Communications Parameters - Toshiba Satellite 110 Series User Manual

160
Connecting with the World
The Internet and Other Fascinating Places

Communications Parameters

There are four communications parameters:
Modem speed is the speed at which the modem transfers infor-
mation. Speeds are measured in bits per second. Your modem
manual documents the speed of your modem.
Data bits is the number of bits in one character. This number is
usually seven or eight.
Stop bits indicate the end of a character. This number is usually
one or two.
Parity is an error-checking method and will be set to even, odd
or none.
These parameters, except for the modem speed, are usually abbre-
viated and combined. Common examples are N81 (no parity, eight
data bits and one stop bit) and E72 (even parity, seven data bits and
2 stop bits).
You set each of these in your communications program. Each
parameter must be set the same on both computers or you won't
be able to connect.
File Transfer Protocols
File transfer protocols are standards that govern how computers
transfer files between modems over a telephone line. Protocols
determine what type of error checking and data compression, if
any, occur during transfer. Based on a number of factors, some
protocols are faster than others. Popular protocols include XMO-
DEM (one of the earliest and still one of the most reliable proto-
cols) and ZMODEM (about the fastest available these days).
You don't really need to know anything about specific protocols—
just make sure you're using the same protocol as the computer
with which you're communicating. If you would like to know
more, protocols are described in any book on telecommunications,
available at your local book or computer store.
Part I: Getting To Know Your Computer