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This research introduces an active measurement methodology to accurately measure path characteristics crucial for SLA compliance, including mean delay, delay distribution, loss rate, and delay variation. It also presents a new approach to infer lower bounds on delay distribution based on delay measures of selected paths.
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Accurate And Efficient SLA Compliance Monitoring J. Sommers, P. Barford, N. Duffield, A. Ron Presented by Mishari Almishari
Main Contributions • Introduction of a New Active Measurement methodology to measure path characteristics Necessary for SLA • Mean Delay • Delay Distribution • Loss Rate • Delay Variation • New method to infer lower bounds on delay distribution given delay measures of some paths
Active Measurement • Delay • Use Simpson’s method: Aj, bj, Cj • Low error rate • Apply Simpson’s method to a discrete-time probe • Geometric distribution (with pdelay), draw k • Slots I, I +2(k+1), I + (K + 1) • Average estimates
Active Measurement • Distribution Estimation • Sample X1,…Xn • P (Xk <= X) = G(n, F(X), k) • Lower and upper bounds • Delay Variation • DV matrix, Rij/ Sij • Find Eigen Vector, and L1 of E – E’ represents Variance • Loss Rate
Inferring Lower Bounds • Routing Matrix • Scalar additive Model: Xe, Yr • The spanning Set • Using Measures of the spanning paths, we can conclude lower bounds on the delay distribution of other paths • Boundaries..