## 3 Evaluation of Melt Test Parameters and Analysis of DSL Service Provision
### Algorithm of Evaluation of MELT Test Parameters and Analysis of Quantities  
The algorithm of evaluation for MEST test parameters is based on comparing the value of a particular evaluated quantity with a specified value. First, the value of quantities is determined by DSL service demands, standard homogeneous symmetric line requirements and expert discussion. This value is prepared within the algorithm for comparison with the acquired measured value of quantities. Second, a GOOD/WARNING/FAIL message statement is performed based on this comparison. Finally, the overall evaluation of the homogeneous symmetric line is subsequently based on the PASS and FAIL message statement. This extract serves for the overall parameter evaluation of the tested homogeneous symmetric line. The structure of the mobile application consists of the main screen, where a list of nine quantities (three quantities, each tested on three sections) is prepared, to which values of quantities can be entered. After entering them, the evaluation of MELT test parameters and analysis of quantities starts. There is a button called Evaluate in the right corner. After pressing it, an overall evaluation of line parameters and analysis of specific quantities is performed.  
Figure 2 illustrates the structure of the comparison involving the ranges of evaluated parameters and analyzed quantities. As can be seen, the allowed ranges and permitted tolerances for DC foreign voltages, specifically for DC foreign voltages between Ring -Ground (RG), are defined and realized in Lines 102-123. A condition for the allowed range corresponding to Row 1 in Table 1 is realized and evaluated in Lines 103-106, where two text messages are considered. For this condition, the main text message (GOOD) is green colored and the second text message comments closely on the evaluation result. Subsequently, conditions for the permitted tolerances corresponding to Rows 2-4 in Table 1  
are defined and evaluated in Lines 108-123. For these conditions, the main text message is yellow (WARNING) or red (FAIL) colored and the second text messages comment closely on appropriate evaluation results. Because the total number of quantities is nine, they must be analyzed in an appropriate and corresponding way in this program.  
As mentioned above, three quantities (DC foreign voltage, AC foreign voltage and C capacity) are evaluated and analyzed for three distinct types of sections (RG, TR and TG). The algorithm consists of comparing the value of a particular evaluated quantity with the range defined in the application according to Table 1. The evaluation process begins by loading the measured value of a quantity from the homogeneous symmetric line. After entering the measured values of all relevant quantities, the evaluation process starts in the mobile application. This consists of a statement of reports evaluating quantities and reports that analyze these quantities.  
The structure of the MELT test parameter evaluation shall include:  
* Text messages--GOOD (quantity in the allowed range), WARNING (quantity in permitted tolerances) or FAIL (out of the allowed range and permitted tolerances).
* Comments on the evaluated measured values of quantities and on possible causes of the failure (in the case of the range excess).  
The resulting evaluation consists of the PASS text message if most of the parameters meet the specified criteria or the FAIL text message if several line parameters are above or below the range. Since no literature or other resources explicitly specify how the overall evaluation of the MELT test parameters should be conducted, it has been defined that at least half of the evaluated values of quantities must meet the criteria for a favorable evaluation of the MELT test parameters.