Most of the network protocols currently in use have changed little since the early definitions of the ARPA research and education network when trust was the norm. To have a secure foundation for the critical Internet applications of the future, severe weaknesses must be addressed: lack of encryption to preserve privacy, lack of cryptographic authentication to identify the source of information, and lack of cryptographic checksums to preserve the integrity of data (and the integrity of the packet routing information itself). New internetworking protocols are under development which use cryptography to authenticate the originator of a packet and to protect the integrity and confidentiality of data. The IETF (Internet Engineering Task Force) Proposed Standard for the Next Generation Internet Protocol (IPng) is being designed to cope with the vastly increased addressing and routing needs associated with the exponential growth of the Internet. IPng provides integral support for authenticating hosts and protecting the integrity and confidentiality of data. The first release of IPng is officially termed IPv6 (Internet Protocol version 6). Since it is impractical to replace the existing protocol instantly and simultaneously throughout the Internet, IPv6 is designed to coexist with the current version of IP, allowing for a gradual transition over the course of years. Implementations of IPv6 for many routers and host operating systems are underway. In the future, authentication protocols will increasingly be supported by technology that authenticates individuals (in the context of their organizational or personal roles) through the use of smart cards, fingerprint readers, voice recognition, retina scans, and so forth. Protocol design, analysis, and implementation will be the subject of continued research. A primary goal is 100% verifiably secure protocols (that is, protocols as provably secure as the cryptographic algorithms supporting them), but researchers are nowhere near attaining this goal.