Paper review: The Design Philosophy of the DARPA Internet Protocols

Reviewer: Michael S. Liu

I would like to address the question listed on the class webpage:

"One goal of the Internet is to support a variety of services at the transport level. Is this a good goal? Which one is better: a separate network for services such as telephone, cable, and TV, or a combined network for all of them? What are the advantages and disadvantages of having a single network?

I think the paper does a good job of outlining the benefits of the internet as well as its drawbacks. The fundamental goal of the internet the paper states is: " develop an effective technique for multiplexed utilization of existing interconnected networks", in other words to connect different networks together. The alternative to this, the paper states, is "to create a unified system which incorporated a variety of different transmission media, a multimedia network". These two contrasting goals, a single network supporting different uses and a multiple media network each with a single specialized purpose, are at the core of the question being asked above. The paper discusses how the internet has chosen to be a single network that supports multiple uses and how it has made that work. The implementation that resulted in the Internet chose for itself a list of goals that were ranked in this order of importance:

Those goals defined the Internet based on the needs that needed to be fulfilled at its constructions. At the time, a network for effective multimedia traffic was not one of the needs it need to meet. The Internet today is being asked to carry large amounts of multimedia traffic and this is not what it was designed primarily for at its outset. It was designed to be flexible but that flexibilty is being exhausted by the needs demanded of the Internet today. Thus, we must rethink the design of the Internet as we think about the needs it must meet today.

As we design for the Internet of tommorow, based on the needs of today and hopefully of tommorow, we must once again question the solution that was given to the problem that was posed in the past when the Internet was first created. I propose that perhaps it may not be wise to continue work on the Internet merely concerned about the interconnection of different networks for any and all purposes. Perhaps, there may be some wisdom to create a hybrid system that unites the best aspects of the Internet currently with the best aspects of specialized separate networks. Obviously, there was a need that specialized networks did not meet and that is why the Internet was created. However, the Internet today is not designed to handle high bandwidth multimedia traffic that may crowd all the other conventional Internet traffic that its networks are currently handling. Perhaps interconnection between different networks of the same type may be a better solution. That way the general connectivity is preserved but the data loads are specialized so they do not infringe on each other. We already tried to create the supermarket of networks which is the Internet where any and all goods can be obtained. But, perhaps, we still need our fish market and bakeries where speciality goods are obtained. Just as these specialty shops exist today in commerce. Perhaps, specialty versions of the Internet can be created to bring the best of both worlds of general and specialized networks together.