German Chancellor Angela Merkel (C) and Brazilian President Dilma Rousseff (R) visit the IBM exhibition booth at the CeBIT IT fair in Hannover, central north city of Germany, March 6, 2012. Germany's CeBIT, the world's leading expo for information and communication technology (ICT) industry, opened late Monday, focusing on the demanding task of establishing trust and security in the fast-growing digital world. [Xinhua]