Kyushu University, Japan on "Cybersecurity" (2016)
University of Maryland, Baltimore County, USA on "Wireless and Mobile Security" (2015).
Tallinn University of Technology, Tallinn, Estonia on "Cybersecurity and Cyber Systems" (2014).
Technical University of Darmstadt, Darmstadt, Germany on "Advanced Information Theory for Bio Informatics" (2011, 2012).
UNIK, University of Oslo, Norway on 'M2M Project' (2009, 2010).
Institute for High Frequency Techniques, Technical University of Darmstadt, Darmstadt, Germany on "Broadband Wireless Access Technology" (2001, 2002, 2004, 2006).