Teledesign Systems Inc TS4000GL Manuel D’Utilisation
TS4000 Radio Modem User’s Manual
AirNet Packet Protocol
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(mountaintop) locations. In some situations, the use of a repeater may be
logistically difficult and may not completely solve all propagation problems. The
AirNet protocol provides an option where nodes can be set up as store and
forward repeaters. The relay nodes store packets that they receive and repeat
(forward) the packets when the channel is idle. The relay nodes can be set to
relay all packets or only packets with certain source or destination addresses.
Complete Packet Capability
logistically difficult and may not completely solve all propagation problems. The
AirNet protocol provides an option where nodes can be set up as store and
forward repeaters. The relay nodes store packets that they receive and repeat
(forward) the packets when the channel is idle. The relay nodes can be set to
relay all packets or only packets with certain source or destination addresses.
Complete Packet Capability
Nodes automatically re-send packets which are not received correctly.
Robust 32 bit CRC ensures that packets are received correctly.
Adjustable maximum number of retries.
Adjustable maximum packet size - Large packets can be automatically
broken up into smaller packets for reliable transmission.
broken up into smaller packets for reliable transmission.
Easy to Use Host Control and Status
The host (user equipment) controls operation of the packet protocol with
simple ASCII command strings.
simple ASCII command strings.
No special formatting of user data is required.
Status strings can be enabled to provide information on the success or
failure of packet transmissions.
failure of packet transmissions.
Addressing
Individual addresses from 1 to 999.
Group addresses from 1 to 60.
Various transfer types
Individual (point to point with acknowledge) - The acknowledgment
provides for guaranteed delivery of the data packets.
provides for guaranteed delivery of the data packets.
Individual without acknowledgment.
Group broadcast - Unacknowledged transfer to all members of a group.
Network broadcast - Unacknowledged transfer to all modems.
Multicast receptions - Allows a modem to receive group broadcasts to
groups other than its own. This can be used to create sub-groups or super-
groups of modems.
groups other than its own. This can be used to create sub-groups or super-
groups of modems.
Channel Access
CSMA/CA - Carrier Sense Multiple Access with Collision Avoidance.
Adjustable Transmission Index (transmit probability) - Allows a network to be
optimized for maximum efficiency.
optimized for maximum efficiency.
Adjustable Slot Time - Allows the modem to be optimized for different radios
and repeater systems.
and repeater systems.
Store and Forward Data Repeater
Any unit can be configured as a relay node. Allows for easy expansion of the
network.
network.
Repeater filter allows for repeating of only packets to or from select nodes.
This minimizes the amount of repeater traffic created.
This minimizes the amount of repeater traffic created.
Features