For example, data modems often have several status or performance indicators. Analysis of these by technical personnel will often determine the likely cause of failure. Even after corrective action has been taken, DoIT personnel may attempt to repair the defective component so that the problem does not recur. Users should perform self-tests or diagnostics on the end user equipment if those are available. For example, most modem manuals explain the self test procedure for the modem itself.
Most modem equipment has a multilevel diagnostic capability.
It is important that a comprehensive test using these capabilities be done first and the results documented. Commercial Telephone Company Leased Line Diagnosis and Repair Many service problems have historically been traced to the last mile or commercial leased lines. Power outages frequently affect line treatment equipment. For lines leased through outside vendors that connect to microwave service, the user should attempt to determine if the leased line or the microwave service is at fault. If this is the apparent case, please report the leased line to the commercial provider for further testing and repair.