Timing Parameters

Normally a FieldServer sends a poll request to a Server device and that device gives a response back to the FieldServer.

Following are the timing parameters considered important in the fieldserver’s operation:

 

Scan_interval: It is the amount of time between successive poll requests. Its default value is 2 seconds and it belongs to Map descriptors, nodes and connections.

 

Poll_delay: It is the time between receiving a response from a server device and the next poll request. Its default value is 0.05 seconds and it belongs to Connections only.

 

Timeout: If the FieldServer sends a poll request, and the Server device does not send a response, it is considered a timeout. The time for which the FieldServer waits before declaring a timeout can be adjusted by the timeout parameter. Its default value is 2 seconds and it belongs to Map descriptors, nodes and connections.

 

ic_timeout:  This parameter monitors the time between characters in a response. If the time exceeds the ic_timeout, the response is discarded and is considered a timeout. Its default value is 0.5 seconds and it belongs to Map descriptors, nodes and connections.

 

 

Retries: If a timeout occurs, then the FieldServer will retry the poll request a few more times. Number of times tried is specified by the retries parameter. Its default value is 3 times and belongs to nodes only.

 

Retry_interval: The interval between retries is specified by the retry_interval. The Fieldserver will send poll requests at the end of each retry_interval. Once the specified numbers of retries have been sent, theFieldServer will mark the node offline. Its default value is 10 seconds and belongs to nodes only.

Recovery_interval:Once a node has been marked offline, it will wait for a period specified by recovery_interval before sending another poll request. Its default value is 30 seconds and it belongs to nodes only.

Probation_delay: Once the communications have been re-established, the FieldServer will wait for a period called probation_delay, before marking the node as online. Its default value is 1 minute and it belongs to nodes only.