Advanced, self-balancing video multiplexer system

• US 7,864,808 B2
• Filed: 01/08/2009
• Issued: 01/04/2011
• Est. Priority Date: 08/29/2003
• Status: Active Grant

• Current Assignee: Imagine Communications Limited (Gores Broadcast Holdings LLC)
• Original Assignee: RGB Networks, Inc. (Gores Broadcast Holdings LLC)
• Inventors: Tom, Adam, Monta, Peter, Krause, Edward A.
• Primary Examiner(s): Moe; Aung S
• Assistant Examiner(s): Haile; Feben
• Application Number:
  US12/319,629
• Publication Number:
  US 20090138966A1
• Time in Patent Office: 726 Days
• Field of Search: 370/431, 370/437, 370/464, 370485-487, 725/25, 725/31, 725 86- 87, 725 91- 95, 725104-105, 725/109, 725/111, 725114-117, 725143-147, 709227-229, 380/200, 380/210, 380/212, 713/150, 713/168, 713/176
• US Class Current: 370/486
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 65/1101 Session protocols
• 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: H04L 65/765 intermediate
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04N 19/146 Data rate or code amount at the encoder output
• CPC Class Codes: H04N 19/40 using video transcoding, i.e. partial or full decoding of a coded input stream followed by re-encoding of the decoded output stream
• CPC Class Codes: H04N 19/48 using compressed domain processing techniques other than decoding, e.g. modification of transform coefficients, variable length coding [VLC] data or run-length data motion estimation in a transform domain H04N19/547; processing of decoded motion vectors H04N19/513
• CPC Class Codes: H04N 19/61 in combination with predictive coding
• CPC Class Codes: H04N 21/2225 Local VOD servers
• CPC Class Codes: H04N 21/23103 using load balancing strategies, e.g. by placing or distributing content on different disks, different memories or different servers storage management G06F3/0604; allocation of resources considering the load in multiprogramming arrangements G06F9/505; techniques for rebalancing the load in a distributed system G06F9/5083; access to distributed or replicated servers, e.g. load balancing, in data networks H04L67/1001
• CPC Class Codes: H04N 21/23424 involving splicing one content stream with another content stream, e.g. for inserting or substituting an advertisement
• CPC Class Codes: H04N 21/2347 involving video stream encryption
• CPC Class Codes: H04N 21/23608 Remultiplexing multiplex streams, e.g. involving modifying time stamps or remapping the packet identifiers
• CPC Class Codes: H04N 21/2365 Multiplexing of several video streams
• CPC Class Codes: H04N 21/23655 Statistical multiplexing, e.g. by controlling the encoder to alter its bitrate to optimize the bandwidth utilization
• 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 21/2385 Channel allocation H04N21/266 takes precedence; Bandwidth allocation H04N21/24 takes precedence ; allocation of channels according to the instantaneous demands of the users in time-division multiplex systems H04J3/1682; admission control, resource allocation in open networks H04L12/5692; arrangements for maintenance or administration in data switching networks involving bandwidth and capacity management H04L41/0896; negotiating bandwidth in wireless networks H04W28/16
• CPC Class Codes: H04N 21/2405 Monitoring of the internal components or processes of the server, e.g. server load allocation of resources in multiprogramming arrangements G06F9/50; performance measurement of computer activity G06F11/34
• CPC Class Codes: H04N 21/26216 involving the channel capacity, e.g. network bandwidth admission control, resource allocation in open networks H04L12/5692; flow control in packet networks H04L47/10; establishing a schedule or organising the servicing of application requests taking into account QoS H04L67/61
• CPC Class Codes: H04N 21/26606 : for generating or managing entitlement messages, e.g. Entitlement Control Message [ECM] or Entitlement Management Message [EMM] arrangements for conditional access to broadcast information or to broadcast-related services H04H60/14
• CPC Class Codes: H04N 21/26613 : for generating or managing keys in general key distribution for secret or secure communication involving central third party, e.g. key distribution center [KDC] or trusted third party [TTP] H04L9/083; network support of key management H04L63/06; key management for network security in communication control or processing H04W12/04
• CPC Class Codes: H04N 21/4344 : Remultiplexing of multiplex streams, e.g. by modifying time stamps or remapping the packet identifiers
• CPC Class Codes: H04N 21/4347 : Demultiplexing of several video streams
• CPC Class Codes: H04N 21/44016 : involving splicing one content stream with another content stream, e.g. for substituting a video clip
• CPC Class Codes: H04N 21/47202 : for requesting content on demand, e.g. video on demand
• CPC Class Codes: H04N 21/6118 : involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 21/63345 : by transmitting keys key distribution for secret or secure communication H04L9/08; network support of key management H04L63/06
• CPC Class Codes: H04N 21/812 : involving advertisement data advertising per se G06Q30/02
• CPC Class Codes: H04N 7/1675 : Providing digital key or authorisation information for generation or regeneration of the scrambling sequence pseudo-random number generators in general G06F7/58
• CPC Class Codes: H04N 7/17318 : Direct or substantially direct transmission and handling of requests
• CPC Class Codes: H04N 7/17336 : Handling of requests in head-ends

Abstract

An advanced video multiplexer system designed and optimized for next generation on-demand video distribution is described. The system optimizes identifies a multi-program transport stream best able to accommodate new sessions based upon Quality of Service (QoS) and QAM utilization ratios. MPTS channels are rebalanced via re-grouping and transrating as necessary to optimize bandwidth utilization. Multiple video formats are supported via built-in transcoding. The multiplexer manages encryption resources and supports new sessions using previously allocated encryption resources where possible. Sessions can be grouped into encryption channels either by using a single authorization tier per channel policy, or by requiring all clients of the group to be in physically separated service groups. Encryption channels can be released when a channel no longer serves any clients or when one or more other channels that have been assigned the same entitlement can accommodate any remaining clients.

Claims

1. A method of initializing a client session in a video multiplexer system, comprising:

sending a client session setup request message for specific video program content from a client device to a session manager, said message including a client ID and an asset ID associated with said specific video program content;

determining if the client device is authorized to receive the specific video program content by comparing an entitlement status for the requesting client device with an authorization tier ID associated with an authorization tier for the specific video program content;

sending a session denial message to the requesting client device if the requesting client device is not authorized; and

if the requesting client device is authorized, performing the further steps of;

determining a virtual channel and associated virtual channel ID for providing the requested specific video content to the requesting client device;

assigning a pre-existing encryption channel for the session if the pre-existing encryption channel is compatible with encryption requirements of the session, wherein the encryption requirements comprise a specific set of encryption parameters associated with the authorization tier for the specific video program content, other establishing a new encryption channel for the session; and

sending an entitlement management message (EMM) for the session to the requesting client device; and

sending a session confirmation message including the virtual channel ID to the requesting client device.

2. A method according to claim 1, wherein the video multiplexer system comprises

a session manager;

a plurality of client devices;

a video server responsive to said session manager;

a multiplexer;

encrypter means for encrypting digital video content; and

at least one transrating module.

3. A method in accordance with claim 2, wherein a new client session setup request utilizes the multiplexer and encrypter means used by a preceding session.

4. A method according to claim 1, wherein the step of assigning a pre-existing encryption channel for the session if a compatible pre-existing encryption channel is available comprises:

providing a next available encryption channel to a multiplexer;

determining if session encryption can be accomplished using one or more previously allocated encryption channels;

if session encryption can be accomplished using said one or more previously allocated encryption channels, selecting one of said one or more previously allocated encryption channels for session encryption and obtaining the EMM and identifying information for the selected channel.

5. A method in accordance with claim 1, wherein said establishing of a new encryption channel comprises:

allocating a new encryption channel for session encryption and obtaining the EMM and identifying information for the new channel.

6. A method according to claim 1, further comprising:

providing an entitlement ID associated with the new encryption channel to an encryption manager, wherein the encryption manager assigns identical entitlement keys to encryption channels with identical entitlement IDs.

7. A method according to claim 1, further comprising:

grouping sessions into encryption channels by service group.

8. A method according to claim 1, further comprising:

grouping sessions into encryption channels by authorization tier.

9. A method according to claim 1, wherein a new encryption channel is established if the assignment of a pre-existing encryption channel would result in reduced encryption security.

10. A method according to claim 9, wherein, if a new encryption channel is required but unavailable:

determining whether to allow the session to proceed with a reduced level of security or to send the session denial message to the requesting client device.

11. A method according to claim 1, wherein the client device remains in the same encryption channel when requesting access to new video program content that is associated with a different authorization tier than that of the specific video program content of the session setup request message.

12. A method according to claim 1, further comprising:

transitioning a client device from one encryption channel to another encryption channel when requesting access to new video program content that is associated with a different authorization tier than that of the specific video program content of the session setup request message.

13. A method according to claim 12, further comprising:

changing the entitlement status of the client device.

14. A method according to claim 12, wherein an initial stream of packets of the new video program content is sent in an unencrypted state to allow for a seamless transition between said encryption channels.