“…In these approaches, each ant builds a composition solution in each algorithm iteration by starting from the graph origin and by probabilistically choosing candidate services to be added to its partial solution. The probability of choosing a candidate service Roulette-based and elitism selection operator, two point crossover, random mutation [10] Solution: n-tuple QoS, penalty-based Roulette-based selection, uniform and hybrid crossover, random mutation [21] Solution: binary QoS-based Roulette-based selection, one point crossover, random mutation [22] Solution: binary QoS-based Elitism, two-point crossover, random mutation [14] Solution: integer array QoS, semantic, penalty, constraint-based Elitism, multipoint crossover, random mutation [20] Solution: hybrid encoding QoS-based Roulette-based selection, one point crossover, random mutation [2] Solution: hybrid encoding QoS, penalty, customer satisfaction-based Not specified [11] Solution: hybrid encoding QoS-based One point crossover, random mutation depends on the pheromone level associated to the edge in the abstract workflow connecting the current service to the candidate service and on heuristic information. In [23,31], the pheromone reflects the QoS attributes of the candidate service, while in [15] the pheromone is a numerical value equal for each edge connecting two services in the graph of services.…”