Security analysis of an image encryption algorithm based on Blowfish in GPON

Abstract Optical access network security concerns are increasingly urgent as the demands of important network functions have been significantly increased. This study evaluates gigabit passive optical networks (GPON) security and provides an innovative, resilient solution. In accordance with the International Telecommunication Union-Telecommunication (ITU-T) G.984.6 standard series, the approach allows for safe mutual authentication and establishment of keys between optical line termination (OLT) units and optical network units (ONUs) in an optical distribution network (ODN). The Blowfish cipher algorithm has been used in combination with the Opti-System software. Fiber to the home (FTTH), based on GPON technology, offers cost-effective triple-play services. Aside from the customer premises and central office, it operates entirely on passive equipment. Telecom operators support FTTH systems based on GPON because they are flexible in reacting to future technologies as well as services. A network with a maximum reach of 65 km can accommodate up to 64 users using secure GPON technology at a minimum acceptable quality factor of 6, a maximum BER level of about 10 −9 and optimum reach between optical consecutive network terminals of 20 km in accordance with G.984.6 ITU-T requirements. GPON transmits 2.5 Gbps downstream (D/S) and 1.25 Gbps upstream (U/S) data transmission with a minimum allowable receiving sensitivity of −35.8 dBm for uplink and −34.3 dBm for downlink has been achieved.