摘要:
Methods and apparatuses are provided for detecting traffic patterns in a data network. A sequential hashing scheme can be utilized that has D hash arrays. Each hash array i, wherein 1≦i≦D, includes Mi independent hash tables each having K buckets, with each of the buckets having an associated traffic total. Each of the keys corresponds with a single bucket of each of the Mi independent hash tables of each hash array i. The keys of the data network are partitioned into D words. As traffic is received for a key, a traffic total of each bucket that corresponds with a key is updated. The hash arrays can then be utilized to identify high traffic buckets of the independent hash tables having a traffic total greater than a threshold value. The high traffic buckets can be used to detect significant traffic patterns of the data network.
摘要:
In one embodiment, a method of monitoring a network. The method includes, at each node of a fixed set, constructing a corresponding vector of M components based on data packets received at the node during a time period, M being an integer greater than 1, the fixed set being formed of some nodes of the network; and, based on the constructed vectors, estimating how many of the received data packets have been received by all of the nodes of the set or estimating how many flows of the received data packets have data packets that have passed through all of the nodes of the set. The constructing includes updating a component of the vector of one of the nodes in response to the one of the nodes receiving a data packet. The updating includes selecting the component for updating by hashing a property of the data packet received by the one of the nodes.
摘要:
In one embodiment, a statistical model is generated based on observed data, the observed data being associated with a network device, online parameter fitting is performed on parameters of the statistical model, and for each newly observed data value, a forecast value is generated based on the statistical model, the forecast value being a prediction of a next observed data value, a forecasting error is generated based on the forecast value and the newly observed data value, and whether the data of the network stream is abnormal is determined based on a log likelihood ratio test of the forecasting errors and a threshold value.
摘要:
A capability for incremental tracking of multiples quantiles is provided. A method for performing an incremental quantile update using a data value of a received data record includes determining an initial distribution function, updating the initial distribution function to form a new distribution function based on the received data value, generating an approximation of the new distribution function, and determining new quantile estimates from the approximation of the new distribution function. The initial distribution function includes a plurality of initial quantile estimates and a respective plurality of initial probabilities. The new distribution function includes a plurality of quantile points identifying the respective initial quantile estimates and a respective plurality of new probabilities associated with the initial quantile estimates. The approximation of the new distribution function is generated by connecting pairs of adjacent quantile points using linear approximations of regions between the pairs of adjacent quantile points.
摘要:
A method and apparatus are provided for incrementally tracking quantiles in the presence of multiple record types. A method for performing incremental quantile tracking includes receiving a first data record of a first record type having a first data value, determining whether a second data record of a second record type is received, determining an initial distribution function, updating the initial distribution function to form a new distribution function based on the first data value and whether a second data record is received, generating an approximation of the new distribution function, determining at least one new quantile estimate associated with at least one new probability of the new distribution function using the approximation of the new distribution function, and storing the at least one new quantile estimate and the at least one new probability associated with the at least one new quantile estimate.
摘要:
A method and apparatus are provided for incrementally tracking quantiles in the presence of multiple record types. A method for performing incremental quantile tracking includes receiving a first data record of a first record type and a second data record of a second record type, and updating a quantile probability for a quantile value, based on the first record type of the first data record and the second record type of the second data record, to obtain a new quantile probability for the quantile value.
摘要:
In one embodiment, a method of monitoring a network. The method includes, at each node of a fixed set, constructing a corresponding vector of M components based on data packets received at the node during a time period, M being an integer greater than 1, the fixed set being formed of some nodes of the network; and, based on the constructed vectors, estimating how many of the received data packets have been received by all of the nodes of the set or estimating how many flows of the received data packets have data packets that have passed through all of the nodes of the set. The constructing includes updating a component of the vector of one of the nodes in response to the one of the nodes receiving a data packet. The updating includes selecting the component for updating by hashing a property of the data packet received by the one of the nodes.
摘要:
A method and apparatus for incremental tracking of multiples quantiles is provided. A method for performing an incremental quantile update using a data value of a received data record includes determining an initial distribution function, updating the initial distribution function to form a new distribution function based on the received data value, generating an approximation of the new distribution function, and determining new quantile estimates from the approximation of the new distribution function. The initial distribution function includes a plurality of initial quantile estimates and a respective plurality of initial probabilities. The initial distribution function is updated to form the new distribution function based on the received data value. The new distribution function includes a plurality of quantile points identifying the respective initial quantile estimates and a respective plurality of new probabilities associated with the respective initial quantile estimates. The approximation of the new distribution function is generated by, for each pair of adjacent quantile points in the new distribution function, connecting the adjacent quantile points using a linear approximation of a region between the adjacent quantile points. The new quantile estimates and the new probabilities associated with the new quantile estimates may then be stored.
摘要:
Methods and apparatuses are provided for detecting traffic patterns in a data network. A sequential hashing scheme can be utilized that has D hash arrays. Each hash array i, wherein 1≦i≦D, includes Mi independent hash tables each having K buckets, with each of the buckets having an associated traffic total. Each of the keys corresponds with a single bucket of each of the Mi independent hash tables of each hash array i. The keys of the data network are partitioned into D words. As traffic is received for a key, a traffic total of each bucket that corresponds with a key is updated. The hash arrays can then be utilized to identify high traffic buckets of the independent hash tables having a traffic total greater than a threshold value. The high traffic buckets can be used to detect significant traffic patterns of the data network.
摘要:
There is provided a system and method for estimating network tomography. More specifically, there is provided a computer system configured to measure the transmission delay along a path from a source endpoint of a computer network to a plurality of destination endpoints of the computer network, wherein the path includes at least two data links and wherein at least one of the data links is shared by the plurality of destination endpoints for transmissions from the source endpoint, to calculate a characteristic function of the measured transmission delay, and to calculate a performance parameter of one of the data links based on the characteristic function.