Abstract
LDT and LDT-P Algorithms are proposed, which fit for linear and parallel service composition respectively .Composition Agent is responsible for searching components and generating a least delay tree. Then candidate paths are found by visiting the tree nodes with the depth-first traversal scheme. At last a path is selected for composed service considering the capability of the nodes and the bandwidth of links comprehensively. Simulation shows LDT and LDT-P Algorithms have the feature of higher composition success ratio and shorter path length, compared with the other current algorithms.