Eicon Networks 1550 - Manual (Page 110)

Web Interface Settings Glossary 110
HDLC Menu (VHSI Tree) > Timers Group (X.25)
The HDLC menu is only accessible through the Protocol page, when the protocol is set
to X.25.
Checkpoint T1
Defines the Check Point Timer, which specifies how long to wait for a response from
the remote device before an attempt is made to determine its status. This parameter
should be set to slightly greater than twice the transmission time of the longest frame.
Range: 200-9999 milliseconds. Default: 2900 milliseconds.
Ack Delay T2
Defines the Ack Delay Timer.
To optimize communications efficiency, acknowledgments can be piggy-backed onto
outgoing frames rather than being sent out on their own. The Ack Delay Timer defines
the length of time the device should wait for an outgoing information frame, before
sending the acknowledgement by itself. This setting (T2) should always be much less
than the Check Point Timer (T1) otherwise, the remote device may time out and try to
recover before the acknowledgment is received.
Range: 0-9999 milliseconds. Default: 200 milliseconds.
Idle Probe T3
Defines the Idle Probe Timer, which specifies how long the link should remain idle
before the Eicon 1550/1551 sends an RR (Receiver Ready) frame, with a P bit set, to
the remote device. This is done in order to determine its status. The remote device, if
still functioning, will respond using an RR frame with the F bit set.
Range: 0-99999 milliseconds. Default: 15000 milliseconds.