This book equips readers with cutting-edge research and practical solutions to thrive in the fast-evolving communications and future internet field. It compiles 15 rigorously reviewed papers from ICCFI 2025, offering actionable insights for academics and practitioners alike. Organized by the University of the Ryukyus, this book captures innovations from ICCFI 2025 (July 11-13, 2025, Okinawa, Japan). Topics span Trojan malware testing, UAV energy efficiency, AI-driven sentiment analysis, and blockchain security--blending engineering principles with real-world needs. It bridges academia and industry, with case studies and interdisciplinary perspectives that turn theoretical concepts into deployable solutions. Essential for anyone shaping the future of communication technologies, this book reflects current trends while anticipating tomorrow's challenges.