Critical Decisions, Myths & Lessons Learned in Networking What is important at the time may be only apparent with hindsight What seems important at the time may not turn out to be

A sampler from the ‘70s & ’80s Myth – The ARPANET will be the world’s computer communication network. Reality – It put packet switching on the map and supported the computer science research community for two decades. Myth – The NSFNET would provide the Internet backbone for the research and education community Reality – Commercial networks took over and the NSFNET lasted less than a decade. It did knit together computer science researchers and the higher education community

A sampler from the ’90s & ’00s Myth – The World Wide Web will be the information access system for the world Reality – Not clear, but with the advance of technology, almost surely other better systems will emerge in the future. Myth – A layered telecommunications architecture is the best solution for the future Reality – Not clear, but the likelihood is that at least some of the interested parties, both service providers and applications developers, will envision applications that are integrated with the underlying infrastructure.

Some Critical Decisions Open Architecture – defined interfaces, protocols and objects The creation of IP for global addressing Addresses going from 16 bits to 32 bits X Leave Security & Authentication to later X The implementation of TCP as a VC X Creation of supporting infrastructural mechanisms – ICCB, IAB, IETF

Some Lessons Learned Architectural change to existing structures is harder than creation of new structures Transitioning from key protocols is difficult Be careful about what you select; anything widely used is hard to supplant – e.g. DNS Good ideas need to be easily understood or it will be difficult to get them adopted Packaging may make or break a user application

Some Observations Late Binding is usually a better choice than early binding Indirection is a powerful tool to accommodate change Persistent identifiers should be free of syntax and semantics as much as possible Context changes should be handled without substantive user involvement

About Intellectual Property Copyright and Patent rights are set forth in the Constitution Enforcement of usage is not the same as notification of rights or terms & conditions Patents can be used for both defensive as well as offensive purposes Copyright rights are not the same as patent rights Most devices could care less, not so for us