# Streamer Criterion: Global and local computation

## Local computation

The local computation involves computing the Streamer inception voltage on a path going from a point of the high potential conductor, to arrive at a point of the low potential conductor.

Two path types exist:

- Defined by the electric field line going from the selected starting point
- Defined by a spatial path

Local computation choice in Flux:

## Global computation

For the global computation, user chooses a starting surface and the results give the
path having the highest probality to breakdown (path with the highest **K** value),
with the associated Streamer inception voltage value.

In 2D, a starting surface can be defined by :

- Lines
- Linear regions
- Face regions boundaries

Global computation choice in Flux: