Electronic Communication Network

What is different between FIX Protocol and (ECN) Electronic Communication Network FOR trading?
or ARE FIX protocol is Technology use in (ECN)?

FIX: https://en.wikipedia.org/wiki/Financial_Information_eXchange
ECN: https://www.investopedia.com/terms/e/ecn.asp

FIX is an electronic communications protocol whereas ECN is an an electronic communications network. ECNs could use any protocol to send messages back and forth. FIX happens to be the most popular and widespread protocol for trading, probably also because it is an open and free standard.