appneta/tcpreplay
FreePcap editing and replay tools for *NIX and Windows - Users please download source from
FreeFree tier
About appneta/tcpreplay
Tcpreplay is a suite of GPLv3 licensed utilities for UNIX (and Win32 under Cygwin) operating systems for editing and replaying network traffic previously captured by tools like tcpdump and Wireshark. It allows users to classify traffic as client or server, rewrite Layer 2, 3 and 4 packets, and replay traffic through network devices such as switches, routers, firewalls, NIDS and IPS. It supports both single and dual NIC modes for testing sniffing and in-line devices, and includes enhancements for high-speed performance via netmap, flow statistics, and flow analysis. The suite includes tools: tcpreplay, tcpreplay-edit, tcpliveplay, and tcpprep.
Key Features
Edit and replay pcap files at arbitrary speeds
Classify traffic as client or server
Rewrite Layer 2, 3 and 4 packets
Support single and dual NIC modes
Include netmap support for 10GigE wire-speed performance
Provide flow statistics including Flows Per Second (fps)
Enable flow analysis for tuning expiry timeouts
Comprise tools: tcpreplay, tcpreplay-edit, tcpliveplay, tcpprep
Pros & Cons
Pros
- Open source under GPLv3, free to use and modify
- Widely used by networking vendors, enterprises, and universities
- Supports high-speed replay with netmap for wire-speed performance
- Includes multiple tools for different replay and editing needs
- Can rewrite packets at multiple OSI layers
Cons
- Limited to Layer 2 replay on network hardware (does not penetrate deeper without tcpliveplay)
- Windows support requires Cygwin, which adds complexity
- Setup and configuration can be complex for beginners
- Primarily focused on network testing, not general-purpose AI tool
Best For
Testing network devices such as switches, routers, firewalls, NIDS, and IPSTesting and tuning IP Flow / NetFlow hardwareReplaying TCP traffic to live servers for application testingSecurity assessment and penetration testing through traffic replayPerformance testing of network infrastructure
FAQ
What platforms does tcpreplay support?
Tcpreplay supports UNIX operating systems and Windows under Cygwin.
What types of network traffic can be replayed?
Tcpreplay can replay pcap files captured by tools like tcpdump and Wireshark, supporting TCP, UDP, and other protocols.
Is tcpreplay open source?
Yes, tcpreplay is licensed under GPLv3 and is freely available.
What tools are included in the tcpreplay suite?
The suite includes tcpreplay, tcpreplay-edit, tcpliveplay, and tcpprep.