User manual
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If you want to use PhoneSweep to scan ISDN devices, please refer to Section 3.9 “Recommended
ISDN capable modems“. We recommend that you if want to scan both ISDN and Analog modems, you
run separate scans over two different modems. ISDN modems are not Single Call Detect capable.
If you plan to use multiple modems, you must install a Multi-Port Serial I/0 card: Please see
More about Modem capabilities: Some modems can report more information about the results of a call
than other modems. The more capable modems can recognize:
• A second dial tone. These modems can determine when dialing a telephone number results in the
phone emitting a dial tone, as is the case with some telephone access codes. A modem that is
scanning with Single Call Detect will detect second dial tones and report them as “tone”.
• A phone answered by a human voice, such as a recorded voicemail message or an actual human
being.
• Remote ringing. A modem that supports remote ringing will report each time it hears a ring tone
while waiting for a remote device to answer. At this point, few modems support remote ringing,
and there are no modems that support both SCD and remote ringing.
PhoneSweep uses one of two methods for determining how long it should wait before ending a
connection, depending on the type of modem being used: “timeout in seconds” or “timeout in rings.”
• Modems that do not use Single Call Detect or report remote ringing will not be able to
determine when a line has picked up, nor will they be able to report if a call results in Voice and
Second Dial Tone responses. Non-SCD modems cannot tell the difference between a
“TIMEOUT” after a line has picked up and “RING TIMEOUT” when the line never picks up. In
these cases, PhoneSweep must rely on a “timeout in seconds” to end a connection. Calls that
SCD would answer as voice, a second dial tone, or do not pick up will all be reported as
timeouts.
• Modems that use Single Call Detect (but are not capable of remote ring detection) will
correctly report voice and second dial tone responses; however, for lines that do not pick up from
ringing, PhoneSweep must still rely on a timeout in seconds to end a connection that never picks
up. After call pickup, PhoneSweep uses “Single Call Detect Voice Timeout” to determine how
long to wait for a response (Voice, Tone, Fax or Modem) before reporting it as a timeout.
• Modems that support remote ring (but not Single Call Detect) will rely on the timeout in
rings to determine when to report a “RING-TIMEOUT.” As with other non-SCD capable
devices, voice and second dial tone responses will be reported as timeouts.
In general, Sandstorm recommends that you use external modems with PhoneSweep, rather than
internal modems. External modems are generally more configurable than internal modems, especially,
with regard to which IRQ their COM port uses. It is easier to diagnose problems with external modems,
and they are easier to replace if they fail.
Many internal modems are software-based win-modems*, such as ACP modems that come with IBM
ThinkPads. Even if they do work with PhoneSweep, you will not be able use Single Call Detect with
these modems, and you may have to turn off Single Call Detect in order to get any accurate results.
You do not have to install the modem drivers for a modem to work with PhoneSweep.