Chai Keong Toh

Chai Keong Toh FREng is a Singaporean computer scientist, engineer, industry director, former VP/CTO and university professor. He is currently an Expert Consultant to the Gerson Lehrman Group.[1] He was formerly Assistant Chief Executive (Engineering & Technology) of Infocomm Development Authority (IDA) Singapore. He has performed research on wireless ad hoc networks, mobile computing, Internet Protocols, and multimedia for over two decades. Toh's current research is focused on Internet-of-Things (IoT), architectures, platforms, and applications behind the development of smart cities.[2]

Chai Keong Toh

Chai K Toh.JPG
Toh (on the right) at IET Awards Ceremony in London.
Born1965 (age 57–58)
Alma materUniversity of Cambridge
University of Manchester
Known forComputer networks, mobile computing, ITS, data analytics, IoT and Smart Cities
AwardsIEEE Kiyo Tomiyasu Award (2005)
IET Achievement Medals (2009)
IEEE Fellow (2009)
AAAS Fellow (2009)
IET Fellow (2004)
BCS Fellow (2003)
FREng (2019)
Scientific career
InstitutionsNational Tsing Hua University
University of London
ThesisProtocol Aspects of Mobile Radio Networks (1996)
Academic advisorsAndy Harter (examiner)
David Wheeler (mentor)
Jean Bacon (mentor)
WebsitePersonal website

Early lifeEdit

Born in Singapore, Toh studied in Singapore Polytechnic[3] and then received his university education in the United Kingdom. He subsequently moved to live and work in the United States. He studied at King's College, Cambridge under a Cambridge Commonwealth Trust Scholarship, and received his Ph.D. in computer science from University of Cambridge, UK in 1996 and his undergraduate EE degrees at the University of Manchester Institute of Science and Technology in 1991.

Industry, public sector and universitiesEdit

From 2002 to 2004, Toh was the Director of Research,[4] Communication Systems, at TRW Systems Corporation (now Northrop Grumman Inc) in Carson, California. After his PhD in 1996, he joined Hughes Research Laboratories in Malibu, California.[5] At Hughes, he co-led the DARPA TTO DAMAN (Deployable and Adaptive Mobile Ad Hoc Networks) Program. Earlier on, he worked as an engineer at Advanced Logic Research Computers, Archive Corporation, and served on the technology advisory board of Convergence Corporation (acquired by Amazon[6]).

Since 2011, he has been appointed the Tsing Hua Honor Chair Professor of Computer Science (Taiwan).[7] He has also been an Honorary Professor at the University of Hong Kong,[8] China (2004–2009), Honorary Professor at the University of Essex,[9][10] UK (2013–2015), Honorary Professor at the University of Haute Alsace, FRANCE (2013), and Advisory Professor of Computer Science[11] at Technical University of Valencia, SPAIN. Earlier on, he was a tenured Chair Professor at the University of London (2004–2006)[12] and on the faculty at University of California, Irvine[13] and at Georgia Institute of Technology.

In 2014, Toh was appointed as Assistant Chief Executive (Engineering And Technology), of Infocomm Development Authority of Singapore (IDA) in 2014.[14][15] He was concurrently the Chief Engineering & Technology Officer (CETO) of IDA.[16] He left Infocomm Media Development Authority (formerly known as IDA)[17] and joined Singapore Power Telecom Ltd as VP and CTO.[18]

Inventions and awardsEdit

Toh was as an IEEE Expert Lecturer[19] of the IEEE Communications Society from 2002 to 2003. He is also listed among the top 20 authors[20] in Wireless/Mobile Networks in the world by THOMSON Essential Science Indicators (ESI) for technical papers published from 1995 to 2005. His and Publish or Perish total citation exceeds 20,000.[21] Subsequently, he returned to United States.

Toh also invented Associativity-Based Routing and Wireless Mobile Ad Hoc Networks (Wi-Fi Ad-Hoc Mode).[22][23] His first successful implementation of Wi-Fi Ad-Hoc Mode was achieved in 1998 when he established a working wireless ad hoc network in Georgia, USA.[24][25][26] In 2009, he challenged the "always-on" Internet model, claiming that the resulting energy burden globally is not sustainable. Instead, he advocated re-designing existing Internet architecture, routers, switches, servers and data centers.[27] In 2011, he invented a method to identify witnesses during car accidents using a distributed information dissemination and data fusion approach.[23] In 2009, he introduced "signs that talk", transforming traffic signs into wireless digital forms[28]

He is an elected Fellow of the IEEE (FIEEE),[29] a Fellow of the American Association for the Advancement of Science (FAAAS),[30] Fellow of the British Computer Society (FBCS), Fellow of IEE (Institution of Electrical Engineers),[31] Fellow of HKIE Hong Kong Institution of Engineers, Fellow of IITP (Institute of IT Professionals - formerly known as New Zealand Computer Society),[32] Fellow of Cambridge Commonwealth Society,[33] and Life Fellow of the Cambridge Philosophical Society, UK.[34] He is a Chartered Engineer (UK) and Chartered IT Professional (CITP).

In 2005, IEEE awarded him the IEEE Institution Kiyo Tomiyasu Technical Field Award,[35] with the citation – "for pioneering contributions to communication protocols in ad hoc mobile wireless networks". He has undertaken research in wireless ad hoc networks since 1993 (while at Cambridge University) and had written two sole-authored pioneering books: "Wireless ATM & Ad Hoc Networks"[36] (Kluwer, 1997) and "Ad Hoc Mobile Wireless Networks"[37] (Prentice Hall Best Seller, 2001). In 2009, IET awarded him the John Ambrose Fleming Medal (IET Achievement Medals) in London.[38][39] In 2019, he was elected to the Royal Academy of Engineering, UK.[40]



  • Toh, Chai Keong (2001). Ad Hoc Mobile Wireless Networks: Protocols and Systems - Prentice Hall Best Seller 2002. Pearson Education. ISBN 9780132442046. - also published in Japan (Japanese translation) and India (paperback edition)
  • Toh, Chai Keong (1997). Wireless ATM and Ad Hoc Networks: Protocols and Architectures. Kluwer Academic Publishers. ISBN 978-0792398226.
  • Toh, Chai Keong (1996). Protocol Aspects of Mobile Radio Networks. University of Cambridge.

Noted papers/patentsEdit

Keynotes and mediaEdit


  1. ^ "King's alumnus elected as a Fellow of the Royal Academy of Engineering". King's College Cambridge. Retrieved 13 October 2021.
  2. ^ Toh, Chai K. (2020). "Security for smart cities". IET Smart Cities. 2 (2): 95–104. doi:10.1049/iet-smc.2020.0001.
  3. ^ "Giving back to his alma mater once again | News | EEE". Retrieved 13 October 2021.
  4. ^ "TRW Adds Boeing to Team in Pursuit of Warfighter Information Network-Tactical Contract". Archived from the original on 20 December 2016. Retrieved 15 December 2016.
  5. ^ Toh, C.-K. (1 July 1997). "Wireless". ACM SIGMOBILE Mobile Computing and Communications Review. 1 (2): 6. doi:10.1145/583982.583988. S2CID 1070824.
  6. ^ " Acquires Convergence Corporation". Archived from the original on 25 September 2017. Retrieved 30 March 2017.
  7. ^ "Chai K. Toh - Engineering and Technology History Wiki". 19 October 2020.
  8. ^ Toh, C. K. (2007). "Guest Editorial Special Section on On-the-Road Mobile Networks". IEEE Transactions on Intelligent Transportation Systems. 8 (3): 378. doi:10.1109/TITS.2007.907049.
  9. ^ "Honorary Professor, University of Essex". Archived from the original on 20 December 2016. Retrieved 15 December 2016.
  10. ^ "Professor CK Toh awarded Honorary Professor of University of Essex". Archived from the original on 20 December 2016. Retrieved 16 December 2016.
  11. ^ "Web site at Technical University Valencia, SPAIN".
  12. ^ "Advanced Topics on Ad Hoc Mobile Wireless Networks".
  13. ^ "NSF Award Search: Award#0241006 - Wireless Technology: Issues on QoS Stability, Sensitivity, Flow & Congestion Control in Wireless Broadband Networks".
  14. ^ "EMTechAsia - Influential thinkers and innovators, 2015". Retrieved 1 January 2017.
  15. ^ "IDA Appoints New Assistant Chief Executive (Engineering And Technology)". Retrieved 24 May 2020.
  16. ^ "MEDIA RELEASE Transforming Businesses through GS1 Standards" (PDF). 7 October 2015. Retrieved 27 May 2020.
  17. ^ "Internet of things gains momentum in Southeast Asia". Retrieved 13 October 2021.
  18. ^ "Bio data of Chai K Toh, IEEE, 2022".
  19. ^ "The Ring, Page 6" (PDF).
  20. ^ "Emerging science trends - Essential Science Indicators".
  21. ^ "Chai K Toh FREng (CTO/VP/Professor) - Google Scholar Citations".
  22. ^ "Routing method for Ad-Hoc mobile networks".
  23. ^ a b "Method and system for disseminating witness information in multi-hop broadcast network".
  24. ^ Chapter 7 - Implementation of Ad Hoc Wireless Networks, in book "Ad Hoc Mobile Wireless Networks: Protocols & Systems" by Toh
  25. ^ Implementation and Evaluation of An Adaptive Routing Protocol for Infrastructureless Mobile Networks, Proceedings of IEEE ICCCN Conference, 2000
  26. ^ Mobile Computing Magazine Interview Article on Mobile Ad Hoc Networks Implementation, 1999. (PDF)
  27. ^ "Green Internet - Dated 2009". 2 November 2016.
  28. ^ "Wireless Digital Traffic Signs of the Future, CK Toh, JC Cano, CJ Fernandez-Laguia, P Manzoni, C Calafate, IET Networks 8 (1)" (PDF).
  29. ^ "IEEE - Fellows - Institution of Electronic & Electrical Engineers". IEEE. Archived from the original on 23 September 2013. Retrieved 22 May 2013.
  30. ^ "Fellows - American Association of Advancement of Science". Archived from the original on 27 July 2014.
  31. ^ "Fellows - Institution of Electrical Engineers". IEE.
  32. ^ "Fellows -Institute of IT Professionals (New Zealand Computer Society)". IITP. Archived from the original on 29 April 2013. Retrieved 24 May 2013.
  33. ^ Cambridge University Commonwealth Society, archived from the original on 30 November 2016, retrieved 29 November 2016
  34. ^ "Fellows - Cambridge Philosophical Society". Cambridge Philosophical Society.
  35. ^ "IEEE Kiyo Tomiyasu Award Recipients".
  36. ^ Toh, C. K. (1997). Book - Wireless ATM & Ad Hoc Networks, 1997, Klueer Academic Publishers. ISBN 9780792398226.
  37. ^ Toh, Chai K. (3 December 2001). Book - Ad Hoc Mobile Wireless Networks: Protocols and Systems, 2001, Prentice Hall Publishers. ISBN 9780132442046.
  38. ^ "IET Achievement Medals". Archived from the original on 29 March 2016. Retrieved 22 March 2016.
  39. ^ "Full Page Reload". IEEE Spectrum: Technology, Engineering, and Science News.
  40. ^ "Academy welcomes leading UK and international engineers as new Fellows - Royal Academy of Engineering".
Preceded by IET Ambrose Fleming Medal (IET Achievement Medals)
Succeeded by
Preceded by IEEE Kiyo Tomiyasu Award
Succeeded by