Abstract :
At this time the many crimes in the internet world that cause the supervision and detection of network security so that it can be anticipated quickly. The purpose of this study provides an analysis of the detection of network attacks located in the LAN labor network informatics engineering of riau Islamic university. So that the need for detection such as snort applications that can detect the presence of a network attack. In this study using penetration test method which is a method that aims to test the system or network security directly located in the informatics engineering labor of riau Islamic university. In this study the use of snort can run well, because snort can detect and send alerts to labor administrators through the social media application telegram and every network attack that occurs in the network LAN snort managed to detect everything in accordance with the rules that have been made.