58 ITU‐T's Technical Reports and Specifications Source Definitions Keywords Hitachi. \"Smart Sustainable City Overview.\" Smart Cities: Hitachi. Hitachi, Web. Last accessed 9 Feb. 2014. http://www.hitachi.com/products/smartcity/vision/concept/overview .html. Hitachi's vision for the smart sustainable city seeks to achieve concern for the global environment and lifestyle safety and convenience through the coordination of infrastructure. Smart Sustainable Cities realized through the coordination of infrastructures consist of two infrastructure layers that support consumers' lifestyles together with the urban management infrastructure that links these together using information technology (IT). Coordinated infrastructure, lifestyle safety, lifestyle convenience, urban infrastructure, IT. Meijer, Albert, and Manuel Pedro Rodríguez Bolívar. \"Governing the Smart Sustainable City: Scaling‐Up the Search for Socio‐Techno Synergy.\" T EGPA 2013 (Edinburgh, September) Permanent Study Group on E‐Government, 2013, Web. Last accessed 8 Feb. 2014. https://www.scss.tcd.ie/disciplines /information_ systems/egpa/docs/2 013/BolivarMeijer.pdf \"We believe a city to be smart when investments in human and social capital and traditional (transport) and modern (ICT) communication infrastructure fuel sustainable economic growth and a high quality of life, with a wise management of natural resources, through participatory governance.\" ICT, high quality of life, natural resource management,participatory governance, transport infrastructure, communication infrastructure, economic growth, sustainability. IBM. \"India Needs Sustainable Cities.\" IBM SMARTER PLANET, Web. Last accessed 6 Feb. 2014. http://www.ibm.com/smarterplan et/in/en/sustainable_ cities/ideas/ . Replacing the actual city infrastructures is often unrealistic in terms of cost and time. However, with recent advances in technology, we can infuse our existing infrastructures with new intelligence. By this, we mean digitizing and connecting our systems, so they can sense, analyse and integrate data, and respond intelligently to the needs of their jurisdictions. In short, we can revitalize them so they can become smarter and more efficient. In the process, cities can grow and sustain quality of life for their inhabitants. Technology, connecting systems, analyse data, integrate data, responsive, efficient, growth, quality of life, sustainability. 5 Results 5.1 Keyword analysis from definitions All the definitions (listed on Annex 1) were analysed to identify the top keywords and characteristics that make a smart sustainable city. Some words such as \"smart\" and \"city\" are implicit and mentioned in almost every description, and hence these words have not been captured explicitly as a separate keyword. A total of 50 keywords were identified which appeared to have multiple references across all the studied definitions. There were a total number of 726 instances of these 50 keywords. These are captured and presented below in a table to reflect the relative contribution/number of times that these keywords were repeated across all the 100+ definitions. Based on the literature review, a graphical representation of the relative importance of the different keywords was developed. The larger the font is, the more important the word is.