Echelon LonTal Stack - Manual (Page 180)

168 Appendix C: Appendix C
Neuron C Syntax for the
Model File
network variables.
This keyword is not required for model files. Names of array elements are
automatically expanded by the LonTalk Interface Developer compiler.
offline
Specifies that a network management tool must take this device offline, or
ensure that the device is already offline, before updating the network
variable.
Do not use this feature in the bind_info for a configuration network variable
that is declared using the config_prop or cp keyword. Instead, use the
offline option in the cp_info.
unackd | unackd_rpt | ackd [ ( config | nonconfig ) ]
Selects the LonTalk protocol service to use for updating this network
variable. The allowed types are:
unackd — unacknowledged service; the update is sent once and no
acknowledgment is expected.
unackd_rpt — repeated service; the update is sent multiple times and no
acknowledgments are expected.
ackd (the default) — acknowledged service with retry; if acknowledgments
are not received from all receiving devices before the layer 4 retransmission
timer expires, the message is sent again, up to the retry count.
An unacknowledged (unackd) network variable uses minimal network
resources to propagate its values to other devices. As a result, propagation
failures are more likely to occur, and failures are not detected by the device.
This class might be used for variables that are updated on a frequent,
periodic basis, where loss of an update is not critical, or in cases where the
probability of a collision or transmission error is extremely low.
The repeated (unackd_rpt) service is typically used when a message is
propagated to many devices, and a reliable delivery is required. This service
reduces the network traffic caused by a large number of devices sending
acknowledgements simultaneously and can provide the same reliability as
the acknowledged service by using a repeat count equal to the retry count.
The config keyword indicates that this service type can be changed by a
network management tool. This option allows the tool to change the service
specification during installation. config is the default.
The nonconfig keyword indicates that this service cannot be changed by a
network management tool.
authenticated | nonauthenticated [ ( config | nonconfig ) ]
Specifies whether the network variable update requires authentication. With
authentication, the identity of the sending device is verified by all receiving
devices. Abbreviations for authenticated and nonauthenticated are auth
and nonauth.
The config keyword indicates that this service type can be changed by a
network management tool. This option allows the tool to change the service
specification during installation. config is the default
The nonconfig keyword indicates that this service cannot be changed by a
network management tool.