Article · Wikipedia archive · Last revised Jun 28, 2026

Bit-Twist

Bit-Twist is a powerful libpcap-based Ethernet packet generator and packet capture editor, written in POSIX-compliant C, designed to complement tcpdump by replaying captured traffic from pcap files onto live networks. It supports Windows, Linux, BSD, and macOS, allowing the editing of key fields in Ethernet, ARP, IPv4, IPv6, ICMP, and TCP/UDP headers. It can also generate pcap files from its built-in templates, enabling packet creation without existing capture files, along with payload generation from uniformly distributed random bytes or fixed bytes, such as hex streams from Wireshark. Ideal for testing firewalls, IDS, IPS, routers, switches, load balancers, and other network equipment, it delivers performance that matches the line rate of NIC, up to 10Gbps.

Last revised
Jun 28, 2026
Read time
≈ 1 min
Length
141 w
Citations
—
Source
Wikipedia ↗
Bit-Twist
Original authorAddy Yeow
Stable release
4.7 / November 1, 2024
Operating systemWindows, Linux, FreeBSD, NetBSD, OpenBSD, macOS
TypePacket generator
LicenseGNU General Public License
Websitebittwist.sourceforge.io

Bit-Twist is a powerful libpcap-based Ethernet packet generator and packet capture editor, written in POSIX-compliant C, designed to complement tcpdump by replaying captured traffic from pcap files onto live networks. It supports Windows (using Npcap), Linux, BSD, and macOS, allowing the editing of key fields in Ethernet, ARP, IPv4, IPv6, ICMP, and TCP/UDP headers. It can also generate pcap files from its built-in templates, enabling packet creation without existing capture files, along with payload generation from uniformly distributed random bytes or fixed bytes, such as hex streams from Wireshark. Ideal for testing firewalls, IDS, IPS, routers, switches, load balancers, and other network equipment, it delivers performance that matches the line rate of NIC, up to 10Gbps.

External links