Sensing Barrier

The Sensing System Technique is a detection type barrier that can be used to surround an area in a dome, and allows them to monitor said area remotely.

Usage
The barrier itself is twofold in nature: first it create a giant, dome-shaped barrier which surrounds a designated area including the sky above it, as well as below the earth. The sphere has several circles which have the kanji for, and inscribed in them. The barrier is connected to a second, smaller barrier called a at its centre, which the technique's user uses to detect entrants into the barrier as well as maintain the size, and the shape of the barrier. When someone passes through the barrier, the sphere ripples at the point of entry. This sphere is made from water, and persons, or chakra is represented as varying-sized blimps.

This barrier is the one which surrounds Konohagakure and is maintained by the village's barrier team. During the Fourth Shinobi World War, Inoichi Yamanaka and Ao erected this barrier which was used by the Allied Shinobi Forces' Sensor Division to monitor the battle from the headquarters and pass information on to the Intelligence Division.

Countering
According to Pain, Itachi and Kisame were able to enter Konohagakure undetected after Orochimaru's failed invasion because as a former member of Konohagakure's ANBU, Itachi knew how to pass through the barrier surrounding the village undetected.