Wireless sensor systems comprise of individual hubs that can associate with the environment by detecting or controlling physical parameters. These hubs need to team up to satisfy their undertakings. The hubs are interlinked together and by utilizing Wireless connections every hub can convey and team up with each other. In this paper, we center around security issues of WSNs; little overview on the primary difficulties of these systems, a wide assortment of WSNs' assaults and a correlation between them. Our proposed Detection technique detects the congestion and notifies Attacks to the sender before it occurs. Interruption detection (ID) algorithms must be made to work on this partial and localized information. The Data information correspondence to be performed in secure design. Additionally, this paper talks about known methodologies of security identification and defensive mechanism against the connection layer assaults; this would empower IT security chiefs to oversee assaults of WSNs all the more viably.