Security Enhancement Of Integrated XGPON/GPON Systems

Abstract

Broadband services demands are rapidly increasing day by day with the explosion of internet applications. The internet services are putting peer pressure on the optical fiber communication channel to provide large bandwidth to the end user. In order to provide high bandwidth per user, cost efficiency, passive optical networks are considered as the optimal solution due to presence of only passive components.Along with the transmission of data, transmission of confidential/sensitive data via passive optical networks is also a great application of optical fiber communication systems. Due to transmission of confidential data over passive optical networks, risk of signal tapping comes into play and is prominent such as in military stations. Signal tapping can be performed with the use of extra sensitive photo-detectors and other low cost components/equipments. Work on physical layer security in PONs is required to cope with network breaching issues by eavesdropper. A forward compatible integrated asynchronous GPON/XGPON is presented by incorporating pseudo random user scheme in this thesis. Both the PON standards are made to work on same optical distribution network and security is increased from optical line terminal as well as optical network units without any tampering with transmission line. Purpose of novel PUS method is to enhance the security of the GPO/XGPON system under the presence of eavesdropper. Comparison of GPON/XGPON system has been done with and without PUS scheme and probability of correct bit detection is analyzed. Further, a secondary case to evaluate the performance of spectral amplitude codes such as Double diagonal codes, Multi-diagonal codes are studied as pseudo user and their performance is observed to hide the authentic information under virtual user. It is evident that system with PUS provides high security and out of DDW, MD codes, cross-correlation based DDW codes are less correctly detectable at eavesdropper receiver.