71 results about "Packet prioritization" patented technology

Quality of Service (QoS) support is provided by means of a Tiered Contention Multiple Access (TCMA) distributed medium access protocol that schedules transmission of different types of traffic based on their service quality specifications. In one embodiment, a wireless station is supplied with data from a source having a lower QoS priority QoS(A), such as file transfer data. Another wireless station is supplied with data from a source having a higher QoS priority QoS(B), such as voice and video data. Each wireless station can determine the urgency class of its pending packets according to a scheduling algorithm. For example file transfer data is assigned lower urgency class and voice and video data is assigned higher urgency class. There are several urgency classes which indicate the desired ordering. Pending packets in a given urgency class are transmitted before transmitting packets of a lower urgency class by relying on class-differentiated urgency arbitration times (UATs), which are the idle time intervals required before the random backoff counter is decreased. In another embodiment packets are reclassified in real time with a scheduling algorithm that adjusts the class assigned to packets based on observed performance parameters and according to negotiated QoS-based requirements. Further, for packets assigned the same arbitration time, additional differentiation into more urgency classes is achieved in terms of the contention resolution mechanism employed, thus yielding hybrid packet prioritization methods. An Enhanced DCF Parameter Set is contained in a control packet sent by the AP to the associated stations, which contains class differentiated parameter values necessary to support the TCMA. These parameters can be changed based on different algorithms to support call admission and flow control functions and to meet the requirements of service level agreements.

Quality of Service (QoS) support is provided by means of a Tiered Contention Multiple Access (TCMA) distributed medium access protocol that schedules transmission of different types of traffic based on their service quality specifications. In one embodiment, a wireless station is supplied with data from a source having a lower QoS priority QoS(A), such as file transfer data. Another wireless station is supplied with data from a source having a higher QoS priority QoS(B), such as voice and video data. Each wireless station can determine the urgency class of its pending packets according to a scheduling algorithm. For example file transfer data is assigned lower urgency class and voice and video data is assigned higher urgency class. There are several urgency classes which indicate the desired ordering. Pending packets in a given urgency class are transmitted before transmitting packets of a lower urgency class by relying on class-differentiated urgency arbitration times (UATs), which are the idle time intervals required before the random backoff counter is decreased. In another embodiment packets are reclassified in real time with a scheduling algorithm that adjusts the class assigned to packets based on observed performance parameters and according to negotiated QoS-based requirements. Further, for packets assigned the same arbitration time, additional differentiation into more urgency classes is achieved in terms of the contention resolution mechanism employed, thus yielding hybrid packet prioritization methods. An Enhanced DCF Parameter Set is contained in a control packet sent by the AP to the associated stations, which contains class differentiated parameter values necessary to support the TCMA. These parameters can be changed based on different algorithms to support call admission and flow control functions and to meet the requirements of service level agreements.

The present invention is directed to voice communication devices in which an audio stream is divided into a sequence of individual packets, each of which is routed via pathways that can vary depending on the availability of network resources. All embodiments of the invention rely on an acoustic prioritization agent that assigns a priority value to the packets. The priority value is based on factors such as whether the packet contains voice activity and the degree of acoustic similarity between this packet and adjacent packets in the sequence. A confidence level, associated with the priority value, may also be assigned. In one embodiment, network congestion is reduced by deliberately failing to transmit packets that are judged to be acoustically similar to adjacent packets; the expectation is that, under these circumstances, traditional packet loss concealment algorithms in the receiving device will construct an acceptably accurate replica of the missing packet. In another embodiment, the receiving device can reduce the number of packets stored in its jitter buffer, and therefore the latency of the speech signal, by selectively deleting one or more packets within sustained silences or non-varying speech events. In both embodiments, the ability of the system to drop appropriate packets may be enhanced by taking into account the confidence levels associated with the priority assessments.

A switch fabric includes input links, output links, and at least one switching element. The input links are configured to receive data items that include destination addresses. At least some of the data items have different priority levels. The output links are configured to output the data items. Each of the output links is assigned multiple ones of the destination addresses. Each of the destination addresses corresponds to one of the priority levels. The switching element(s) is / are configured to receive the data items from the input links and send the data items to ones of the output links without regard to the priority levels of the data items.

A switch fabric includes input links, output links, and at least one switching element. The input links are configured to receive data items that include destination addresses. At least some of the data items have different priority levels. The output links are configured to output the data items. Each of the output links is assigned multiple ones of the destination addresses. Each of the destination addresses corresponds to one of the priority levels. The switching element(s) is / are configured to receive the data items from the input links and send the data items to ones of the output links without regard to the priority levels of the data items.

The present invention is directed to voice communication devices in which an audio stream is divided into a sequence of individual packets, each of which is routed via pathways that can vary depending on the availability of network resources. All embodiments of the invention rely on an acoustic prioritization agent that assigns a priority value to the packets. The priority value is based on factors such as whether the packet contains voice activity and the degree of acoustic similarity between this packet and adjacent packets in the sequence. A confidence level, associated with the priority value, may also be assigned. In one embodiment, network congestion is reduced by deliberately failing to transmit packets that are judged to be acoustically similar to adjacent packets; the expectation is that, under these circumstances, traditional packet loss concealment algorithms in the receiving device will construct an acceptably accurate replica of the missing packet. In another embodiment, the receiving device can reduce the number of packets stored in its jitter buffer, and therefore the latency of the speech signal, by selectively deleting one or more packets within sustained silences or non-varying speech events. In both embodiments, the ability of the system to drop appropriate packets may be enhanced by taking into account the confidence levels associated with the priority assessments.

The present invention is directed to voice communication devices in which an audio stream is divided into a sequence of individual packets, each of which is routed via pathways that can vary depending on the availability of network resources. All embodiments of the invention rely on an acoustic prioritization agent that assigns a priority value to the packets. The priority value is based on factors such as whether the packet contains voice activity and the degree of acoustic similarity between this packet and adjacent packets in the sequence. A confidence level, associated with the priority value, may also be assigned. In one embodiment, network congestion is reduced by deliberately failing to transmit packets that are judged to be acoustically similar to adjacent packets; the expectation is that, under these circumstances, traditional packet loss concealment algorithms in the receiving device will construct an acceptably accurate replica of the missing packet. In another embodiment, the receiving device can reduce the number of packets stored in its jitter buffer, and therefore the latency of the speech signal, by selectively deleting one or more packets within sustained silences or non-varying speech events. In both embodiments, the ability of the system to drop appropriate packets may be enhanced by taking into account the confidence levels associated with the priority assessments.

A packet scheduler includes a packet manager interface, a policer, a congestion manager, a scheduler, and a virtual output queue (VOQ) handler. The policer assigns a priority to each packet. Depending on congestion levels, the congestion manager determines whether to send a packet based on the packet's priority assigned by the policer. The scheduler schedules packets in accordance with configured rates for virtual connections and group shapers. A scheduled packet is queued at a virtual output queue (VOQ) by the VOQ handler. In one embodiment, the VOQ handler sends signals to a packet manager (through the packet manager interface) to instruct the packet manager to transmit packets in a scheduled order.

The invention discloses a long distance CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance) protocol with QoS (Quality of Service) assurance, a node in a communication channel executes the following steps: (1) entering a backoff stage after sending of the previous data packet is finished in a sending queue; (2) according to priority conditions of the data packets in the existing sending queue, extracting the data packet with the highest priority and arranging the extracted data packet at the head of the sending queue; (3) calculating a channel busy-to-idle ratio and a priority threshold corresponding to the data packet of the head of the sending queue; (4) after the backoff stage is ended, detecting the busy-to-idle ratio of the current channel, and comparing the priority threshold corresponding to the data packet of the head of the sending queue with the busy-to-idle ratio of the current channel, if the busy-to-idle ratio of the current channel is less than the priority threshold corresponding to the data packet, enabling the data packet to be accessed to the channel and sending the data packet, and returning back to the step (1). According to the long distance CSMA / CA protocol with QoS assurance provided by the invention, performance requirement of the data packet with high priority is satisfied through delay of access of the data packet with low priority, and hereby, a collision probability is reduced and a throughput is improved.