Packet Sender is an open source utility to allow sending and receiving TCP and UDP packets. It also supports TCP connections using SSL, intense traffic generation, HTTP(S) GET/POST requests, and panel generation. It is available for Windows, Mac, and Linux. It is licensed GNU General Public License v2 and is free software. Packet Sender's web site says "It's designed to be very easy to use while still providing enough features for power users to do what they need.".
Uses
Typical applications of Packet Sender include:
Troubleshooting network devices that use network servers (send a packet and then analyze the response)
Troubleshooting network devices that use network clients (devices that "phone home" via UDP, TCP, or SSL—Packet Sender can capture these requests)
Testing and development of new network protocols (send a packet, see if device behaves appropriately)
Troubleshooting secure connections (using the SSL server and client).
Automation (via Packet Sender's command line interface or resend feature)
Stress-testing a device (using intense network generator tool)
Sharing/Saving/Collaboration using the Packet Sender Cloud service
Packet Sender comes with a built-in TCP, UDP, SSL, DTLS server on multiple ports a user specifies. This remains running listening for packets while sending other packets.
Features
As of version v8.1.1 Packet Sender supports the following features:
Live traffic log (Time / From IP / From Port / To IP / Method / Error / ASCII / HEX)
Persistent TCP and SSL Connections
HTTP Requests with Auth headers
Portable Mode
IPv6 Client / Server
IPv4 Subnet Calculator
Saved packets (with sending directly from saved list)
Mixed ASCII packet notation (ASCII with embedded syntax to allow hex)
Multiple TCP servers
Multiple UDP servers
Multiple SSL servers
Multiple DTLS servers
Multicast send and receive
Packet resending at n intervals (where n is seconds)
Multi-threaded TCP/SSL/DTLS connections
Command-line interface
Packet responses
Smart Packet responses
Macros inside packet responses for TIME, DATE, UNIXTIME, RANDOM, UNIQUE
Packet search (for saved packets)
Packet export/import
Intense Traffic Generator (UDP Flooding) via GUI or CLI
Quick-send from traffic log
Save traffic log
Panel Generation for scripting buttons
Packet Sender Cloud
Platforms
Windows (64-bit)
OS X (Intel-based x86-64 or ARM-based Macs)
Linux (Source Distribution with Qt or x86-64 AppImage or Snap)
Packet Sender Mobile is available on iOS. It only has the core features of desktop Packet Sender (send, receive, TCP, UDP, and Cloud).
