What is the primary function of a phone modem?

The primary function of a phone modem is to connect telephone lines to digital signals. This process involves converting analog signals from telephone lines into digital signals that can be used by computers and vice versa. By translating the data back and forth between these two formats, the modem enables computers or network devices to transmit and receive data over traditional telephone lines. This functionality is essential for enabling Internet connectivity, especially in scenarios where broadband services such as DSL (Digital Subscriber Line) are utilized, allowing for high-speed internet transmission over existing phone lines.

The other options focus on different functions that are not fundamental to the operation of a phone modem. While wireless access is associated with devices like routers and access points, routing packet data typically pertains to routers that handle data traffic between different networks. Securing a network usually falls under the responsibilities of firewalls or security protocols, rather than the core function of a modem. By outlining these distinctions, it becomes clear why connecting phone lines to digital signals is the primary role of a phone modem.