|The Verify Parameters affect various timeouts that the NetTest hardware uses to perform dialing for Automatic Number Identification. Listed are the values that appear on the Verify Options screen and what they mean. |
Dialtone Timeout - This is the length of time the NetTest will wait for dialtone after it goes off hook. Increasing this value will allow the NetTest to detect dialtone where there is a switch that takes along time to respond. However, this will also increase the length of time it takes to determine that there is no dialtone on the line and will reduce performance. (default = 2200ms, min = 500ms, max =3000)
Dialtone Valid - This is the length of time that the dialtone must be valid within the Dialtone Timeout period and represents a window of time within the Dialtone Timeout period that must contain valid dialtone. (default = 100ms, min = 50, max = 1000)
(With the default parameters, the NetTest must detect a dial tone for a solid 100 ms within the first 2200ms after going off hook otherwise it will return NDT or NSDT).
Call Progress Timeout - This is the length of time, after dialing, that the NetTest will wait for the first DTMF digit to be returned by the ANAC device. If not digit is returned then, presumably, a NANI is returned, Increasing this value will allow the NetTest unit to capture the Phone Number returned by the ANAC device in areas where the device takes a long time to respond. However, this will also increase the time it takes for the NetTest to detect NANI (No ANI) and reduce test performance. (default = 15000ms, nub = 4000, max = 3000)
Call Progress Accumulation - While the NetTest is waiting for the first DTMF digit other tones may be detected on the line. These tones may be pulses or other erratic noise, such as voice data, so the length of time these tones are detected is accumulated in 25ms increments. If this accumulated total exceeds this limit then CPT (Call Progress Tone) is returned by the NetTest. If CPT is returned the DaVaR software will then perform Cadence Analysis to determine what type of tones were detected. (default = 4500ms, min = 100, max = 1000)
Determining the End of the Verify Number
The DTMF sequence returned from the ANAC has a specific inter digit timeout period and when this period is exceeded the NetTest determines the string of digits has ended. This value is not settable in firmware.