Integrated packet generator and sniffer for Ethernet, but also works with blocks of data over TCP connection. Enables you to use scripts for automated testing, monitoring, imitating of various network objects, creating custom network tools.
jNetStream is a sniffer and a protocol analyzer. Includes applications and library. 100s of protocols are defined. Includes scripting. It is appropriate for custom protocol development, grad students, and network teachers/professors. Full SDK included.