The purpose of SONET is to:

SONET, which stands for Synchronous Optical Network, is primarily designed to transport large amounts of data over fiber optic cables. The main purpose of SONET is to carry multiple T-carrier circuits, such as T1 and T3 lines, through a single fiber optic medium, allowing for efficient bandwidth utilization and greater data transmission capacities.

This system provides a standardized interface for high-speed network communication, helping telecommunications providers manage their networks more effectively. It enables the multiplexing of different data streams into a single signal, ensuring that various types of traffic can coexist without interference.

In contrast, the other options focus on different aspects of data transmission that do not align with SONET’s primary function. For instance, while SONET can support voice data as part of its multiplexing capabilities, it is not solely designed for voice communication over telephone lines. SONET also does not specifically address improvements in wireless communication or secure data transfer across networks, as those fall under different technological solutions. The focus of SONET remains on efficient data transport primarily through fiber optic infrastructure.