No Limits!

FTTx allows a technology shift from existing copper cabling systems to fiber, providing an almost unlimited transmission rate. Plenty of financial models have shown little difference between the deployment costs of optical fiber and copper cable systems of equal capacity.

FTTx Market Insights

FTTx subscription CAGR 2004 to 2008 worldwide is over 50% on average (Infornetics). The total number of fiber subscribers worldwide is projected to reach 173.8 million by 2013 experiencing a CAGR of 35.5%. From 2008 to midyear 2009, the coverage of FTTH doubled to 6% worldwide.

FTTx Creates Business Opportunities

FTTx operation in Next Generation Access (NGA) services will increase ARPUs reliably by + 30% above DSL (Yankee Group, 2008). Additionally, FTTx revenue is increasing due to cooperations with the entertainment industry where high-quality online services and content are offered. Ultra bandwidth provided by FTTx enables video conferencing and unified communications services for both commercial and residential users.

Driving Force of FTTx

High-definition IPTV is one of the key drivers of FTTx, 2+ simultaneous HD streams for multi-room IPTV services will be the major trend in the coming years. Green environment issues are another driving force because fiber deployment saves more on CO2 than copper deployment.

How FTTx Impacts Our Lives

Just take a look at the friends around you and you can see how all our lives are gradually changing by the booming applications of broadband networking. People at work are using wired/wireless broadband access to the office and remote even for video communications and advanced requirements in e-business (unified communications). People at home are being entertained with HD IPTV and online gaming or people in vertical businesses are using broadband as an effective training tool for e-entertainment (HD IPTV, online gaming): Web 2.0 (fast content upload/download performance), e-health (e-medicine, remote caring), e-government (public services), e-home (remote control surveillance), e-learning (interactive multimedia education), social (virtual reality community), environment (life quality). More and more applications are being developed simply because the bandwidth chain has been broken. In addition, the power of broadband is only just starting to show how our lives will change from the way we communicate to the way we learn and the way we are entertained.

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.


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.

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.

Maximized Bandwidth, Minimized Cost

By choosing a FTTB/FTTN/FTTC architecture, the ISP can build a network which will fulfill customers’ demands for bandwidth and at the same time minimize the costs of implementing the network. An important quality of Zyxel’s fiber and VDSL2 solutions is that they are highly scalable and open for increasing both the number of customers to be serviced and the bandwidth to the individual customer. The great advantage of passive fiber (PON) solutions is that splitters are totally passive and do not require any electricity or maintenance, so it can easily distribute the fibers with less operating or maintenance costs and it can operate in very rugged environments. On the other hand, Zyxel provides P2P/Active Ethernet solutions for telco needs in totally different environments. The advantages of a P2P/AE network are the good bandwidth allocation which is managed to assure maximum bandwidth per subscriber though it may have higher energy consumption and maintenance.


FTTx is an emerging network access solution with almost no limits. Zyxel FTTx solutions provide clients with various combinations of solutions/products carrying different technologies. In FTTN networks operators wish to adapt the service to the most economical point which fiber can reach and which can be used by copper wire to get to all DSL users to retain existing customers without bothering, to provide new service promotion or new customer premises replacement. It is as easy as adding fiber interface line cards to an IP DSLAM if deployed in the fiber ready environment. For places with fewer subscribers, Zyxel’s remote VDSL IP DSLAMs can serve as temperature-hardened devices for an outdoor/street cabinet for strategic plans. They can be deployed for high-speed internet access and IPTV services to expand services and market share to the green field.


Fiber has been pushed to get closer to subscribers for a FTTB solution. Targeting communities with high-density population, the benefit of a Zyxel FTTB solution is to reach the most economic point to subscribers in the basement, providing advanced bandwidth-driven services to subscribers with easy-to-install remote MSAN with scalability and expandability.

A FTTH solution is now commonly used in new buildings; it will be a luxury but limitless solution for now and the future.

Network expandability, power consumption, distance and maintenance are the most important advantages which operators endorse. Zyxel provides three different types of FTTH solutions: an end-to-end P2P/AE solution, a GPON IAD, and an end-to-end GEPON solution to fulfill the requirement of operators.

FTTx is a future-proof solution with almost no limits regarding network bandwidth.

Zyxel provides various solutions for operators to choose to adapt a fiber solution according to the environment. It is not only possible to connect from DSL to fiber, from voice/data to video, but it also provides connections for more experienced users using more advanced applications.

Turning Copper into Gold

Extend copper wire life cycle and fully utilize existing investment to increase the speed and revenue of broadband subscribers.

Fortunately, today most of the world’s broadband subscribers already connect to the Internet through copper lines that were originally deployed for traditional telephone services.

And because of exploding Internet access Telcos have been interested in finding ways to get more bandwidth out of their copper networks. It is an interest that has largely been fuelled by intensified competition from the cable operators and the resulting need for Telcos to start delivering the combination of video, data, and voice services: The Triple Play.

VDSL2 provides up to 100Mbps down/upstream in bandwidth. However, the maximum loop length of such high bandwidth is only about 150m to 500m depending on quality of the copper lines. It is a significant issue to broaden VDSL coverage and roll-out other bandwidth-driven applications.

Actual, an attractive Triple Play service package requires about 50Mbps per household – simultaneously enabling 1 or 2 high-definition television (HDTV) channels, high-speed Internet access, and Voice-over-IP telephony. Main drivers for additional increase of bandwidth will be: the delivery of multiple HDTV, Smart-TV and 3D-TV channels, symmetric HD video conference applications and the increasing popularity of video sharing and social media networks.


DSL operators are facing competition from cable operators offering bandwidth who use DOCSIS 3.0 technology to offer 100Mbps and more downstream bandwidth and 10Mbps upstream bandwidth packages. Additional competition comes from fiber operators using GPON (Gigabit Passive Optical Network) and Active Ethernet technology to offer up to Gigabit bandwidth packages. It is a fact that Internet packages including a higher bandwidth can increase ARPU (Average Revenue Per User). A rapid ROI (Return On Investment) is another key point that will be taken into consideration by DSL operators that will affect their investment in fiber or new DSL solutions.

Benefits of Pair-Bonded VDSL2

There is good news for both DSL service providers and subscribers to DSL service solutions: The pair-bonded VDSL2 solution is able to increase both bandwidth and loop reach. It is the best solution to help DSL operators to solve both the bandwidth competition and deployment coverage issues by upgrading the existing DSL infrastructure whilst reducing investments to a minimum. As the figure below indicates, 2-pair-bonded VDSL2 can offer 100Mbps over up to 600m, 80Mbps over up to 900m and 50Mbps over up to 1,400m. It increases reach by an additional 300 to 600m compared to single pair VDSL2 providing the same bandwidth.




Boosting by VDSL 2 Vectoring

VDSL2 vectoring works on a single pair and is based on the concept of “noise cancellation”, much like the headphones people have started to use increasingly on Rate Reach of VDSL2 and VDSL2 Bonding planes, to reduce or cancel background/ engine noise when listening to music or watching a movie. VDSL2 vectoring calculates the interference between all pairs in a binder, based on the actual signals, and will use this information to generate a noise cancellation signal on each pair, effectively removing all crosstalk. See the figure below.

Due to the amount of calculations involved, vectoring will provide the best results in nodes with a limited number of lines (FTTN or FTTB deployments). The only requirement is that all lines are under full control of a single operator, meaning that there can be no sub-local loop unbundling (Highlander principle: “There can be only one”). Indeed, if the lines belong to multiple operators and are terminated on different nodes, then there is no way to collect all the signal and crosstalk data.

Zyxel End-To-End Solution

Zyxel is now offering an End-to-End pair-bonded VDSL2 solution including an environmentally hardened remote VDSL2 DSLAM and some VDSL2 line cards from our IES-5000/5100/6000 MSAN series with 4/8/12 pair-bonded VDSL2 and pair-bonded VDSL gateways featuring a Gigabit Ethernet WAN interface and 802.11n wireless LAN for up to 300Mbps. In addition, the gateways support HomePNA 3.1 with a data transfer rate of up to 320Mbps. The unified USB port supports print servers, network attached storage appliances (NAS) or Z-Wave wireless device controllers for future Smart Home applications.

Now this gateway solution is added by a pair-bonded integrated access device to include VoIP, 300Mbps wireless LAN and 2 USB ports. An additional Gigabit WAN port and a 4-port Gigabit switch complete the device. Besides that, the gateways can be managed remotely in accordance with TR-069 and TR-104.

The Zyxel pair-bonded VDSL2 solution will not only take broadband access to the next level, it will leverage DSL technology and help service providers to offer a practical platform for user-centric bandwidth-demanding applications. Service providers will be able to use the COE and CPE of VDSL2 bonding with higher bandwidth whilst with ADSL there is the fallback of longer reach to leverage the existing infrastructure in a variety of deployment situations to fulfill customers’ needs.

The next technology step will be in 2012 depending on a chipset vendor having a vectoring solution ready for customers.