Due to the large number of applications of wide area monitoring systems (WAMSs), many power utilities are implementing phasor measurement units (PMUs)-based WAMS replacing the conventional supervisory control and data acquisition system. The biggest challenge in implementing the technology is the cost of WAMS. Many researchers are trying to minimize the cost of WAMS by making the system observable with optimal placement of PMU. Along with the cost of PMU, the cost of communication infrastructure (CI) is dominating the cost of WAMS. Hence, it is necessary to optimize the communication path link and also to find out the optimal location of phasor data concentrator (PDC). In this paper, an optimization model to find the optimal placement of PMU, optimal location of PDC, and their CI is developed. For this, both independent and simultaneous optimization carried out by using differential evolution algorithm. The multiobjective differential evolution is used for simultaneous optimization. The presence of conventional flow measurement device and its effect on overall cost of WAMS with and without considering presence of optical fiber is presented. The method is implemented with different (N - 1) contingency considerations. Also, the results with the presence of pre-existing PMUs and optical fiber paths are provided.