Shaddi Hasan

Syed Tauhidun Nabi, Jocelyn Bliton, Tijay Chung et al.

IP geolocation databases are widely used in research, policy, and industry, yet their accuracy across network types and geographies remains poorly characterized. We present a large scale evaluation of four major providers (MaxMind GeoLite2, IPinfo, IP2Location, and DB-IP) using ground truth from RIPE Atlas and UNICEF Giga across 175 countries. We find that mobile networks exhibit median errors more than 10 times higher than fixed networks across all providers (179--207~km vs.\ 3--16~km), and that Global South regions show significantly higher failure rates than Global North: Asia exceeds 53--61\% and Africa 66--72\%, compared to 9--20\% in Europe. We trace both gaps to a shared structural source: provider prefixes in mobile networks and Global South geographies are more likely to be coarser than BGP announcements, and approximately 70\% of mobile prefixes span more than 100~km geographically. Our findings point to prefix granularity as a common explanatory factor: coarser prefixes consistently produce the highest errors regardless of provider, network type, or geography.

Wesley Woo, Zhuowei Wen, Monniiesh Velmurugan et al.

Since their creation, cellular networks have made in-network mobility support a key feature of their service model. While this approach provides seamless connectivity for legacy traffic, it has the side effects of inflating end-user latency and increasing complexity and operational overhead for operators. Yet modern applications and transport protocols are increasingly mobility tolerant, prompting us to revisit the assumption that mobility must be provided as an in-network service. In this paper, we propose EnCoR (End-to-End Core and RAN), a deployable cellular network architecture that removes mobility from the core entirely. Leveraging end-to-end mobility, EnCoR eliminates tunnel-based IP anchoring while preserving compatibility with existing authentication, charging, and QoS techniques. We demonstrate that EnCoR works with unmodified phones while providing equivalent performance as traditional LTE networks for real applications including video and voice calling and video streaming. We show that EnCoR not only allows network operators to reduce end to end latency, but can also reduce the capital cost of providing low latency service to users by more than 90% compared to 3GPP networks, based on cost estimates for cellular network core and border router infrastructure provided by the FCC. Finally, we demonstrate that these gains are achieved while reducing the amount of overall handover control messaging, allowing the EnCoR core network to handle a greater number of mobility handover events than an LTE core under identical hardware constraints, achieving a 2.6x lower handover latency under load.