Bandwidth optimized rapid channel change in IP-TV network

A method comprising:

• receiving a channel change request from a user terminal in an internet protocol television network, wherein the channel change request indicates a request for packets for a new channel of programming;
• and
• in response to the channel change request, transmitting a unicast stream of packets for the new channel to the user terminal at a full rate of an access link on a path to the user terminal and continuing to transmit the unicast stream of packets at the full rate of the access link beyond an earliest time when the user terminal could join a multicast stream of packets for the new channel, wherein transmitting comprises transmitting the unicast stream of packets with a lower priority quality of service marking than a quality of service marking associated with the multicast stream of packets to cause all of the multicast packets to get through to the user terminal whereas some of the packets for the new channel are dropped and do not get through to the user terminal during a time period beyond the earliest time when the unicast stream is transmitted at the full rate of the access link thereby minimizing a total time duration of a gap in a sequence of packets received by the user terminal as a result of packet collisions between packets from the multicast stream and packets from the unicast stream and packet drops from the unicast stream that occur during the time period.

An apparatus comprising:

• one or more processors;
• memory coupled to the one or more processors, wherein the memory stores instructions executable by the one or more processors and when executed by the one or more processors cause the processors to:
• receive a channel change request from a user terminal in an internet protocol television network, wherein the channel change request indicates a request for packets for a new channel of programming;
• compute a latest time when the user terminal could join a multicast stream based on time of reception of the channel change request;
• and in response to the channel change request, transmit a unicast stream of packets for the new channel to the user terminal at a full rate of an access link on a path to the user terminal and continuing to transmit the unicast stream of packets at the full rate of the access link beyond an earliest time when the user terminal could join the multicast stream of packets for the new channel and until insufficient packets are available for transmission at the full rate at which time packets are transmitted at a rate which is equal to a rate at which new packets are received from a source until the latest time or until reception of a message from the user terminal indicating that the user terminal has joined the multicast stream of packets for the new channel.

An apparatus comprising:

• one or more processors;
• memory coupled to the one or more processors, wherein the memory stores instructions executable by the one or more processors and when executed by the one or more processors cause the processors to:
• receive a channel change request from a user terminal in an internet protocol television network, wherein the channel change request indicates a request for packets for a new channel of programming;
• in response to the channel change request, transmit a unicast stream of packets for the new channel to the user terminal at a full rate of an access link on a path to the user terminal and continuing to transmit the unicast stream of packets at the full rate of the access link beyond an earliest time when the user terminal could join a multicast stream of packets for the new channel;
• wherein the instructions that cause the processor to transmit comprise instructions to transmit the unicast stream of packets with a lower priority quality of service marking than a quality of service marking associated with the multicast stream of packets causing all of the multicast packets to get through to the user terminal whereas some of the packets for the new channel are dropped and do not get through to the user terminal during a time period beyond the earliest time when the unicast stream is transmitted at the full rate of the access link thereby minimizing a total time duration of a gap in a sequence of packets received by the user terminal as a result of packet collisions between packets from the multicast stream and packets from the unicast stream and packet drops from the unicast stream that occur during the time period.

A computer readable memory device storing instructions that, when executed by a processor, are operable to cause the processor to:

• receive a channel change request from a user terminal in an internet protocol television network, wherein the channel change request indicates a request for packets for a new channel of programming;
• in response to the channel change request, transmit a unicast stream of packets for the new channel to the user terminal at a full rate of an access link on a path to the user terminal and continuing to transmit the unicast stream of packets at the full rate of the access link beyond an earliest time when the user terminal could join a multicast stream of packets for the new channel;
• wherein the instructions that cause the processor to transmit the unicast stream comprise instructions that cause the processor to transmit the unicast stream of packets with a lower priority quality of service marking than a quality of service marking associated with the multicast stream of packets causing all of the multicast packets to get through to the user terminal whereas some of the packets for the new channel are dropped and do not get through to the user terminal during a time period beyond the earliest time when the unicast stream is transmitted at the full rate of the access link thereby minimizing a total time duration of a gap in a sequence of packets received by the user terminal as a result of packet collisions between packets from the multicast stream and packets from the unicast stream and packet drops from the unicast stream that occur during the time period.