london year wave denial-of-service attack knock major websites around world millions unsecured printers network gear webcams remain undefended attack across major european cities report publish tuesday say computer security company trend micro 4704.t say berlin 2.8 million insecure devices follow closely london 2.5 million expose gadgets among top 10 capitals rome low nearly 300,000 visible unsecured devices researchers say study base calculate number expose devices major european cities use shodan search engine help identify internet-linked equipment trend micro say electronics users must take responsibility manage internet-connected devices failure many gadget manufacturers build up-front security default products warn come one year wave attack use so-called botnets infect devices cause outages popular websites knock 900,000 deutsche telekom dtegn.de users internet reut.rs/2bjdrii computer experts say failure patch millions insecure devices last year mirai denial-of-service attack mean question time broad-based outages occur research company gartner recently forecast would 8.4 billion connect products devices 2017 31 percent 2016 expect number triple 2020 goo.gl/thr54q millions insecure gadgets expose european cities report