EFS-DNN: An Ensemble Feature Selection-Based Deep Learning Approach to Network Intrusion Detection System

Table 3

Statistics of KDD 99 and NSL-KDD.

Attack type	KDD 99		NSL-KDD
	Size	Distribution (%)	Size	Distribution (%)
Normal	87832	60.33	67343	53.46
DoS	54572	37.50	45927	36.50
Probe	2131	1.46	11656	9.25
U2R	999	0.69	995	0.79
R2L	52	0.04	52	0.04