Fusion of Heterogeneous Intrusion Detection Systems for Network Attack Detection

Table 3

The sample distributions on the training and testing data sets with the corrected labels of NSL-KDD data set.

Class	Training data set		Testing data set
	Number of samples	Samples percentage (%)	Number of samples	Samples percentage (%)	Number of novel attack samples
Normal	13449	53.39	9866	43.76	—
PROBE	2289	9.09	2421	10.74	1315
DOS	9234	36.65	7456	33.07	1715
U2R	11	0.04	67	0.30	32
R2L	208	0.83	2734	12.13	538
	25192	100	22544	100	3600