User manual
4.5.1 Signaling type
There are two types of signaling available to the FXS ports: Loop Start or Ground Start.
Loop Start is a two-way, two-wire (tip and ring) signaling method in which the current used for the signaling
ows in a circuit (loop) between a telephone and PBX or a telephone and a central ofce. Seizure of the line is
accomplished by going off-hook which causes current to ow in a circuit (loop).
Ground Start is a method of signaling from a terminal or subscriber loop to a switch, in which method one side
of a cable pair is temporarily grounded.
When used as a trunk, loop start lines are more susceptible to event of glare when both sides try to seize the
line simultaneously. Ground start is less affected by this problem and is preferred way to establish a trunk with
FXS interface. Support for ground start signaling will be added in the next versions of rmware.
Note: Ground Start Signaling is not available on all simulator models. Please consult manufacturer before
purchasing if this feature is important to you.
4.5.2 Line impedance
600 Ohm or 800 Ohm selectable impedance is available for each FXS port
4.5.3 Assigning Phone numbers
There are two phone numbers that can be assigned to each FXS port.
Each number can be from 1 to 16 digits long. You can dial either one to call a particular FXS port.
You can use secondary phone numbers to create a Hunt Groups or to test custom ring cadences.
Default numbers for each port are two digit numbers:
FXS 1 First number 11, Second number 12
FXS 2 First number 21, Second number 22
FXS 3 First number 31, Second number 32
FXS 4 First number 41, Second number 42
FXS 5 First number 51, Second number 52
FXS 6 First number 61, Second number 62
FXS 7 First number 71, Second number 72
FXS 8 First number 81, Second number 82
4.5.4 Conguring ring cadence
Cadence is the rhythm of the ring voltage applied to a telephone connected to FXS port.
It is dened as a sequence of ON and OFF timers.
You can congure two ring cadences for each FXS port. One cadence for each phone number.
Default value for Phone 1 is: 1000ms ON, 3000ms OFF
Default value for Phone 2 is: 500ms ON, 400ms OFF, 500ms ON, 400ms OFF, 2000ms OFF
PSTN Manager allows following values for the Cadence timers:
From 0ms to 9999ms with 1ms increment
Note: Using a 0 value for the rst ON timer will prevent a ring on that FXS port. This can be useful for
maintaining quiet environment, when the ring noise is not desirable, however work still has to be done.
22
User Manual
Public Switched Telephone Network (PSTN) Simulators