| This thesis presents the details of design and analysis of a new solution to the location determination problem of VoIP users. This problem has such a great importance in the emergency cases that without a solution for it, supporting the emergency calls in IP telephony is impossible. We propose an efficient and accurate mechanism, based on a link layer protocol, named Link Layer Discovery Protocol for Media Endpoint Devices (LLDP-MED). In our solution, the first level LLDP-MED capable switches, provide location information based on the LLDP databases. Since providing location information in our solution is performed by the switches, it prevents presenting fake information by malicious users. We also study and evaluate the performance of an exiting solution to this problem which uses Location Information Server (LIS). Then we compare this solution with our proposed mechanism in different aspects, with emergency case considerations. Our simulation results prove that the delay of our proposed technique is much lower than the delay of the solution based on LIS. |
