Method of training and using a computerized system for testing a network that includes computer nodes, to determine functionality of the network, including: determining respective limit values for each of a plurality of data types; obtaining at least one sample of test data of a given data type, converting the sample value into a corresponding normalized sampled value, so that each normalized sampled value is within limit values of the given data type determined based on at least the characteristics of the given data type and the given node; combining normalized values of different types of the given node into a set of combined node features; tagging each set of combined node features with a performance tag; generating a training set that includes a plurality of tagged sets of combined features that pertain to at least one node; and inputting the training set to train the system.