FTTX

Technology

Fiber to the Home (FTTH): FTTH is usually deployed in one of two fiber based technologies – either using PON (Passive Optical Networking) technology or P2P with traditional Active Ethernet Fiber. Each Optical Network Terminal (ONT) device at the subscriber premise is connected by a dedicated fiber to a port on a switch in the POP or the optical splitter, using shared feeder fiber to the POP. It uses 100BASE-BX10 or 1000BASE-BX10 transmission in the case of point-to-point connectivity.

Fiber to the Building (FTTB): An Ethernet switch / DSLAM in the building (typically in the basement) is connected to the POP via a single active Ethernet fiber or a pair of fibers, carrying the aggregated traffic of the building via Gigabit Ethernet or 10 Gigabit Ethernet. The connections between subscribers and the building switch can be fiber or copper based and also use some form of Ethernet transport suited to the medium available in the vertical cabling. In some cases building switches are not individually connected to the POP but are interconnected in a chain or ring structure in order to utilize existing fibers deployed in particular topologies and to save fibers and ports in the POP.

Fiber to the Node (FTTN): A switch / DSLAM, typically in a street cabinet, is connected to the POP via a single fiber or a pair of fibers, carrying the aggregated traffic of the neighborhood via Gigabit Ethernet or 10 Gigabit Ethernet. The connections between subscribers and the switch in the street cabinet can be fiber based using either 100Mbps or Gigabit Active Fiber or copper based using VDSL2. This architecture sometimes is also called “Active Ethernet” as it requires active network elements in the field.

Popular Broadband Deployment Types: 66% of the popular broadband access technologies on the left contain optical fiber. Operators have flexibility in deployment when considering distance, cost and the transmission speed and bandwidth demands from customers. From the technology and the green point of view, FTTx proves to be the best, most future-proof solution.

Popular Broadband Access Technologies

Applications

IPTV, a new booming entertainment service provided by telcos worldwide, is made possible by using an Internet protocol over broadband connections. This puts great demands on the underlying infrastructure and networking equipment to be installed in network branching points and at customer premises. The video stream consumes more bandwidth for video transmission and the service is even more sensitive to transmission jitter and delay compared to data exchange or Internet access, so the application relies on a managed high-speed network to guarantee the quality, and FTTx is definitely the best solution to choose.

Types of FTTx: Operators adopt FTTx solutions based on their strategies, development plan and TCO evaluation from different territories. See the table below to compare FTTN, FTTB and FTTH with different dimensions. While PON has become the preferred technology for FTTH in many places of the world, a certain number of deployments in Europe and the Middle East are based on point-to-point fiber (P2P/AE), either for direct connections between subscribers and POPs (Points of Presence) in real FTTH scenarios or between building switches and POPs in FTTB scenarios. It is mainly due to the fact that most of the initial European deployments were made by municipalities which were effectively working in green field scenarios, i.e. they had to invest into civil works which constitutes the dominant part of the cost for deploying FTTH, while the cost of fiber is not a significant factor.

Overview Dimensions FTTx

Operator’s Point of View

Business Approach: Using fiber optic cable promises virtually unlimited bandwidths; however the network operator always only has copper wire line over the last mile. This means that if DSL technology is no longer enough, new optical cables must be laid. The high investment costs of this infrastructure, combined with telecommunications providers’ falling revenue at the same time, mean it is often difficult to put a business case to investors and network providers’ management boards. Nowadays, the ICT industry is spoilt with returns on investment of one to three years. However, when expanding FTTH and FTTC networks (regardless of whether PON or Active Fiber technology is used), it sometimes takes more than five years. Nevertheless, depending on the application and conditions at the time, business cases vary greatly, depending on whether passive or active access technology is used for the plan.

Success Cases: A number of FTTH operations are already profitable. Household penetration has hit 45.3% in Korea and Korean Telecom plans to provide 92% of national coverage by 2010 and 100% coverage by 2015; in Japan 39.5% of FTTH/FTTB in countrywide, 67.7% broadband service household penetration.

Overview of FTTx in different countries