At&t Intellectual Property I, L.p.

At+t Corp.

At&t Labs, Inc.

William Christopher Fenner

Lee Breslau

Kadangode K Ramakrishnan

Divesh Srivastava

Michael Rabinovich

Yin Sheng Zhang

Alexandre Gerber

Charles Robert Kalmanek, Jr

Robert Duncan Doverspike

Subhabrata Bapi Sen

Christopher J Chase

Fragkiskos Papadopoulos

A system includes a processor and a memory. The memory stores instructions that, when executed by the processor, cause the processor to perform operations including sending, via a transmitter, a primary video stream corresponding to a particular channel to a media device. The operations further include sending a secondary video stream to the media device. The secondary video stream is associated with a lower quality level than the primary video stream. Transmission of a frame of the secondary video stream is delayed with respect to transmission of a corresponding frame of the primary video stream.

System and method of providing video content

A method for disseminating content over an overlay network having a plurality of routers in communication with providers and consumers of content is disclosed. A router in the overlay network receives a content descriptor corresponding to a query for content from a node, and generates a subscriber interface list based on the query for the content. The subscriber interface list is transmitted to a plurality of subsequent routers in the overlay network, wherein a content identified by the subsequent routers that correspond to the query will be routed to the router based on the subscriber interface list. The router receives first and second documents corresponding to the query for the content from the node. If the second document is the duplicate, the router deletes the second document and transmits the first document to the node or if not the router transmits both the first and second documents to the node.

Methods and systems for content access and distribution

A system includes a processor and a memory. The memory stores instructions that, when executed by the processor, cause the processor to perform operations including sending a primary multicast video stream and a secondary multicast video stream to a media device. The secondary multicast video stream is limited to intra-coded frames (I-frames) extracted from the primary multicast video stream. Transmission of each intra-coded frame (I-frame) of the secondary multicast video stream is delayed with respect to transmission of a corresponding I-frame of the primary multicast video stream. The delay is based on an amount of writing time to satisfy a buffer threshold of a video content buffer at the media device to prevent a noticeable time shift of video displayed by the media device when the media device switches from outputting the secondary multicast video stream to outputting the primary multicast video stream.

A method and system for monitoring data packet traffic in a multicast network comprising determining a first packet count received at a receiver router, representing a quantity of data packets associated with a multicast group and source at a first time, determining a second packet count received at that receiver router representing a quantity of data packets associated with that multicast group and source, at a second time subsequent to the first time, comparing the second packet count to the first packet count, and indicating an alarm in response to the second packet count being less than a predetermined value greater than the first packet count. A status for multiple routers can be obtained, comprising a difference between the quantity of the first and second packet counts; and indicating a warning in response to at least one of the plurality of router status being less than the predetermined value.

Method and system of monitoring the receipt of multicast traffic

A system and method for receiving, from one or more ingress routers, a first set of records including data corresponding to network traffic, receiving, from one or more egress routers, a second set of records including data corresponding to network traffic and creating a multicast traffic matrix using at least a portion of the data included in the first and second sets of records.

Method and system for computing multicast traffic matrices

A method of providing video content is disclosed that includes receiving video content associated with a television stream from a video source at a server of a video distribution network. The method also includes sending a primary multicast video stream corresponding to the video content to a video distribution network entity via an Internet Protocol (IP) network. The primary multicast video stream is associated with a first bandwidth. Further, the method includes sending a secondary multicast video stream to the video distribution network entity via the IP network. The secondary multicast video stream is associated with a second bandwidth. The primary multicast video stream and the secondary multicast video stream are accessible to a set-top box device via the video distribution network entity in response to a channel change request that indicates the television stream. In addition, the frames of the secondary multicast video stream may be delayed with respect to their counterparts in the primary multicast video stream. This insures that, after sufficient buffering of frames of the primary multicast video stream, when the set-top box device switches from the secondary multicast video stream to the primary multicast video stream there will be no noticeable time shift.

Distribution of content between publishers and consumers is accomplished using an overlay network that may make use of XML language to facilitate content identification. The overlay network includes a plurality of routers that may be in communication with each other and the publishers and consumers on the Internet. Content and queries are identified by content descriptors that are routed from the originator to a nearest router in the overlay network. The nearest router, for each unique content descriptor, generates a hash identification of the content descriptor which is used by remaining routers in the overlay network to provide the appropriate functions with respect to the content descriptor. In particular, this allows all routers in the overlay network except the nearest router to properly route content without processing every content descriptor.

Certain exemplary embodiments provide a method that can comprise establishing a tunnel between a monitor and at least one router; sending a message to join a multicast transmission; and/or transmitting a packet via the tunnel to a router. The packet can comprise a source address of the network monitor and a destination address comprising a multicast address.

Method and apparatus for monitoring a network

A system and method to passively monitor multicast control traffic in the provider backbone. A monitoring station is located within the service provider network. Upon creation of an MVPN session, this monitoring station joins the default multicast distribution tree ('MDT') in the provider backbone used to handle traffic within that MVPN session, and receives the customer's multicast control traffic encapsulated in packets addressed to the default MDT. Using these two kinds of packets, the monitor learns the following information: the identity of the PE routers participating in the MVPN; the identity of the customer multicast groups that are carried on each provider multicast data tree (MDT); the identity of one or more PE routers participating in each customer group, and the identity of the MDT that it is carried on. This information is collected for each customer multicast group, both upstream and downstream at each PE router.

System and method for passively monitoring customer control messages in a multicast VPN

A method of obtaining router information in a multicast network, including transmitting a routing table query and a router name query, receiving router state data associated with a multicast router in response to the routing table query, and receiving a router identifier associated with the multicast router in response to the router name query, the router identifier being distinct from any IP address associated with the multicast router. Also disclosed is a system using a processing device adapted to perform the above method and transmit the router state data to a graphical user interface. The queries are preferably transmitted in Simple Network Management Protocol (SNMP). Further, a part of the displayed data can include hypertext links on router names adapted to display router state data associated with a second multicast router.

Growing community of inventors

Woodside, CA, United States of America

William Christopher Fenner