The idea of ​​duplex is used to name something that is double (that is, it presents the same thing twice or houses a certain quantity twice). The term is used in different contexts.

A duplex is a construction that contains two independent dwellings. These dwellings can be joined in parallel or placed one on top of the other. A duplex, therefore, has more than one floor or story. According to abbreviationfinder, DU stands for Duplex.

Each unit in a duplex has its own door. Beyond the private environments of each family, this type of building usually has common spaces for all the owners, such as a garden or a patio.

“Duplex” is also the title of a film whose story takes place in a house of this class. Directed by Danny De Vito and starring Drew Barrymore and Ben Stiller, it tells the adventures of a couple who have problems living with the neighbor who occupies the top floor of the duplex.

In the field of communications, a system that can receive and send signals simultaneously is known as duplex. In this way, the messages circulate in two directions.

In order for a duplex to develop, it is necessary to have a medium that can carry out transmission in both directions; a system that allows simultaneous receipt and dispatch; and a protocol in the terminal equipment that organizes the communication. In general, all modern systems can work in full duplex since they allow the signals to be received and sent simultaneously.

Depending on whether it is possible to transmit in full or partial duplex mode, we can speak of the following categories of communications:simplex, half duplex and duplex.

Duplex is also called full duplex, and is the most common today, as it allows channels capable of sending and receiving data simultaneously. To achieve this simultaneity, it is possible to use different cables or resort to frequency multiplexing (the use of separate frequencies). Collision-free is expected in full-duplex mode on Ethernet (a local area network standard for computers that defines physical characteristics and data formats).

With regard to half duplex, it is an alternate connection in which the data can only flow in one direction, that is, it does not allow simultaneous reception and sending like the previous one. What benefit can it offer us, being that at first glance it is less “capable” than full duplex? Well, it allows us to take advantage of the line one hundred percent in each transmission, since it does not have to use part of the frequency to send and part to receive.

A very easy to understand example is that of portable transceivers, also known as portable communicators or walkie-talkies, which cannot send and receive data simultaneously: each user must send his message, give the receiver the indication to start sending yours, and wait for the next turn.

Finally we have the simplex, which only offers the possibility of transmitting data in one direction. Although it may seem impractical, there are many cases in which it is not necessary for a system to send and receive information. In addition, its maintenance is easier and its cost is much lower than the other two. Until a few decades ago, fiber optics was perhaps the most common example of simplex, although today it is already possible to take advantage of different wavelengths to achieve duplex communication, something that Internet providers use.

Duplex, finally, is the denomination of a sexual practice that implies the participation of a man and two women. The duplex, in this framework, constitutes a trio.