Macroscopically Sustainable Networking: On Internet Quines Barath Raghavan and Shaddi Hasan ICSI and UC Berkeley ABSTRACT previous eighty, and have provided an environment in which the The Internet stands atop an unseen industrial system required for its Internet has been able to grow at a phenomenal pace. Political continued growth, operation, and maintenance. Its scale could not instability—resulting in the shutdown of the Internet for whole have been achieved without this reliance, and its dependencies— nations—in the last several years has dramatically demonstrated ranging from sophisticated manufacturing facilities to limited raw the fragility of the Internet on a regional scale. The effects of materials—make it vulnerable to supply-chain disruptions, which widespread climate change and energy limits are predicted to have are more likely as human society faces global ecological limits. significant impacts on the global economy, in turn threatening to the We introduce the concept of an Internet quine, a metaphor that disrupt global supply chains upon which the Internet depends [19]. represents a collection of devices, protocols, manufacturing fa- Achieving structural resilience against such challenges, be they cilities, software tools, and other related components that is self- at a global, regional, or national scale, calls for a set of networking bootstrapping and capable of being used (by engineers or au- technologies and components that do not carry such heavy exter- tonomously) to reproduce itself and all the needed components of nal dependencies and that are truly sustainable [14]. For lack of the Internet. In this paper, we study the nature of Internet quines a better term, we call such a set of technologies required to create a self-sustainable Internet an Internet quine, and in this paper ex- and discuss how they could be built. We also attempt to identify a 1 collection of such tools and facilities, and how small and inexpen- plore how to build an Internet quine. In particular, we consider sive they can be made. quines with minimal dependencies, adopting as much as possible the principles of “appropriate technology” [9, 21], namely an In- ternet quine that is a) simple, b) locally reproducible, c) composed CCS Concepts of local materials and resources, d) easily repairable, e) affordable, •Networks ! Network components; •Hardware ! Communica- and f) easily recyclable. tion hardware, interfaces and storage; Such a quine would have a variety of useful applications. In resource-constrained environments (such as parts of the so-called Keywords developing world, or in areas isolated by natural disasters), a func- tional Internet quine could ensure a link to the rest of the world. Sustainability; life-cycle analysis It could also serve as the basis for a non-government controlled communications infrastructure for people living under an authori- 1. INTRODUCTION tarian regime that practices widespread censorship. The process of The Internet is arguably the largest and most successful techno- building an Internet quine could also have great pedagogical value, logical system humanity has ever created. It is composed of a com- allowing students to “build the Internet from scratch.” Moreover, plex array of hardware and software assembled around the world many of the objectives we explore are part of the networking canon: with materials, energy, skills, and designs also from a global re- we aim to build networks that are scalable and can be started and source base. The fact that the Internet has spread to all regions of tested at a small scale with modest resources, modular networks the world despite this complexity is a testament to its tremendous separated into distinct elements that can be replaced at different utility and the ingenuity of those involved in the design, manufac- scales and technological levels, networks that remain useful under ture, distribution, and operation of its constituent components. changing conditions and respond to pressures, and open networks With this complexity comes vulnerability to threats: disruptions that do not require certain systems or components to function. in global supply chains, energy shortages, societal instability, and What an Internet quine would look like is highly dependent on government intervention into its operation. The last two decades the particular context in which it would be used. As such, we do have been relatively placid compared with the previous eight or not propose a single way forward, but weigh what knowledge and resources can be assumed to exist outside the quine and what ser- Permission to make digital or hard copies of all or part of this work for personal or vices it must support. Specifying an Internet quine in its entirety is classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation difficult, as the scale of the Internet and its constituent systems is on the first page. Copyrights for components of this work owned by others than the vast. In this paper we focus on a more tractable goal, that of explor- author(s) must be honored. Abstracting with credit is permitted. To copy otherwise, or ing the manufacturing and operational dependencies of supporting republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from [email protected]. a common use case of the Internet today: end to end communi- LIMITS ’16, June 08-10, 2016, Irvine, CA, USA 1 c 2016 Copyright held by the owner/author(s). Publication rights licensed to ACM. A quine is a computer program that outputs its own source code; ISBN 978-1-4503-4260-5/16/06. $15.00 metaphorically, an Internet quine is an Internet composed of sys- DOI: http://dx.doi.org/10.1145/2926676.2926685 tems that can reproduce that whole Internet. cation over long distances. We then consider possible alternative difficult to say which of these uses is most intrinsic or essential. For architectures for supporting this use case. Our hope is to provide a concreteness, here we consider the use case of end-to-end commu- small nudge towards sustainability. nication between two Internet users who are geographically distant. We assume that the components they use are standard—the routers, 2. RELATED WORK data centers, transmission systems, operating systems, and so forth that are in use today. Curiously, though the example we begin with The goal of an self-sufficient Internet of the sort we study here is simple, upon study of its dependencies we uncover a great deal is not a new one. In a broader sense, its roots date to the work of complexity and interdependence. At the outset, we note that in of the economist E.F. Schumacher, who introduced the concept of piecemeal this analysis has been done by many in the research lit- intermediate technology, now known as appropriate technology— erature and industry, but to our knowledge a semi-comprehensive technology that is appropriate for a region rather than being cre- picture of the Internet’s dependencies has never been painted. ated as a global commodity [21]. Schumacher’s idea of appropriate technology is one that we might well heed today as we face ecolog- 3.2 Dependencies ical limits. Similarly, the structure, and downsides, of a complex We depict the dependencies of the various components of the system (such as the Internet) that embodies a mix of technological Internet beginning from our use case in Figure 1. Each box de- and human elements was studied by historian of technology Lewis notes an abstract or concrete component, resource, or function of Mumford throughout the 20th century [11, 12]. the Internet or one of its recursive dependencies. Arrows denote More recently, a range of scientists and engineers, from ecol- dependency; dashed arrows denote optional dependency—that is, ogists to computer scientists, have explored building sets of self- a “one of these” relationship. Moving down the chart, we quickly sufficient machines. The Open Source Ecology project aims to traverse the abstract layers—which represent functional elements provide a complete set of designs for appropriate technology that that we recognize as central to the Internet (such as routers)—and meets all basic human needs [13]; among their tools are several on to the lower layers which reside in the realm of hardware. As the means of manufacturing, including a 3D printer, RepRap [20]. Internet currently uses the latest IC manufacturing and fiber optics, There are numerous 3D printer projects that are capable of self- we consider the consequent dependencies of those technologies and manufacture but all still require significant material inputs. The related processes. Once we move beyond hardware manufacturing Fablab project has similar abilities and ambitions and has aided in we enter the realm of chemical compounds and natural resources setting up networks in Afghanistan [5]. that are required for many of the relevant manufacturing processes, Many of these efforts stem from the ICTD community, which has from making optical fiber to printing circuit boards. We terminate also studied many of the issues we consider here. Since resource- with special nodes that represent ores or otherwise naturally occur- limited environments break design assumptions that the Internet’s ring resources. infrastructure relies upon, they complicate the deployment and We do not depict operational or deployment dependencies since evaluation of networked systems [4]. Understanding the challenges they tend to involve a small number of processes—notably, power that a network’s economic, technical, and social contexts presents is generation and transportation—which ultimately have to do with essential for achieving its long-term sustainable operation [3,8,23]. energy technologies and resources. These dependencies are very Such an understanding of the present Internet infrastructure is sur- important as energy will be a significant global challenge this cen- prisingly difficult to come by, further motivating our current study.