PCAP Gap Detector

Detects timestamp gaps in PCAP files.

Requirements

• Python 3.6+
• Scapy

pip install scapy

Usage

python pcap_gap_detector.py --pcap <file> --seconds <threshold>

Options

--pcap <file>           PCAP file to analyze (required)
--seconds <threshold>   Gap threshold in seconds (required)
--csv <output.csv>      Export gaps to CSV file
--no-color              Disable colored output

Examples

Basic usage:

python pcap_gap_detector.py --pcap capture.pcap --seconds 5

Export to CSV:

python pcap_gap_detector.py --pcap capture.pcap --seconds 5 --csv gaps.csv

How It Works

1. Reads PCAP file in batches
2. Detects gaps between packet timestamps that exceed the threshold
3. Reports gaps with packet numbers and timestamps

CSV Output

When using --csv, exports the following columns:

• gap_number
• packet_start
• packet_end
• timestamp_start_utc
• timestamp_end_utc
• gap_seconds
• gap_duration

License

BSD 3-Clause License

Copyright (c) 2025, Justin Hendren

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.