LapLink cable

A Laplink® Cable, also known as null-printer cable, allows the connection of two computers via the parallel port to establish a direct cable connection.

The cable was introduced in 1983 with the "LapLink" software package, from Traveling Software, to allow fast data transfer between the early PCs running MS-DOS, giving much faster transfer rates than the traditional null modem serial cable. At the time, almost all PCs had a parallel printer port, but neither USB nor modern Ethernet was available.

The INTERSVR program in MS-DOS 6.0 can also use a LapLink cable.

Traveling Software is now known as Laplink Software, Inc. and their main software is now PCmover. With the demise of parallel ports on PCs Laplink no longer sells the traditional cable. Instead it has USB to hard drive, USB to USB and Ethernet to Ethernet cables.

A Laplink® cable can be seen as a parallel equivalent to a serial null modem cable. Because of the higher bandwidth of the parallel port versus the serial port, a Laplink® cable is able to shift data more quickly.

For this reason it was also sometimes used in the past as a means to install Linux to machines without a CD-ROM/DVD drive or Ethernet port built-in; and as a failover link between ha-cluster nodes.

The cable used two DB25 male connectors, and was wired as below:

Laplink® is a registered trademark of Laplink Software, Inc.

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