Modern mobile networks must adapt to rapidly changing traffic patterns and increasing user demands. A key challenge is understanding where user traffic terminates and how these destinations vary over time. This thesis addresses this challenge by introducing an open-source, modular analysis framework that analyzes passive Internet traffic traces, enriches them with geolocation and organizational metadata, and infers latency stability and routing dynamics, in order to characterize the infrastructures that terminate user traffic and assess their performance and reliability over time. The results show a long-term shift towards content-centric traffic, highlight geographic and temporal variations in performance, and demonstrate that content networks typically offer greater stability than enterprise or research destinations. These findings support adaptive traffic management strategies in 5G and future 6G networks.