Traffic measurement should make it possible to obtain the spatial flow of traffic through the domain, i.e., the paths or trajectories followed by packets between any ingress and egress point of the domain. A method of sampling packet trajectories in a packet switching network allows the direct inference of traffic flows through a measurement domain by observing the trajectories of a subset of all packets traversing the network. A method which assumes that the measurement domain does not change comprises the steps of selecting packets for sampling in accordance with a sampling function of the packet content and generating a practically unique label for each sampled packet. The method does not rely on routing state, its implementation cost is small, and the measurement reporting traffic is modest and can be controlled precisely. Using the same hash function will yield the same sample set of packets in the entire domain, and enables us to reconstruct packet trajectories. An alternate embodiment which assumes no constraints and that the measurement domain may change comprises the steps of applying a sampling function and altering an invariant bit position as a signaling flag in each packet selected for sampling.
A method for sampling n-out-of-N packets in a network. Initially, the packet index corresponding to the N packets is pseudo-randomly shuffled. The shuffle function rearranges a set of numbers pseudo-randomly with a one-to-one mapping and no overlap. One way to perform the pseudo-random shuffle function is to use a linear feedback shift register (LFSR). The LFSR supports N being a power of two. However, the LFSR approach can be adapted to support N being any positive integer value. Based on the results of the shuffle function, sampling points are pseudo-randomly selected. By pseudo-randomly selecting the sample points, n-out-of-N sampling greatly minimizes biases.
A method of calculating data traffic flow in a communications network, the communications network comprising a plurality of nodes including a plurality of source nodes and a plurality of destination nodes, the nodes being connected to one another by links, the method comprising: (a) obtaining data traffic flow measurements through said nodes and links as input data; (b) correcting said input data if inconsistencies are detected; (c) calculating upper and lower bounds of data traffic flow from a selected one of the plurality of source nodes to a selected one of the plurality of destination nodes using the corrected input data.
Traffic measurement should make it possible to obtain the spatial flow of traffic through the domain, i.e., the paths or trajectories followed by packets between any ingress and egress point of the domain. A method of sampling packet trajectories in a packet switching network allows the direct inference of traffic flows through a measurement domain by observing the trajectories of a subset of all packets traversing the network. A method which assumes that the measurement domain does not change comprises the steps of selecting packets for sampling in accordance with a sampling function of the packet content and generating a practically unique label for each sampled packet. The method does not rely on routing state, its implementation cost is small, and the measurement reporting traffic is modest and can be controlled precisely. Using the same hash function will yield the same sample set of packets in the entire domain, and enables us to reconstruct packet trajectories. An alternate embodiment which assumes no constraints and that the measurement domain may change comprises the steps of applying a sampling function and altering an invariant bit position as a signaling flag in each packet selected for sampling.
A technique for autonomous network provisioning based on establishing a relation between network performance indices, traffic measurements and resource capacities, which provides automatic provisioning recommendations for identified critical links is disclosed. The technique may be implemented in a network through collaboration across node controllers and network controllers. A method for the autonomous provisioning of a network, wherein a plurality of nodes of the network collaborate to determine required additional resources, may comprise the steps of receiving at least one network-state measurement comprising at least one of a traffic measurement and a performance measurement; determining at least one critical link based at least in part on the at least one network-state measurement; and formulating at least one link provisioning recommendation for the at least one critical link.