5、cs: simplified header and extension; big enough address space and hierarchy address architecture; Plug and Play internet working; authentication and encryption on network layer; support on service quality; better support on mobile communication. IPv6will replaceIPv4.Theentirenetworkf
6、romIPv4transitiontoIPv6needforalongtime,thetwonetworkswillcoexistforalongtimeinthefuture.SoexploretheIPv4andIPv6connectivityandtransitiontechnologyhasimportantsignificance.Thispaper introduces thedisadvantagesofIPv4, and themanyadvantagesofIPv6.Analyzeseveralcommoncommunicationtechno