Retransmission-based stream repair and stream join

• US 9,083,585 B2
• Filed: 10/04/2013
• Issued: 07/14/2015
• Est. Priority Date: 09/11/2006
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Oran, David R.
• Primary Examiner(s): Jagannathan, Melanie
• Application Number:
  US14/045,813
• Publication Number:
  US 20140029628A1
• Time in Patent Office: 648 Days
• US Class Current: 1/1
• CPC Class Codes: H04L 1/1607 Details of the supervisory signal
• CPC Class Codes: H04L 2001/0093 Point-to-multipoint
• CPC Class Codes: H04L 45/12 Shortest path evaluation
• CPC Class Codes: H04L 45/16 Multipoint routing
• CPC Class Codes: H04L 61/35 involving non-standard use of addresses for implementing network functionalities, e.g. coding subscription information within the address or functional addressing, i.e. assigning an address to a function
• 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 65/65 Network streaming protocols, e.g. real-time transport protocol [RTP] or real-time control protocol [RTCP]
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04L 67/141 Setup of application sessions admission control or resource allocation in data switching networks H04L47/70
• CPC Class Codes: H04L 69/326 in the transport layer [OSI layer 4] H04L69/16 takes precedence

Abstract

The Real-time Transport Protocol (RTP) and its related standards define a retransmission packet format and a way to give feedback via Negative ACKnowledge (NACK) packets for data that has been lost. In one embodiment, a unicast RTP repair session is associated with a main Source Specific Multicast (SSM) multicast session. Real-time Transport Control Protocol (RTCP) NACK packets are then used for feedback to a SSM feedback target address. This dynamically instantiates unicast RTP repair for multicast sessions. The repair scheme can be used for repairing multicast channels or joining new multicast channels. In another embodiment, a media transmission device shares an IP address with one or more other media transmission devices. The shared IP address can also be used to route multiple identical multicast media streams to different media stream receivers.

Claims

1. One or more non-transitory computer readable storage media encoded with software comprising computer executable instructions and when the software is executed operable to:

receive a channel join request from a media stream receiver;

identify a channel the media stream receiver is joining using a Synchronization SouRCe (SSRCs) in a NACK packet to determine which channel the media stream receiver is joining;

extract the media stream receiver decoder information for a selected media stream;

construct an application specific decoder packet;

send the decoder packet to the media stream receiver;

identify data in a media cache containing a most recent cached intra-coded frame (I-frame); and

send cached packets containing I-frame and subsequent frames up to a current cache time.

2. The one or more non-transitory computer readable storage media encoded with software comprising computer executable instructions of claim 1, wherein the software when executed is further operable to identify the SSRC out of band to the media stream receiver.

3. The one or more non-transitory computer readable storage media encoded with software comprising computer executable instructions of claim 1, wherein the channel join request is a NACK packet containing a Picture Loss Indication.

4. A method comprising:

receiving a channel join request from a media stream receiver;

identifying a channel the media stream receiver is joining using a Synchronization SouRCe (SSRCs) in a NACK packet to determine which channel the media stream receiver is joining;

extracting the media stream receiver decoder information for a selected media stream;

constructing an application specific decoder packet;

sending the decoder packet to the media stream receiver;

identifying data in a media cache containing a most recent cached intra-coded frame (I-frame); and

sending cached packets containing I-frame and subsequent frames up to a current cache time.

5. The method of claim 4, further comprising identifying the SSRC out of band to the media stream receiver.

6. The method of claim 4, wherein receiving the channel join request comprises receiving the channel join request comprising a NACK packet containing a Picture Loss Indication.

7. A system comprising:

a memory storage; and

a processing unit coupled to the memory storage, wherein the processing unit is operative to;

receive a channel join request from a media stream receiver wherein the channel join request is a NACK packet containing a Picture Loss Indication;

identify a channel the media stream receiver is joining;

extract the media stream receiver decoder information for a selected media stream;

construct an application specific decoder packet;

send the decoder packet to the media stream receiver;

identify data in a media cache containing a most recent cached intra-coded frame (I-frame); and

send cached packets containing I-frame and subsequent frames up to a current cache time.

8. The system of claim 7, wherein the processing unit is further operative to use an Synchronization SouRCe (SSRCs) in a NACK packet to determine which channel the media stream receiver is joining.

9. The system of claim 7, wherein the processing unit is further operative to identify the SSRC out of band to the media stream receiver.