Home gateway system for providing optical communication packet data interface function and home broadcast service providing method using the same

• US 20060083253A1
• Filed: 12/29/2004
• Published: 04/20/2006
• Est. Priority Date: 10/15/2004
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Park, Wan Ki, Jeong, Youn Kwae, Choi, Chang Sic
• Granted Patent: US 7,606,228 B2
• Time in Patent Office: Days
• US Class Current: 370/401
• CPC Class Codes: H04L 12/2801 Broadband local area networks
• CPC Class Codes: H04L 12/2856 Access arrangements, e.g. Internet access asynchronous transfer mode networks H04L12/5601; broadband local area networks H04L12/2801; optical access or distribution networks H04Q11/0067; access to open networks H04L12/5691; digital subscriber line end-user equipment and bit-level processing of data on a PSTN-based network H04M11/00; home network gateways H04L12/2834; wireless access networks H04W
• 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: H04L 2101/622 Layer-2 addresses, e.g. medium access control [MAC] addresses
• CPC Class Codes: H04L 61/00 Network arrangements, protocols or services for addressing or naming
• CPC Class Codes: H04L 61/2514 between local and global IP addresses
• CPC Class Codes: H04L 61/2596 Translation of addresses of the same type other than IP, e.g. translation from MAC to MAC addresses

Abstract

There are provided a home gateway system providing an optical communication packet data interface function and a home broadcast service providing method using the same. The home gateway system is constructed to include a network processor having two Ethernet interfaces connected to a system control processor of a home gateway and an Ethernet switch having an Ethernet multicast traffic processing/IGMP snooping function based on an Ethernet L2 multicast MAC table to thereby simultaneously provide a broadcast service such as a CATV broadcast service, and an Internet data service to a plurality of hosts in a home. In case of a broadcast service, the home gateway system converts a broadcast stream into an IP multicast packet and then processes the broadcast IP multicast packet by an L2 multicast function of an Ethernet switch, thereby making it possible to directly transmit the broadcast IP multicast packet to a host without the help of the control processor.

Claims

1. A home gateway system providing an optical communication packet data interface function, the system comprising:

an optical coupler for dividing an optical signal received from an access network into an IP (Internet protocol) network'"'"'s packet data signal and a broadcast network'"'"'s broadcast stream signal;

an ONU (optical network unit) module for packetizing the IP network'"'"'s packet data signal;

a broadcast packet/IP muticast packet module for converting the broadcast network'"'"'s broadcast stream signal into an IP multicast packet;

an Ethernet switch for processing the IP network'"'"'s IP multicast packet and the IP multicast packet into which the broadcast stream is converted according to a L2 multicast MAC (medium access channel) table to then transmit the processed packets to a destination port, and transmitting an unicast packet from the IP network to a control processor; and

the control processor for controlling and managing the unicast packet and the L2 multicast MAC table.

2. The system of claim 1, wherein the broadcast packet/IP multicast packet module comprises:

an O/E (optical/electrical) converter for converting an inputted broadcast stream optical signal into an RF (radio frequency) signal;

a multi-tuner unit for selecting a broadcast channel required to be serviced from a plurality of tuners, and converting the selected broadcast channel into a digital broadcast stream by using a demodulator; and

an IP L2 multicast packet generator for sequentially processing a broadcast signal received from the multi-tuner unit according to a scheduling algorithm to then convert the processed broadcast signal into an IP multicast packet.

3. The system of claim 2, wherein the IP L2 multicast packet generator comprises:

a packet scheduler for sequentially processing a broadcast stream inputted to a multi-structured buffer according to a scheduling algorithm; and

an IP packetization and network interface for converting the broadcast signal received from the packet scheduler into an IP multicast packet and performing interfacing with a gigabit or 10/100 fast interface.

4. The system of claim 1, wherein the Ethernet switch transmits a unicast packet received from the IP WAN (wide area network) to the control processor through a MII (media independent interface) port and transmits a packet processed by the control processor to a corresponding host through a physical device of a destination port.

5. The system of claim 1, wherein the Ethernet switch transmits an IP multicast packet received from the IP WAN to a port to which a host, namely a corresponding multicast group member is connected, by using the L2 multicast MAC table.

6. The system of claim 1, wherein the Ethernet switch transmits a L2 multicast packet of a broadcast stream received from the broadcast WAN port to a port to which a host requesting a broadcast service is connected, by using a MAC table.

7. The system of claim 1, wherein the Ethernet switch provides an IGMP (Internet group management protocol) snooping function and a VLAN (virtual local area network) function.

8. A home broadcast service providing method by using a home gateway system providing an optical communication packet data interface function, the method comprising the steps of:

(a) dividing an optical signal received from an access network into an IP network'"'"'s packet data signal and a broadcast network'"'"'s broadcast stream signal;

(b) transmitting the IP network'"'"' packet data signal to an ONU module and packetizing the IP network'"'"' packet data signal, and then transmitting the packetized IP network'"'"' packet data signal to an Ethernet switch through an IP WAN port of a home gateway;

(c) transmitting the broadcast network'"'"'s broadcast stream signal to a broadcast packet/IP muticast packet module, converting the broadcast network'"'"'s broadcast stream signal into an IP multicast packet, and then transmitting the resulting IP multicast packet to the Ethernet switch;

(d) processing the IP network'"'"'s IP multicast packet and the IP multicast packet into which the broadcast stream signal is converted according to a L2 multicast MAC table to then transmit the processed packets to a destination port, and transmitting an unicast packet received from the IP network to a control processor through a CPU port of the Ethernet switch; and

(e) performing required functions of a control processor, including a NAT/PAT (network address translation/port address translation) function with respect to the unicast packet received from the Ethernet switch, and then retransmitting the resulting packet to the Ethernet switch to then transmit the retransmitted packet to a destination port.

9. The method of claim 8, wherein the step (c) comprises the steps of:

converting an inputted broadcast stream optical signal into an RF signal, selecting a broadcast channel required to be serviced and converting the selected broadcast channel into a digital broadcast stream; and

sequentially processing the broadcast signal according to a scheduling algorithm and converting the processed broadcast signal into an IP multicast packet.

10. The method of claim 8, wherein the step (e) further comprises the step of, if the multicast packet having been transmitted to the destination port is transmitted to a host having a software CODEC (coder and decoder) function, providing a broadcast service by decoding the multicast packet by the software CODEC function, otherwise, if the multicast packet having been transmitted to the destination port is transmitted to a host not having a software CODEC function, providing a broadcast service by an IP set-top function.

11. The method of claim 8, wherein the step of generating and assigning a new broadcast channel when a new host request a new broadcast channel, comprises the steps of:

when the control processor receives an IGMP JOIN message from a port of a L2 Ethernet switch by an IGMP snooping function, checking at the control processor whether a requested channel identifier obtained from the IGMP JOIN message exists in an active channel identifier table;

adding a corresponding port to the active channel identifier table and adding the corresponding port to a L2 multicast MAC table of a L2 switch, if the requested channel identifier exists in the active channel identifier table;

selecting a new multicast address from a multicast address pool if the requested channel identifier does not exist in the active channel identifier table at the third step;

selecting a tuner required to be activated from an IDLE tuner pool;

assigning the requested channel identifier to the selected tuner;

generating a new L2 multicast table in the L2 switch;

informing a newly-activated tuner of a newly-requested channel identifier; and

informing a packet generator of a new channel identifier/multicast address map.

12. The method of claim 8, wherein the step of deleting a currently-serviced broadcast channel comprises the steps of:

when an IGMP LEAVE message is received from a port of a L2 Ethernet switch by an IGMP snooping function or when a control processor recognizes termination of multicast membership recognized through periodic monitoring of IGMP QUERY and IGMP REPORT messages, deleting a requested port from a channel identifier member table;

deleting a requested port from a L2 multicast table;

checking whether another member exists in the channel identifier member table;

judging the result of the checking step;

terminating the step of deleting the currently-serviced broadcast channel without taking any action if another member exists in the channel identifier member table;

returning a corresponding multicast address to a multicast address pool if another member does not exist in the channel identifier member table;

commanding a corresponding tuner to return to an idle state;

commanding a multicast packet generator to delete a corresponding channel identifier/multicast address map; and

returning the corresponding tuner to an idle tuner pool and then terminating the step of deleting the currently-serviced broadcast channel.