Method and apparatus for providing peer-to-peer content delivery

A computer implemented method embodied in a computer program stored in non-transient memory and executed by a computer processor for providing peer to peer content delivery of a live video stream includes delaying delivery of a live stream to a second client to serve that client from a first client that has previously received the live stream. The computer implemented method may further include switching between bad content sources (first clients) to good content sources based on heuristics.

BACKGROUND

The subject matter disclosed herein relates to a method and apparatus for implementing peer to peer content delivery networks. More specifically, the subject matter pertains to a computer implemented method and apparatus for implementing peer to peer content delivery networks by delaying content delivery to facilitate client use of peer content delivery.

Video streaming allows video content to be delivered to a video player via the Internet. The video content is a video signal generated by a content provider for distribution to video consumers. The video signal may be provided in an uncompressed file format, such as a serial digital interface (SDI) format, or in a compressed format, such as a Moving Picture Experts Group (MPEG) file format or Transport Stream (TS) file format. The video signal is sent to an encoder which converts the file into a live streaming signal. The live streaming signal is preferably a segmented data stream that may be transmitted using standard Hypertext Transport Protocol (HTTP) over the internet. The live streaming signal may include multiple streams, where each stream may have a different data rate and/or different resolution.

Two common formats for the live streaming signal include HTTP Live Streaming (HLS) implemented by Apple® and MPEG-Dynamic Adaptive bitrate Streaming over HTTP (MPEG-DASH) implemented, for example, by web browsers such as Chrome®, Microsoft Edge®, and Firefox®. In addition to the segmented data stream, the encoder generates a manifest file. The manifest file contains information for a video player to play the segmented data stream such as the data rate and resolution of each stream and a playlist providing an address from which the video content may be retrieved. Historically, the encoder has generated a single manifest file for each encoded video signal, where the manifest file is distributed along with the streaming signal.

The live streaming signal and the manifest file are stored in one or more Content Delivery Networks (CDN). Each CDN includes a number of edge servers which store the streaming signal and manifest file until requested by a video player. When the streaming signal is provided to multiple CDNs, the CDNs may be in different geographic locations, such as the West Coast, East Coast, or Midwest. Each video player may select a CDN based, among other things, on its geographic proximity in order to reduce transmission latencies.

The video player may be any suitable electronic device to receive the streaming signal such as a desktop computer, a television, a laptop computer, a tablet, or a mobile phone. A user initiates a request to view desired video content on the video player. The video player includes video management software executing on the video player which has knowledge of the address of the CDN and which may provide a list of video content stored on the CDN to the user. After the user has selected a desired video, the video player, in turn, requests that the video content be transmitted from the CDN.

The streaming video content is commonly encrypted prior to transmission. A standard encryption protocol, such as the Advanced Encryption Standard (AES) may be used. During encoding of the video signal, the encoder may communicate with a key server to obtain an encryption key for the video content and encrypt the video signal as part of the encoding process. The encoder may include the location of the encryption key in the manifest file for the encoded video content and provide the manifest file to the CDN. The manifest file is delivered to the video player when the video content is requested. The video player reads the location of the encryption key from the manifest file, retrieves the encryption key, and decrypts the video content on the player prior to displaying the video content to the user.

Live encoders or video on demand encoders generate video segment files and upload them to origin servers or content delivery networks. Content delivery networks distribute these video segments to their edge servers when users submit requests to play the segments. However, it is common in live stream that every edge node and every user attempts to obtain the latest video segments often in temporal proximity. This causes a significant load on a content delivery network's edge servers and can create bottlenecks for video segment delivery.

What is needed is a method of implementing peer to peer content delivery networks to reduce the load on the content delivery networks and edge servers. What is further needed is such a method and apparatus for implementing peer to peer content delivery networks without extensive modification to video player software.

BRIEF DESCRIPTION

The subject matter disclosed herein describes a method for implementing peer to peer content delivery networks for video/media segment delivery by deliberately delaying a second client's live stream to serve that client from a first client that previously downloaded the video/media segment from a traditional content delivery network. The method may include assembling a list of available sources for live video segments and their locations based on previously received segment requests and providing customized manifests identifying those available sources from the list as potential peer content delivery networks.

In one embodiment of the disclosure, a computer implemented method embodied in a computer program stored in non-transient memory and executed by a computer processor for providing peer to peer content delivery of a live video stream includes receiving a first request for video content delivery from a first video player, receiving a second request for the video content delivery from a second video player, providing video content to the first video player from a content delivery network, and providing the video content to the second video player from the first video player.

According to another aspect of the disclosure, providing video content to the first video player from a content delivery network includes providing the video content based on a manifest file identifying the content delivery network as a delivery source. Further, providing video content to the second video player from the first video player includes providing the video content based on a manifest file identifying the first video player as a delivery source.

In another aspect of the disclosure, providing the video content to the second video player from the first video player is delayed for a defined time period. In one another aspect, the defined time period may be at least one video segment length+epsilon.

According to another embodiment of the disclosure, a computer implemented system for providing peer to peer content delivery includes a manifest server operative to generate a unique manifest file per request for a video file stored on a content delivery network. A first unique manifest file for a first video player is configured for providing video content to the first video player from a content delivery network and a second unique manifest file for a second video player is configured for providing video content to the second video player from the first video player.

According to another embodiment of the disclosure, a computer implemented method embodied in a computer program stored in non-transient memory and executed by a computer processor for providing peer to peer content delivery of a live video stream is described. The method includes receiving a first request for video content delivery from a first video player, providing video content to the first video player from a content delivery network, receiving a confirmation of receipt and an indication of availability from the first video player, receiving a second request for the video content delivery from a second video player, and providing the video content to the second video player from the first video player.

In one aspect of the disclosure, the confirmation of receipt and indication of availability are received in the defined time period and the video content is provided from the first video player based on the received confirmation and indication. In another aspect of the disclosure, the confirmation of receipt and indication of availability are received after the defined time period and the video content is provided from the content delivery network.

These and other objects, advantages, and features of the disclosure will become apparent to those skilled in the art from the detailed description and the accompanying drawings. It should be understood, however, that the detailed description and accompanying drawings, while indicating preferred embodiments of the present disclosure, are given by way of illustration and not of limitation. Many changes and modifications may be made within the scope of the present disclosure without departing from the spirit thereof, and the disclosure includes all such modifications.

In describing the preferred embodiments of the disclosure which are illustrated in the drawings, specific terminology will be resorted to for the sake of clarity. However, it is not intended that the disclosure be limited to the specific terms so selected and it is understood that each specific term includes all technical equivalents which operate in a similar manner to accomplish a similar purpose. For example, the word “connected,” “attached,” or terms similar thereto are often used. They are not limited to direct connection but include connection through other elements where such connection is recognized as being equivalent by those skilled in the art.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Turning initially toFIG. 1, an exemplary environment for providing live video stream delivery from a content delivery network using peer to peer content delivery is illustrated. A content provider110generates a video signal112to be distributed to video consumers. The video signal may be provided in an uncompressed file format, such as a SDI format, or in a compressed format, such as an MPEG or TS file format. The video signal112is sent to an encoder114which converts the file into a live streaming signal116. The live streaming signal116is preferably a segmented data stream that may be transmitted using standard HTTP or HTTPS protocol over the internet. The live streaming signal116may include multiple streams, where each stream may have a different data rate and/or different resolution. The format of the live streaming signal may be, but is not limited to, HLS or MPEG-DASH. Still other protocols such as HTTP Dynamic Streaming (HDS) from Adobe® or Microsoft® Smooth Streaming and the like that may be used without deviating from the scope of the disclosure.

In addition to the segmented data stream, the encoder114generates a manifest file. The manifest file contains information for a video player122to play the segmented data stream such as the data rate and resolution of each stream and a playlist providing an address from which the video content may be retrieved. The encoder114generates a single manifest file for each encoded video signal, where the manifest file is distributed along with the streaming signal116to a video origin server131. The manifest files are updated periodically, for example every 10 seconds in one exemplary embodiment, and new segment files are uploaded to the video origin server131. According to an alternative embodiment, the encoder114may be configured to upload manifest files and segment files directly to CDNs118.

CDNs118periodically access video origin server131and upload video segments files such that the video segment files will be stored on one or more CDNs118. The manifest file may include an address of each CDN such that playback may occur from any of the CDNs118. Each CDN118includes a number of edge servers120which store the encoded video signal116and manifest file until playback of the video content is requested by a video player122. Manifest files include two types of playlists, master playlists and rendition playlists.

As further illustrated inFIG. 1, the exemplary environment includes a manifest server124. The manifest server124is used to provide a unique manifest file, also referred to herein as a per-user manifest file, to each video player122for each requested video content. Each video player122includes a native video player module128which provides an interface to a user and which manages video playback on the device122. Some video players122may further include an enhanced video player module129, illustrated as an optional module inFIG. 1. The enhanced video player module129may be a plug-in or other software module executing on the video player122that either complements (i.e., adds additional capabilities) or replaces (i.e., adds additional capabilities and incorporates the video interface and playback capabilities) the native video player module128. As will be discussed in more detail below, when a user requests video content for playback on the video device122, the native or enhanced video player module129communicates with a manifest server124rather than the CDN118to obtain the manifest files for video playback. The manifest server124manages the retrieval and delivery of the manifest file generated by the encoder114to provide the unique manifest file to each video player122.

Turning next toFIG. 2, a flowchart illustrating the operations for implementing live video stream delivery from a content delivery network using peer to peer content delivery is shown, according to the exemplary embodiment. At block130, the encoder114receives the initial video signal112. It is contemplated that this video signal112may be a pre-recorded signal, such as an episode of a television show or a movie, or the video signal112may be a live stream, for example, of a sporting event, concert, or news feed. The encoder114converts the original video signal into a live streaming signal116suitable for delivery via HTTP or HTTPS. One operation in converting the video signal is to divide the video signal into segments. The segments may be, for example, 10 seconds in length. Optionally, other segment lengths, for example, from 1 second up to 10 seconds may be selected. The length of the video segment must be less than the maximum payload for an HTTP data packet.

After converting the video signal112into segments, the encoder114encrypts the video signals112to prevent unauthorized viewing of the video content. At block132, the encoder114establishes communication with a key server126and requests a key to use for encrypting the segmented video signal112. The key server126returns a key to the encoder114as shown in block134. The key used to encrypt the segmented video signal112will be referred to herein as the content encryption key. The encoder114may use any suitable encryption protocol, such as the Advanced Encryption Standard (AES), to encrypt the segmented video signal using the content encryption key. The location of the key server and the encryption key used to encrypt the segmented video signal is included in a manifest file. The manifest file and the encrypted video signal are then transmitted to an origin server131. Manifest files are uploaded periodically and new segment files uploaded to the origin server131for distribution to CDN118. The manifest file and the encrypted video signal may alternatively be uploaded directly from the encoder114to one or more CDN118for storage in one of the edge servers120, as shown in block136. Although the video signal is described herein as being an encrypted video signal, the video signal is not required to be encrypted in alternative embodiments.

Referring now also toFIG. 3, a block diagram representation of an exemplary environment for live video stream delivery from a content delivery network using peer to peer content delivery is shown, according to an exemplary embodiment. At a block138, a first user requests playback of a desired video segment through the video player122. At block140, a second user requests playback of the same desired video segment on a second video player123. The video players122,123may be any suitable electronic devices to receive the streaming signal116such as a desktop computer, a television, a laptop computer, a tablet, Wi-Fi enabled device connected to a video screen, or a mobile phone. As shown in blocks139and141, respectively, the video players122,123request a manifest file from the manifest server124that includes the information needed by the players in order to retrieve the information necessary to play the requested video content.

With reference also toFIGS. 4 and 5, segments of manifest files are illustrated that demonstrate a portion of the content that may be available in a manifest file. The manifest file is a text file and the particular content on each line of the text file is identified by the directive at the start of the line. For example,FIG. 4identifies four different streams in the streaming signal116where each stream has a different bandwidth. The location of a playlist for each of the streams is also included in the manifest file.FIG. 5is another manifest file which contains a portion of the playlist of an encrypted video segment. Each line begins with the location of the key server to decrypt the video segment, identifies a particular video segment between 1 and 5 (i.e., the “−1”, “−2”, etc. . . . prior to the .ts file extension), and provides the location of video segment in the CDN118. The manifest file may include any information corresponding to the video stream, such as metadata information for the video stream.

When the video player122requests the manifest file from the manifest server124a first connection is established between the devices. A session identifier is also generated to identify the connection. The session identifier may be generated by the video player122or the manifest server124. For purposes of illustration, it will be assumed that the session identifier is generated by the video player122. The session identifier is transmitted to the manifest server124by the video player122when requesting a manifest file. The location of a playlist for each of the streams is also included in the manifest file. Each line begins with the location of the key server to decrypt the video segment, identifies a particular video segment between 1 and 5 (i.e., the “−1”, “−2”, etc. . . . prior to the .ts file extension), and provides the location of video segment in the CDN118. The manifest server124then requests the manifest file from the CDN118at block142. At block144, the CDN118returns the manifest file to the manifest server124.

Because the manifest server124has established a connection with video player122, it may customize the manifest file prior to returning the manifest file to the video player122and provide a unique manifest file to each video player122. Without the manifest server124, the video player122retrieves the manifest file directly from the CDN118and the content of the manifest file is the same for all users. However, because the manifest server124is providing a unique manifest file to each player, the manifest file may include identifying information of the video player122, the user of the video player, or a combination thereof. Further, the manifest file may be modified to include content specific for the user. The manifest server124then transmits the manifest file to the video player122, as shown at block145.

The manifest file will have the address of the CDN118as containing the segmented video content. Therefore, the video player can then start retrieving the video content from the CDN118. The video player122repeatedly requests the next segment in the playlist from the CDN118and the CDN returns the requested segment as shown by blocks146and148. The native video player module128then decodes the content from the encrypted video segments and displays the requested video content to the user.

When the second video player123requests the manifest file from the manifest server124a second connection is established. Similar to the first connection, a session identifier is also generated to identify the second connection. The session identifier may be generated by the second video player123or the manifest server124. For purposes of illustration, it will be assumed that the session identifier is generated by the second video player123. The session identifier is transmitted to the manifest server124by the second video player123when requesting a manifest file.

However, in making this second connection, manifest server124has knowledge of the first connection already established with the video player122. Video players122may advertise back to manifest server124(via video HTTP redirect) when the video segment is located and/or available in the video player122. HTTP Redirect method allows the manifest server124to ensure that the video player122has received the previous segment as the video player122is requesting the next segment from CDN118. As soon as this video segment is available, manifest server124can record the change to the video player122's available segments and their statistics, source location, etc. This knowledge may be used to determine whether the video player122is a good candidate to be used as a potential peer content delivery source. Using the video player122's IP address, manifest server124can determine the geolocation of the video player122which may be used to determine which second video players123, for example having a similar geolocation, would benefit from being directed to video player122as a peer content delivery source.

The manifest server124then requests the manifest file from the CDN118at block150and customizes the manifest file for the second connection based on the knowledge regarding the first connection. The customized manifest file may be configured to identify the first player122as the location of the video segments allowing first player122to function as a peer to peer content delivery network. The manifest server124then transmits the customized manifest file to the second video player123, as shown at block153.

The customized manifest file will have the address of the video player122as containing the segmented video content. Therefore, the second video player123can then start retrieving the video content from the video player122as opposed to the CDN118. The second video player123repeatedly requests the next segment in the playlist from the video player122and the video player122returns the requested segment as shown by blocks154and156. The native video player module128then decodes the content from the encrypted video segments and displays the requested video content to the user.

The method and apparatus described above implements peer-to-peer CDN by deliberately delaying a client live stream to serve those clients from peer video segment sources. By leveraging customized manifest delivery, manifest server124may further be configured to switch between bad video sources (bad peer networks) to good video sources (good peer networks) based on heuristics related to devices and/or connections to devices. Further, a customized manifest may be configured to include a plurality of video players122as potential peer content delivery sources. The additional video players122and/or the original CDN118may be configured to function as either primary and/or failover stream sources.

According to an exemplary embodiment, manifest server124may be configured to track delivery of video segments to a large number of video players122. Accordingly, manifest server124will have a record of which video players122have loaded which video segments and their availability such that manifest server124can identify these video players as potential peer content delivery sources.

In order to implement using video players122as peer content delivery sources, during delivery of live video, in which segment requests may be received from a large number of other video players122essentially simultaneously, it may be necessary to delay service to selected video players122, essentially rendering these video players as second video players123, which will receive content from the first video players122. Second video players123may be been delayed for at least one video segment length (TS) plus a small time interval such as one (1) second.

Manifest server124can be configured to include a CDN118as a failover source for each rendition of a manifest file for second video players123. Primary content sources may be the video players122. However, if a second video player123cannot load the video segment from a first video player122, the second video player123will try the failover rendition. Since the failover rendition is also delivered from manifest server124based on the request for failover provision of the video content, manifest server124may note the failure to determine whether the video player122acting as a peer source may have an issue in delivering video segments. These statistics will be tracked during live stream delivery to distinguish bad versus good peer content delivery sources (video players122).

Advantageously, once a video player122has been identified as a live stream source, second video players123will start receiving video segments from the video player122as customized manifest files are distributed. Utilization of this system and method increases the number of available sources, many potentially having better download metrics that a nearest CDN. Further, utilization of the system and method distributes video segment delivery loads across all regions and using video player122resources that may be underutilized to deliver the live video streams.

Portions of the disclosed embodiment are described herein as being implemented on various physical devices, including, but not limited to, a plurality of video players122, second video players123, the manifest server124, the key server126, the encoder114, origin server131, or the edge server120within a CDN118. It would be understood by one skilled in the art that these devices may include processing devices, such as a single microprocessor, multiple microprocessors, co-processors, application specific integrated circuits (ASICs), or other computing devices operating separately, in tandem, or a combination thereof. Further, each of these devices includes storage which may include transitory storage, non-transitory storage, or a combination thereof. The storage may include memory devices such as random access memory (RAM), read-only memory (ROM), solid state memory, and the like. The storage may further include devices configured to read removable storage medium such as CD-ROMs, DVDs, floppy disks, universal serial bus (USB) devices, memory cards, and the like. The processing devices may be configured to read and execute instructions stored in non-transitory storage to perform various operations in the methods described herein.

It should be understood that the disclosure is not limited in its application to the details of construction and arrangements of the components set forth herein. The disclosure is capable of other embodiments and of being practiced or carried out in various ways. Variations and modifications of the foregoing are within the scope of the present disclosure. It also being understood that the technology disclosed and defined herein extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute various alternative aspects of the present disclosure. The embodiments described herein explain the best modes known for practicing the disclosure and will enable others skilled in the art to utilize the disclosure.