Ethreral Network Protocol Analyzer is now Wireshark. Written by networking experts, wireshark has won trust among the networking professionals who use it for analysis, trouble shooting, software and protocol development and education. wireshark requires WinPcap 4.x and along with the regular features of a protocol analyzer it consists of certain exclusive features in the group of softwares. In this version, many bugs from the previous editions have been successfully fixed. Some of them are: various memory leaks, OS X Intel package incorrectly claimed to be Universal, complication during compiling without zlib  and many more. Since it is an open source license allowing experts in networking to improve it continually, this is a protocol analyzer becomes more and more resourcefull