User's Manual

TS4000 Radio Modem User’s Manual AirNet Packet Protocol 23
Selection Description
Enable Packet
Operation
This activates packet operation for all user data.
The type of Medium Access Control (MAC) determines how a modem decides
when to transmit packets. This effects the transmission of both data and
acknowledgment packets.
Selection Description
Master-Slave The modem will transmit data as soon as the channel
becomes idle. This mode should only be used for master-
slave systems where two modems will never attempt to
transmit at the same time. This also implies that store and
forward relays are not used in the system.
CSMA Carrier Sense Multiple Access. This mode should be
selected for systems where multiple modems may attempt
to transmit simultaneously. With this setting, the modem
waits until the channel becomes idle and then transmits in
each following idle slot based on a random probability of
transmission (see CSMA MAC Options - Transmission
Index). This minimizes the potential for collisions in multi-
access systems.
Packet Activate
Medium (Channel) Access
Control (MAC)