A virtual serial port is a

software Software is a set of computer programs and associated documentation and data. This is in contrast to hardware, from which the system is built and which actually performs the work. At the lowest programming level, executable code consists ...

representation of a

serial port In computing, a serial port is a serial communication interface through which information transfers in or out sequentially one bit at a time. This is in contrast to a parallel port, which communicates multiple bits simultaneously in parallel. ...

that either does not connect to a real serial port, or adds functionality to a real serial port through software extension.

Software virtual ports

A software-based virtual serial port presents one or more virtual serial port identifiers on a PC which other applications can see and interact with as if they were real hardware ports, but the data sent and received to these virtual devices is handled by software that manipulates the transmitted and received data to grant greater functionality. Operating systems usually do not provide virtual serial port capability. Third-party applications can add this ability, such as the open-sourc
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HW VSP3
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Virtual Serial Port Driver
Some virtual serial ports emulate all hardware serial port functionality, including all signal pin states, and permit a large number of virtual ports in any desired configuration. Others provide a limited set of capabilities and do not fully emulate the hardware. This technique can be used either to extend the capabilities of software that cannot be updated to use newer communication technologies, such as by transmitting serial data over modern networks, or to achieve data flows that are not normally possible due to software limitations, such as splitting serial port output.

Port sharing

A serial port typically can only be monitored or transmitted to by one device at a time under the constraints of most operating systems, but a virtual serial port program can create two virtual ports, allowing two separate applications to monitor the same data. For instance, a

GPS The Global Positioning System (GPS), originally Navstar GPS, is a Radionavigation-satellite service, satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of t ...

device which outputs location data to a PCs serial port may be of interest to multiple applications at once.

Network transmission

Another option is to communicate with another serial device via internet or LAN as if they were locally connected, using

serial over LAN Serial over LAN (SOL) is a mechanism that enables the input and output of the serial port of a managed system to be redirected over IP. Details On some managed systems, notably blade server systems, the serial ports on the managed computers are ...

. This allows software intended to interface with a device over a local physical serial port to instead communicate at long distance.

Bluetooth

Bluetooth Bluetooth is a short-range wireless technology standard that is used for exchanging data between fixed and mobile devices over short distances and building personal area networks (PANs). In the most widely used mode, transmission power is limi ...

implements virtual serial ports over the

Serial Port Profile In order to use Bluetooth, a device must be compatible with the subset of Bluetooth ''profiles'' (often called services or functions) necessary to use the desired services. A Bluetooth profile is a specification regarding an aspect of Bluetooth-b ...

. This is the standard way of receiving data from Bluetooth-equipped GPS modules, for instance.

Softmodems

The drivers for a software-implemented modem create a virtual serial port for communication with the host operating system, since the modem is implemented entirely in the device driver and therefore there is no point where the serial data would be sent to the physical card.

References

{{reflist Internet Protocol based network software Serial buses Windows communication and services Out-of-band management