1. Challenges: Environmental Design for Pervasive Computing Systems An SAIC Company Ravi Jain*John R. Wullert II Autonomous Comm. LabApplied Research DoCoMo USA LabsTelcordia Technologies jain@docomolabs-usa.comjwullert@telcordia.com *Work performed while at Applied Research, Telcordia

2. Ravi Jain / 19-Sep-02 / 2 Outline  Motivation and background  Using less  Using it longer  Smart disposal  Conclusions

3. Ravi Jain / 19-Sep-02 / 3 Summary  Pervasive computing offers exciting opportunities but also possible negative environmental impacts  We need to treat environmental impact as a first- class design constraint  Increasingly software is a key to reducing environmental impact  We need research in many areas of system design for pervasive computing and communications

4. Ravi Jain / 19-Sep-02 / 4 Recycling Council of Ontario

5. Ravi Jain / 19-Sep-02 / 5 Frequently Raised Objections (FRO)  Just throw all the old PCs and cellphones into the sea –Ahem …  This is a naïve and ambitious plot to overthrow the capitalist system –No … we are just promoting environmentally sustainable design –Environmental responsibility has been embraced by many major corporations and governments  This is not really a big problem –We hope to show data that indicates otherwise  This is not my problem … why would I (or anyone) pay for this? –Legislation and consumer pressure is building –Market-leader advantages  This is not a computer science problem –We believe software, not hardware or materials, is increasingly important  This is not a research problem –We believe environmental factors can affect all layers of system design –Analogy with battery power considerations in mobile computing

6. Ravi Jain / 19-Sep-02 / 6 Computer waste (so far …)  Estimate: Over 75% of all computers ever bought in the US are stored in people’s attics, basements, garage … (MCC, 1996)  The growth of electrical/electronic waste is 3 times the growth of other municipal waste (AEA, 1997)  Estimate: By 2004 there will be over 315 million obsolete computers in the US alone (NSC, 1999) –4 billion pounds of plastics waste alone  Toxic materials in PCs (MCC, 1996) –Lead, Mercury, Cadmium, Arsenic, Chromium –Polyvinyl Chloride (PVC) –Polybrominated Diphenylethers (PBDE) –… –“New personal computers release over 100 different chemical compounds as gases, adversely affecting the health and performance of office workers”,  Technical Univ. of Denmark study, Environment Daily, 9 Sep 2002  Accounts for a significant proportion of U.S. energy consumption

7. Ravi Jain / 19-Sep-02 / 7 This is just the beginning Source: Rainer Malaka, EML ICDE 2001

8. Ravi Jain / 19-Sep-02 / 8 Pervasive Computing  Most pervasive computing devices consume less material than traditional PCs  However pervasive computing devices: –Will be far more numerous  Example: 13M Bluetooth devices shipped in 2001; Expect 780M by 2005 (Cahners In-stat) … compare with black phones –Rapid replacement due to low cost or immature technology –Can be disposable  Example: disposable cell phones (Telespree, HopOn) –Will be embedded in other products  Jewelry, clothing, smart floors, sensor networks, …  Makes location, extraction, collection, recycling harder –More likely to be lost, forgotten, or simply abandoned –Use batteries, likely exclusively –Will bring computer environmental impacts to regions where none exist at present

9. Ravi Jain / 19-Sep-02 / 9 A Challenge  Reduce total-lifecycle per capita computer & communications environmental impacts –Material and energy consumption by 10x –Non-recycled material and non-renewed energy consumption by 100x –Toxic and harmful byproducts by 1000x

10. Ravi Jain / 19-Sep-02 / 10 Design motivations  Not “The sky is falling …”, but pervasive computing does pose a new environmental risk  Design for the environment –Reduction of resource consumption –Reuse of resources and products –Recycling * Needs to be an integral part of the design process, not an afterthought * Recycling is important, but is not the answer * Software is increasingly important  We have an opportunity to do this while still at the start of the technology wave  Legislative and consumer pressure –Extended Producer Responsibility (EPR) in Europe  First-mover advantage (e.g. NEC Eco PC) –Many “socially responsible” advances are first resisted (e.g. Cellular 911) –Foresight sees market opportunities and differentiators

11. Ravi Jain / 19-Sep-02 / 11 Using less: Minimizing physical materials  Minimizing physical materials –Doing more with less, not Doing with less  Two parallel trends –Integration: cell phone as pager, organizer, e-wallet, radio, media player... –Specialization: different functionality, form factors, power requirements, connectivity, processing and storage, fashion niches  Reducing physical materials within a single device –Modular design should allow configuration on a per-user basis –Similar to PC configuration options but with smaller option units  Device sharing –Example: Environmental impacts of answering machines ~10x more than centralized voicemail (Taiariol, 2001) –But voicemail still lacks features (e.g. live screening) and a good UI

12. Ravi Jain / 19-Sep-02 / 12 Using less: Device sharing on a larger scale  150M hosts connected to the Internet, mostly underutilized –Have been harnessed for tasks that would be impossible otherwise  Mersenne Prime Search (GIMPS): 130K users, 1.5 TFlops –2 13466917 -1 (4M digits), Michael Cameron (Age 20), Canada, 800 MHz PC 13466917  Two key challenges (Anderson & Kubiatowicz, 2001) –Internet Scale Operating System (ISOS) for resource allocation, security … –Economic models to provide private owners with incentives  Additional challenge: take environmental concerns into account –Energy: Preferentially utilize computers in cold regions, or those that are not in dormant mode, or depending on available cycles –Materials: Utilize CPU and storage that would otherwise be wasted  Sharing in enterprise and wireless networks –Pervasive computing environment in user’s home, office, car –Greater device and network heterogeneity, limited resources, restricted UI

13. Ravi Jain / 19-Sep-02 / 13 Using less: Minimizing energy usage  Formal models of energy consumption (Big-oh joules) –Needed to motivate algorithm improvements –Analogy to formal models of disk I/O  Energy-efficient applications and architectures –Example: Half-duplex multiparty calls (“Push-to-talk”) use 50% less power than voice calls  Most 2G/3G systems do not support this feature  Need to consider total-lifecycle energy impacts –Cellphone consumes ~6 kJ/day. Charger: ~110 kJ/day (Nicolaescu, 2001) –Nearly 90% of energy usage in cordless phones and answering machines is in standby mode (U.S. DoE, 2002) –Consider energy consumed in manufacture, distribution, and disposal  Alternative energy sources –Solar energy –Human energy: wrist movement (Citizen eco-drive watch), footfalls can generate 50 mW (Paradiso, 2000), keystrokes

14. Ravi Jain / 19-Sep-02 / 14 Using it longer Programmability  Software Sprawl –SLOC = 13992 e 0.74 yrs R 2 = 0.98 SLOC = Lines excluding comments and blank lines

15. Ravi Jain / 19-Sep-02 / 15 Using it longer Programmability  Software Sprawl Again Office Productivity Suite

16. Ravi Jain / 19-Sep-02 / 16 Using it longer Programmability  Most users do not need all the features of the program (or even know they exist) at any one time  Need mechanisms to –discover system capabilities –discover applications and components –auto-configure software –secure, just-in-time, just-right plug-in upgrades  Hardware requirements should be written not only for entire applications, but based on user-level features  Automated testing techniques need to be developed that support modular hardware  Similar considerations apply to data sprawl

17. Ravi Jain / 19-Sep-02 / 17 Smart disposal  Recent increase in recycling PCs –Manufacturer take-back legislation in US  Cellphone recycling in Japan (Belson, 2002) –Gold: 24 micrograms/phone. Total metal extracted: 21 cents/phone  Crushing devices into their raw materials loses the vast majority of their value  In addition, there are significant health and safety risks of recycling itself …

18. Ravi Jain / 19-Sep-02 / 18 This is not a problem … Source: USA Today 2/25/02

19. Ravi Jain / 19-Sep-02 / 19 Smart disposal  Recycling should focus on –Identifying subassemblies and larger blocks for reuse  RF ID tags –“Upcycling” or remanufacturing into new products  Close the loop of product information –Provide quantitative feedback to designers on actual use, upgrade and failure of software and hardware Product Lifecycle Stage Production Retail Information Associated with Product Consumer Remanufacture Disposal Resale Thomas, 2001

20. Ravi Jain / 19-Sep-02 / 20 Summary  Lower layers –Hardware requirements specification based on user-level features –Modularly upgradeable hardware –Identify subassemblies for recycling –Software radios to adapt to new protocols and air interfaces  OS and system software –Seamless integration of old and new hardware and just-right upgrades –Environmental parameters to an Internet Scale OS –Pervasive OS with environmental design –Minimize OS and software sprawl  Low-cost fault-tolerance techniques –Reduced requirements –Intelligent hardware diagnostics and workarounds –Present surviving resources to apps  Applications support –Minimize data sprawl with better knowledge management, duplicate avoidance, retrieval, and automatic compression –Discover system capabilities, software component discovery and composition, secure, just-in-time plug in –Compiler and automated testing techniques  Applications and UI –Just-right software upgrades –Energy-efficient applications and architectures –Improve UI for device sharing –Make energy and toxic byproducts visible to users:  EnergyStar -> NonToxicStar  Formal models of energy consumption  New design and modeling methodologies  Use and management of alternative energy sources (human, solar)  Environmental impacts need to be treated as a first-class design constraint  If applied consistently, they will have impacts at all levels of software and systems design … a major challenge to integrate total-lifecycle costs into all design aspects

21. Ravi Jain / 19-Sep-02 / 21 Barriers  “A threat to growth / capitalism / our way of life” –Sustainable and environmentally responsible design is the best way to promote long-term growth –Carrots (economic incentives, secondary markets, broker opportunities) are better than sticks (legislation, consumer disaffection)  No immediate short-term benefits –But see NEC Eco PC, Electric cars, etc  Few professional incentives for R&D in this area –National or international R&D funding programs are needed –No workshops, journals or “tenure-friendly” forums and outlets  Research area is difficult: –need multidisciplinary approach (e.g. air bags) –need precise problem formulations –no established benchmarks