Wireshark - Wireshark is a network protocol analyzer for Unix and Windows. It lets you capture and interactively browse the traffic running on a computer network.
Debookee - Debookee is the simplest & most powerful network traffic analyzer for macOS.
tcpdump - tcpdump is a common packet analyzer that runs under the command line.
NetworkMiner - NetworkMiner is a Network Forensic Analysis Tool (NFAT) for Windows.
Ettercap - Ettercap is a suite for man in the middle attacks on LAN.
SmartSniff - SmartSniff is a packet sniffer that capture TCP/IP packets and display them as sequence of conversations between clients and servers.