IP broadcasting system and a multicast group management apparatus for the same

• US 8,522,288 B2
• Filed: 07/17/2007
• Issued: 08/27/2013
• Est. Priority Date: 12/20/2006
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Ikeda, Hiroki, Sakamoto, Kenichi, Shinagawa, Taishi
• Primary Examiner(s): Srivastava, Vivek
• Assistant Examiner(s): Le, Rong
• Application Number:
  US11/778,969
• Publication Number:
  US 20080155612A1
• Time in Patent Office: 2,233 Days
• Field of Search: 725114-117
• US Class Current: 725/86
• CPC Class Codes: H04L 12/185 with management of multicast group membership
• CPC Class Codes: H04L 12/1877 Measures taken prior to transmission
• CPC Class Codes: H04L 65/611 for multicast or broadcast systems for broadcast or conference H04L12/18; arrangements for broadcast or distribution combined with broadcast H04H20/00; arrangements for broadcast applications with a direct linkage to broadcast information or to broadcast space-time H04H60/00; selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS], H04W4/06
• CPC Class Codes: H04N 21/4384 involving operations to reduce the access time, e.g. fast-tuning for reducing channel switching latency
• CPC Class Codes: H04N 21/6125 involving transmission via Internet transmission by internet of broadcast information H04H60/82
• CPC Class Codes: H04N 21/6405 Multicasting data broadcast and multicast in packet switching networks H04L12/18
• CPC Class Codes: H04N 21/643 Communication protocols network streaming protocols, e.g. real-time transport protocol [RTP] or real-time control protocol [RTCP], H04L65/65
• CPC Class Codes: H04N 21/64322 IP

Abstract

The present invention provides an IP broadcasting system that can receive IP broadcasting videos over an IP multicast network. In the IP broadcasting system, a multicast group management apparatus for IP broadcasting that holds multicast group identifiers is connected via an IP multicast network over which IP broadcasting services are provided. When a user issues a request to switch an IP broadcasting channel from an IP broadcasting terminal, a query message including the requested IP broadcasting channel identifier is transmitted to a management apparatus. The IP broadcasting terminal receives a response message indicating the correspondence between the IP broadcasting channel identifier and a multicast group identifier, and transmits a video reception request message to a multicast group by using the received multicast group identifier.

Claims

1. An IP broadcasting system that provides IP broadcasting services over an IP multicast network, the IP broadcasting system comprising:

an IP broadcasting server that distributes video data by adding a multicast group identifier;

an IP broadcasting terminal that transmits an IP broadcasting channel identifier;

a multicast group management apparatus for IP broadcasting that allocates the multicast group identifier to the IP broadcasting channel identifier and includes a storing unit that holds correspondence information between the multicast group identifiers and the IP broadcasting channel identifiers; and

a data transfer device disposed between the IP broadcasting terminal and the multicast network for transmitting a video distribution request message,

wherein the IP broadcasting terminal includes a transmitting/receiving unit that transmits a query message including the requested IP broadcasting channel identifier to the multicast group management apparatus for IP broadcasting, receives a response message including the multicast group identifier corresponding to the IP broadcasting channel identifier included in the query message, the response message being transmitted from the multicast group management apparatus for IP broadcasting, and transmits a video reception request message by using the received multicast group identifier, and

wherein the data transfer device includes a transmitting unit that receives the multicast group identifier corresponding to video data information, which is held by the data transfer device, from a multicast group management apparatus for IP broadcasting on the IP multicast network, that manages correspondence information between the multicast group identifier and the video data information, and transmits a video distribution request message including the received multicast group identifier to the IP multicast network, prior to receiving a video reception request message from the IP broadcasting terminal;

a receiving unit that receives video data, to which the multicast group identifier included in the video distribution request message is assigned, transmitted from the IP multicast network based on the video distribution request message; and

a transfer unit that, when receiving the video reception request message from the IF broadcasting terminal, transmits the receiving video data corresponding to the video reception request message to the IP broadcasting terminal.

2. The IP broadcasting system according to claim 1,

wherein:

the multicast group management apparatus for IP broadcasting holds a list of the multicast group identifiers in the storing unit; and

based on a request to allocate the multicast group identifier from the IP broadcasting server, the multicast group management apparatus for IP broadcasting refers to the list to decide the multicast group identifier, and transmits it to the IP broadcasting server.

3. The IP broadcasting system according to claim 1,

wherein the multicast group management apparatus for IP broadcasting holds a multicast address as the multicast group identifier.

4. The IP broadcasting system according to claim 1,

wherein the multicast group management apparatus for IP broadcasting holds a combination of a multicast address and a source address as the multicast group identifier.

5. The IP broadcasting system according to claim 2,

wherein:

the list comprises a multicast address pool list; and

the IP broadcasting system holds correspondence information between the multicast group identifiers and area information.

6. The IP broadcasting system according to claim 2,

wherein:

the list comprises a multicast address pool list; and

the IP broadcasting system holds correspondence information between the multicast group identifiers and distribution priority within the IP multicast network.

7. A set-top box that connects an IP broadcasting terminal via an IP multicast network to an IP broadcasting server that distributes video data by adding a multicast address, the set-top box comprising:

a transmitting unit that receives the multicast address corresponding to video data information, which is held by the set-top box, from a multicast group management apparatus for IP broadcasting on the IP multicast network, that manages correspondence information between the multicast address and the video data information, and transmits a video distribution request message including the received multicast address to the IP multicast network, prior to receiving a video reception request message from the IP broadcasting terminal;

a receiving unit that receives video data, to which the multicast address included in the video distribution request message is assigned, transmitted from the IP multicast network based on the video distribution request message; and

a transfer unit that, when receiving the video reception request message from the IP broadcasting terminal, transmits the received video data corresponding to the video reception request message to the IP broadcasting terminal.

8. The set-top box according to claim 7, further comprising:

a storing unit that holds correspondence information between an IP broadcasting channel identifier as the video data information and the multicast address.

9. The set-top box according to claim 8,

wherein, on receiving a query message including the IP broadcasting channel identifier from the IP broadcasting terminal, the processing unit searches the correspondence information stored in the storing unit, and when the corresponding multicast address does not exist, inquires of the multicast group management apparatus for IP broadcasting.