernet frames or other digital transmission format frames over said optical fiber;

using said DOFN to receive said plurality of Ethernet frames or other digital transmission format claims, extract said downstream QAM constellation symbols, and use said downstream video QAM constellation symbols to modulate at least one DOFN QAM modulator, thus producing downstream QAM RF signals, and

transmitting said DOFN generated downstream QAM modulated RF signals further downstream over said at least one set of neighborhood CATV cables.

11. The method of claim 10, wherein said QAM channels comprise either video QAM channels, video Edge-QAM channels, or IP-QAM channels.

12. The method of claim 10, wherein said downstream data further comprises National Television System Committee (NTSC) or Orthogonal Frequency Division Multiplexing (OFDM) RF channels, and further digitally transmitting said data over said optical fiber by:

digitally sampling said NTSC or OFDM RF channels, producing a plurality of digitized waveform data, encapsulating said digitized waveform data into a plurality of digitized waveform data containing Ethernet frames or other digital transmission frames, and digitally transmitting said plurality of digitized waveform data containing Ethernet frames or other digital transmission frames downstream over said optical fiber;

using said DOFN to receive said plurality of digitized waveform data containing Ethernet frames or other digital transmission frames, extract said plurality of digitized waveform data, and use said plurality of digitized waveform data to drive at least one digital to analog converter, thus producing downstream NTSC or OFDM RF channels; and

further transmitting said DOFN generated NTSC or OFDM RF signals further downstream over said at least one set of neighborhood CATV cables.

13. The method of claim 10, wherein said downstream data further comprises Orthogonal Frequency Division Multiplexing (OFDM) RF channels and further digitally transmitting said data over said optical fiber by:

demodulating said OFDM RF channels, producing a plurality of OFDM symbols, encapsulating said plurality of OFDM symbols into a plurality of OFDM symbol carrying Ethernet frames or other digital transmission frames, and digitally transmitting said OFDM symbol carrying Ethernet frames or other digital transmission frames downstream over said optical fiber;

using said DOFN to receive said plurality of OFDM symbol carrying Ethernet frames or other digital transmission frames, extract said plurality of OFDM symbols, and using said plurality of OFDM symbols to drive at least one OFDM RF modulator, thus producing downstream OFDM RF channels; and

further transmitting said DOFN produced OFDM RF signals further downstream over said at least one set of neighborhood CATV cables.

14. The method of claim 10, further used to digitally transmit upstream RF QAM channel data originating from at least one cable modem or other neighborhood CATV cable connected devices, over said optical fiber, by:

at said DOFN, receiving said upstream RF QAM channel data, and demodulating said at least one upstream RF QAM channel into a plurality of upstream QAM constellation symbols;

encapsulating said plurality of upstream QAM constellation symbols into a plurality of Ethernet frames or other digital transmission format frames; and

using said optical fiber to digitally transmit said plurality of Ethernet frames or other digital transmission format frames upstream to said virtual head end.

15. The method of claim 10, further used to digitally transmit upstream RF OFDM channel data, originating from at least one cable modem or other neighborhood CATV cable connected devices, over said optical fiber, by:

at said DOFN, receiving said upstream RF OFDM channel data, and demodulating said at least one upstream RF OFDM channel into a plurality of upstream OFDM symbols;

encapsulating said plurality of upstream OFDM symbols into a plurality of Ethernet frames or other digital transmission format frames; and

using said optical fiber to digitally transmit said plurality of Ethernet frames or other digital transmission format frames to upstream said virtual head end.

16. The method of claim 10, further used to digitally transmit upstream RF channel data, and further digitally transmitting said data over said optical fiber by:

at said DOFN, receiving said upstream RF channel data, digitally sampling said RF channel data producing a plurality of digitized waveform data;

encapsulating said digitized waveform data into a plurality of Ethernet frames or other digital transmission frames; and

using said optical fiber to digitally transmit said plurality of Ethernet frames or other digital transmission frames upstream to said virtual head end.

17. The method of claim 10, used to upgrade a legacy Hybrid Fiber Cable (legacy HFC) system previously configured to transmit data downstream over said optical fiber using analog optical QAM waveforms, said legacy HFC system comprising:

a head end configured to produce downstream RF QAM waveforms;

a legacy fiber optic transmitter system configured to transduce said RF QAM waveforms into downstream analog optical QAM waveforms;

wherein said optical fiber is configured to transmit said analog optical QAM waveforms downstream to at least one legacy optical fiber node;

wherein said at least one legacy optical fiber node is configured to receive said downstream analog optical QAM waveforms, transduce said analog optical QAM waveforms into RF QAM waveforms, and transmit said RF QAM waveforms downstream over said at least one set of neighborhood CATV cables;

said method further comprising;

replacing said head end with said virtual head end;

replacing said at least one legacy optical fiber node with at least one DOFN;

wherein said virtual head end and at least one operator server are configured to transmit at least one downstream RF QAM channel over said optical fiber as a plurality of QAM constellation symbols encapsulated into a plurality of Ethernet frames or other digital transmission format frames using a digital optical transmission method.

2. (canceled)