An apparatus is provided for measuring the performance of a mobile communication system. The apparatus includes two measurement mobile interfaces and a measurement probe. The probe is connected to the backhauling interface of a base station of the system. Then, one measurement mobile interface transmits packets to the other measurement mobile interface via the base station. These packets are received at the base station, forwarded to the packet gateway of the system, sent back to the same base station, and finally received at the destination measurement mobile interface. Since the measurement probe belongs to the same apparatus as the mobile interfaces, it may detect the packets as transmitted/received at the backhauling interface. The probe then generates performance parameters relating to the packets as transmitted/received by the mobile interfaces and/or as detected at the backhauling interface. The system performance is then measured based on such parameters.

A kind of transmission method based on the learnable power model, which conducts periodic record for the historical change trend of the network. This method conducts weighting smooth processing on the round trip time and judges the changing trend of congestion control window. Then, it establishes model for the relationship between network power and the congestion control widow. When a new ACK is received, it immediately updates the window of power model. Finally, it forecasts the size of the congestion control window of the next time period by combining the congestion window and the network power changing trend. For the network packet loss or time-out events, the retransmission mechanism of traditional TCP is used, and when the packet loss ends, the power model process is used again. This invention reduces the influence of the network random events of the estimation error of traditional algorithm.

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for receiving from a plurality of publishers messages of a first channel of a plurality of distinct channels wherein each channel comprises an ordered plurality of messages, storing messages of the first channel in one or more first buffers according to the order, each first buffer having a respective time-to-live, for one or more connections, determining a respective sampling rate based on a data type of the first channel and a determined latency of the connection, receiving from a subscriber through a first connection a request for messages of the first channel, selecting messages in the first buffers according to the order and the sampling rate, and sending the selected messages using the first connection to the subscriber according to the order.

Wireless communications are described. A wireless device may be configured to transmit a first signal via a first cell group that may overlap in time with a second signal via a second cell group. The wireless device may adjust a signal transmission power of at least one of the first signal or the second signal. Additionally or alternatively, the wireless device may drop at least one of the first signal or the second signal. Adjusting and/or dropping at least one of the first signal or the second signal may be based on the overlap in time of these signals satisfying a duration threshold and a total power to transmit the first signal and the second signal exceeding a power threshold.

Technologies for calibrated network interlink access. In some embodiments, a system can calculate a first communication latency of a first link between a first processing element in a first switch and a second processing element in a second switch, and a second communication latency associated with a second link between the first processing element and a third processing element in a third switch. The system can determine a delta between the first communication latency and the second communication latency, and whether respective clock rates of the first switch, second switch, and third switch have a clock rate variation, to yield a clock rate variation determination. Based on the delta and clock rate variation determination, the system can determine an offset value for synchronizing the first communication latency and second communication latency. Based on the offset value, the system can calibrate traffic over the first link and/or the second link.

Techniques for modifying data packet transmission characteristics by an intermediate node in a network are disclosed. An intermediate node in a data transmission network determines a current estimated transmission time for packets being transmitted from the source node to the intermediate node. The node analyzes a data packet to determine a Quality of Service (QoS) requirement for transmission of the first data packet. Based on the current estimated transmission time for packets being transmitted from the source node to the intermediate node and the QoS requirement for transmission of the first data packet, the intermediate node selects one or more transmission characteristics for forwarding the first data packet toward the destination node. The intermediate node transmits the packet toward the destination node in accordance with the one or more transmission characteristics.

Techniques for modifying data packet transmission characteristics by an intermediate node in a network are disclosed. An intermediate node in a data transmission network determines a current estimated transmission time for packets being transmitted from the source node to the intermediate node. The node analyzes a data packet to determine a Quality of Service (QoS) requirement for transmission of the first data packet. Based on the current estimated transmission time for packets being transmitted from the source node to the intermediate node and the QoS requirement for transmission of the first data packet, the intermediate node selects one or more transmission characteristics for forwarding the first data packet toward the destination node. The intermediate node transmits the packet toward the destination node in accordance with the one or more transmission characteristics.

In one embodiment, a system includes a first data communication device including packet processing circuitry to provide a probe packet including an egress timestamp TS1 indicating a time at which the probe packet egresses the first data communication device, and a network interface to send the probe packet via at least one network connection to a second data communication device, and receive from the second data communication device a response packet including the egress timestamp TS1, wherein the packet processing circuitry is configured to associate with the response packet an ingress timestamp TS2 indicating a time at which the response packet ingresses the first data communication device, and a network metric processor to compute a data latency in the at least one network connection responsively to TS1, TS2, and an indication of an internal latency of the probe packet in the second data communication device.

In one embodiment, a system includes a first data communication device including packet processing circuitry to provide a probe packet including an egress timestamp TS1 indicating a time at which the probe packet egresses the first data communication device, and a network interface to send the probe packet via at least one network connection to a second data communication device, and receive from the second data communication device a response packet including the egress timestamp TS1, wherein the packet processing circuitry is configured to associate with the response packet an ingress timestamp TS2 indicating a time at which the response packet ingresses the first data communication device, and a network metric processor to compute a data latency in the at least one network connection responsively to TS1, TS2, and an indication of an internal latency of the probe packet in the second data communication device.

Methods and systems are provided for latency-oriented router. An incoming packet is received on a first interface. The type of the incoming packet is determined. Upon the detection that the incoming packet belongs to latency-critical traffic, the incoming packet is duplicated into one or more copies. Subsequently, the duplicated copies are sent to a second interface in a delayed fashion where the duplicated copies are spread over a time period. The duplicated copies are received and processed at the second interface.