User manual

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Finally, you can also export PhoneSweep-generated data such as phone numbers and call results using
the Export button. See Section 6.3, Exporting Data, for more information.
2.9 Single Call Detect (SCD)
Single Call Detect (SCD) is a unique PhoneSweep feature that speeds telephone scanning and improves
the accuracy and detail of information collected in the scan. In SCD mode, PhoneSweep listens to and
evaluates each telephone call as it is made, and modifies its calling behavior accordingly.
Single Call Detect:
• Reduces the total number of calls that are needed to complete a scan
• Allows faster voice recognition (Voice lines are called just once).
• Decreases the probability of some testing injuries
• Identifies many toll fraud vulnerabilities by detecting second dial tones
SCD overcomes many of the limitations of conventional telephone scanning and increases the capabilities
of many off-the-shelf modems. It allows faster voice detection and reduces the possibility that redundant
calls will be made in the course of a scan. All versions of PhoneSweep include SCD.
Conventional telephone scanning is limited by inflexibilities inherent in modem design. Standard
fax/modems can place calls in either “data” mode or in “fax” mode, but cannot place calls in both modes
simultaneously. Thus, a conventional scan requires two calls to each number to locate modems and fax
machines; all the numbers must be called in data mode to locate modems, and then called again in fax
mode to locate fax machines. SCD eliminates the second call to any numbers that are not connected to a
device possibly capable of fax communication, thereby reducing the total number of calls in the scan and
reducing the time required to complete the scan.
Conventional telephone scanning is also limited by the fact that few modems can reliably identify a
human voice answering the phone, and fewer still can detect a second dial tone. Telephone scans that
cannot recognize Voice run a high risk of leaving blank voicemail messages and confusing or irritating
employees. “Second dial tone” happens when dialing a telephone number results in another dial tone.
Detection of second dial tones is essential for detecting unauthorized “telephone extenders” that can be
abused to commit toll fraud. SCD detects both by bypassing normal modem synchronization.
2.9.1 How SCD improves scan speed and accuracy
When PhoneSweep in SCD mode is used to perform a telephone scan, the modem and computer listen to
and evaluate each call as it is being made, and modifies calling behavior accordingly. If PhoneSweep
detects:
• A live or recorded human voice, it immediately hangs up and marks the number as “VOICE.”
• A second dial tone, it hangs up and marks the number as “TONE.”
• A Busy signal, it hangs up and marks the number as “BUSY.”
• Ringing when the call timeout occurs, it hangs up and marks the number as “TIMEOUT.”
Except for those flagged "BUSY", these numbers will not be called again.
Two calls are made to lines to that generate fax and/or modem tones: If PhoneSweep hears tones from a
modem, it automatically switches the calling modem into fax mode to determine whether a fax-capable
device produced the tones. PhoneSweep then schedules a second call to the same number in data mode to
determine if the answering device is also capable of data communications.