Optical fiber access networks enable the transmission of large bandwidths over long distances, with performance generally assessed using the bandwidth-distance product. As bandwidth consumption continues to double approximately every two years, optical fiber remains the most sustainable solution for high-speed connectivity. This growing demand has driven significant investment in fiber-to-the-“X” (FTTX) technologies, including FTTN, FTTC, FTTB, FTTH, and FTTP. The advancement of broadband infrastructure, particularly Next-Generation Access (NGA) networks, is increasingly reliant on FTTX solutions to support bandwidth-intensive applications. From a network topology perspective, FTTX deployments fall into two main categories: Point-to-Point (P2P) and Point-to-Multipoint (P2MP) architectures. P2P configurations provide dedicated fiber connections from the central office to individual endpoints, often incorporating active Ethernet nodes. In contrast, P2MP architectures leverage passive optical splitters to distribute bandwidth among multiple users, forming Passive Optical Networks (PONs). This chapter examines these network architectures, their benefits, and their role in enabling the future of high-speed, low-latency communication.