Due totheincreasing need of privacyin variousinfor-mation exchange situations ,the study on secure com-municationis currently meeting a growinginterest .It isno surprise that optical fibers have been touted as themost affordable and efficient mediumin the field of se-cure communications due to its electrical isolation,itsi mmunitytointerference,anditsi mprovedsignal secur-ity. However ,it has now been shown that fibers leaklight when it is bent to small radius ,and such bendshave been used as …