According to what was defined in the Network Procedures Sub-Module 2.2, it is up to ONS to annually perform the overstress analysisa short circuit equipment, load current, time constant (X / R) and other types of request. Such analyzes are intended to ensure the safety of the operation, as identified in advance of three years the possible cases of network overstress. This information is forwarded to MME for permission to replace the equipment or overcome the adoption of mitigating measures.