Scalability Perspectives is a series of posts that highlights the ideas that will shape the next decade of IT architecture. Each post is dedicated to a thought leader of the information age and his vision of the future. Be warned though – the journey into the minds and perspectives of these people requires an open mind.
Van Jacobson
Van Jacobson is a Research Fellow at
PARC. Prior to that he was Chief Scientist and co-founder of Packet Design. Prior to that he was Chief Scientist at Cisco. Prior to that he was head of the Network Research group at Lawrence Berkeley National Laboratory. He's been studying networking since 1969. He still hopes that someday something will start to make sense.
Scaling the Internet – Does the Net needs an upgrade?
As the Internet is being overrun with video traffic, many wonder if it can survive. With challenges being thrown down over the imbalances that have been created and their impact on the viability of monopolistic business models, the Internet is under constant scrutiny. Will it survive? Or will it succumb to the burden of the billion plus community that is constantly demanding more and more?
Does the Net Need an Upgrade? To answer this question a distinguished panel of Van Jacobson, Rick Hutley, Norman Lewis, David S. Isenberg has discussed the issue on the Supernova conference. In this compelling debate available on IT Conversations, the panel addresses the question and provides some differing perspectives. One of the perspectives is Content-based networking described by Van Jacobson.
A New Way to look at Networking
Today's research community congratulates itself for the success of the internet and passionately argues whether circuits or datagrams are the One True Way. Meanwhile the list of unsolved problems grows. Security, mobility, ubiquitous computing, wireless, autonomous sensors, content distribution, digital divide, third world infrastructure, etc., are all poorly served by what's available from either the research community or the marketplace. In this amazing
Google Tech Talk Van Jacobson use various strained analogies and contrived examples to argue that network research is moribund because the only thing it knows how to do is fill in the details of a conversation between two applications. Today as in the 60s problems go unsolved due to our tunnel vision and not because of their intrinsic difficulty. And now, like then, simply changing our point of view may make many hard things easy.
Content-centric networking
The founding principle of Content-centric networking is that a communication network should allow a user to focus on the data he or she needs, rather than having to reference a specific, physical location where that data is to be retrieved from. This stems from the fact that the vast majority of current Internet usage (a "high 90% level of traffic") consists of data being disseminated from a source to a number of users.
The current architecture of the Internet revolves around a conversation model, created in the 1970s to allow geographically distributed users to use a few big, immobile computers. The content-centric approach seeks to make the basic architecture of the network to current usage patterns.
The new approach comes with a wide range of benefits, one of which being building security (both authentication and ciphering) into the network, and at the data level.
Despite all its advantages, this idea doesn't seem to map very well to some of the current uses of the Web (like web applications, where data is generated on the fly according to user actions) or real-time applications like VoIP and instant messaging. But one can envision an Internet where content-centric protocols take care of the diffusion-based uses of the network, creating an overlay network, while genuine conversation-centric protocols stay on the current infrastructure.
Solutions or workarounds?
There are many solutions or workarounds for the problems posed by traditional conversation based networking such as Content Delivery Networks, caching, distributed filesystems, P2P and PKI. By taking the perspective of Van Jacobson we can investigate new dimensions of these problems. What could be the impact of this perspective on the future of the Internet architecture? What do you think?
I recommend the New Way to Look at Networking video by Van Jacobson. He tells us the brief history of Networking from the phone system to the Internet and his vision for dissemination networking.
Information Sources
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Wednesday, November 19, 2008 at 2:45AM 
will guide the readers through the best practices and introduce them to key areas of building distributed software systems using patterns.
The book pulls together 114 patterns and shows how to use them in the context of distributed software architectures. Although somewhat theoretical it is still a great resource for practicing distributed-systems architects. It is as close as you're going to get to a one-stop "encyclopedia" of patterns relevant to distributed computing. However it is not a true encyclopedia since "over 150" patterns are referenced but not described in POSA Volume 4. The book does not go into the details of the pattern's implementations, so the reader should already be familiar with the patterns, or be prepared to spend some time researching.
The pattern language for distributed computing includes patterns such as:
