Power control is primarily implemented via purpose-built algorithms. It is implemented on communication devices and systems such as wireless routers, cell phones, cellular networks, sensor networks, DSL modems, etc. Typically, power control allows the transmission or signal power to be scaled, which results in better signal quality. However, power control algorithms are also designed to not scale the power unnecessarily high. Therefore, power control keeps a balance between low, average and high transmission powers for optimal signal or system quality.