Kantronics KAM 98, Руководство пользователя

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Sending a Message to Another Station
A quick way to see the basic components of packet radio in action is to follow a
simple message as it goes from one station to another, via an intermediate station.
Let’s assume that an originating station, WØXI, wants to send the message
“HELLO” to a destination station, KBØNYK. Also, assume that WØXI knows
that his signal might not reach KBØNYK’s station directly, but that it can be
picked up and repeated by an intermediate station, NØGZZ, and then received by
KBØNYK.
The following are the basic steps of a station-to-station packet communication, as
seen from the point of view of the message, “HELLO,” sent from source station
WØXI to destination station KBØNYK, through intermediate station NØGZZ.
Step 1 is a one-time configuration task, Steps 2-3 establish a connection between
stations, and Steps 4-13 follow the “HELLO” message from the time it is created
by WØXI to when it is read by KBØNYK.
Step 1. Before this message can be transmitted from a source
station to a destination station, via an intermediate sta-
tion, all the stations involved have to have callsigns ,
which are used by the TNCs involved to identify and
process information (e.g., source, destination, and rout-
ing of information).
So we start by assuming each operator involved in this
example has already performed this one-time configura-
tion task, creating the callsigns given above. Stations are
identified by reference to their callsigns . Note that a
callsign can be for a TNC or for a Personal Bulletin
Board System (PBBS) “mailbox” that resides in RAM
inside the TNC.
Step 2. This communication begins when the operator of station
WØXI turns on his computer, his TNC, and the trans-
ceiver of his station and uses a computer software pro-
gram to tell the TNC that he wants to establish a line of
communication, called a “connection,” with a “destina-
Introduction Packet Communication
User’s Guide 24 KAM’98 v 8.3