Thomas Edison invented multiplexing to transmit several telegraph messages over a single line. That was the 19th century, two centuries ago. The technique is still used! Edison was a smart man. He read almost every book in the Detroit Public Library. He invented several thousand products.
spread-spectrum technology
Multicasting
It is possible, whether digital or whether analogic.
56Kbps
Telephones can able to communicate with other telephones through Public Switched Telephone Network, which transmit voice signal over circuit switching technology.
The T-1 channel combines 24x 64 Kbps channels into one single channel using Channel Bonding or Channel Aggregation.
Telephone
microwaves
Ups workers use scanners with technology to transmit date to a terminal
Transmit and receive voice and data communications.
micro wave rays.
Digital Subscribers Line or DSL is a technology that uses telephone lines to transmit high-bandwidth data. Its strengths are independent service, security, integration and cheap line charges.