Part IV. Network Communication
Chapter 27. Serial Communications
Serial Communications
UNIX(R) has always had support for serial communications as the very first UNIX(R) machines relied on serial lines for user input and output. Things have changed a lot from the days when the average terminal consisted of a 10-character-per-second serial printer and a keyboard. This chapter covers some of the ways serial communications can be used on FreeBSD.
After reading this chapter, you will know:
How to connect terminals to a FreeBSD system.
How to use a modem to dial out to remote hosts.
How to allow remote users to login to a FreeBSD system with a modem.
How to boot a FreeBSD system from a serial console.
Before reading this chapter, you should:
Know how to crossref:kernelconfig[kernelconfig, configure and install a custom kernel].
Understand crossref:basics[basics, FreeBSD permissions and processes].
Have access to the technical manual for the serial hardware to be used with FreeBSD.
Serial Terminology and Hardware
The following terms are often used in serial communications:
Bits per Second (bps) is the rate at which data is transmitted.
Data Terminal Equipment (DTE) is one of two endpoints in a serial communication. An example would be a computer.