Uploaded on 2014-10-13 by St_K

**Visible:** The picture shows a partially residential street in the Brussels area of Ixelles. In the background one office building (European Parliament) is seen. **Invisible:** Electricity is provided through underground cables to all the buildings, the use of smart meter allows for visualizing the consumption pattern as a function of space and time. GSM connections are available in the whole centre of Brussels. GSM data network traffic can reveal the flow of people in the city and the use of urban spaces. [1]: https://edxuploads.s3.amazonaws.com/1413189177958956.jpg