Wired Broadband Technologies
A large range of communication technologies with different technical capacities are capable of providing high-speed internet to households. Wired technologies include copper cable (xDSL), coaxial cable (e.g. HFC) and modern optical fibre cable (FTTx).
Copper wires are defined as “legacy telephone unshielded copper twisted pair”, providing broadband connections by using xDSL-technologies, such as ADSL/ADSL2+ (max. 24/1 down-/upstream rate within max. 5 km efficiency range) or VDSL/VDSL2 (with vectoring max. 100/40 down-/upstream rate within 200 m efficiency range).
- Pros: They require relatively low investment needed for passive infrastructure (a copper telephone line is already present in most households) and are least disruptive for the end users
- Cons: The high (download) speeds depend on the length of copper line. The xDSL technology is heavily asymmetrical: upload speeds are generally much lower than download speeds; this may hamper new services (e.g. cloud computing, videoconferencing, teleworking, tele-presence). Higher investment is needed in active equipment (with a life-time of 5-10 years). An interim solution to invest in fibre infrastructure would most likely only be postponed by 10-15 years.
- Sustainability: New copper-based technologies (e.g.: vectoring, G.fast) can deliver high speeds, but suffer from the same limitations. Bridge technology towards complete fibre optic cable infrastructure.
The classical cable connection would be the two wires of a telephone line (‘twisted pair’), most prone to disturbance effects such as interferences. Broadband internet via coaxial cable is usually offered to customers via the existing cable TV network. The coaxial cable consists of a copper core and a copper-shielding coat. The TV cable networks are therefore much more efficient than the traditional telephone networks.
- Pros: This requires relatively low investment needed for passive infrastructure and is also least disruptive for the end users. This infrastructure offers slightly more opportunities to deliver higher broadband speeds than on telephone lines and, if the infrastructure is properly upgraded and distances kept short, ultra-fast speeds may become possible in short to medium term.
- Cons: The bandwidth is shared among several users reducing its availability during peak traffic periods of the day. The impossibility of unbundling makes service competition basically absent in the cable market; seldom present in the digital-divide areas. An interim solution to invest in fibre infrastructure would most likely only be postponed by 10-15 years as with copper wires.
- Sustainability: Further implementation of new standards (DOCSIS 3.1) will allow for higher bandwidths to end-users
Optical fibre lines consist of cables of glass fibre connected to end-users’ homes (FTTH), buildings (FTTB) or street cabinets (FTTC). They allow for transmission rates of up to several Gbps within 10 to 60 km efficiency range. This is the best solution, requiring high investment in passive infrastructure.
- Pros: Extremely high level of transmission rates and symmetry
- Cons: High investment in passive infrastructure due to the high costs for civil engineering for excavation and piping.
- Sustainability: Next generation technology with capacities to meet high bandwidth demands expected in the near future.
Wired broadband infrastructure deployment is a cost and resource intensive option. Reducing the costs will encourage investments in broadband roll-out and lower the threshold for market entry.
Accessing alternative infrastructures, utilities networks and by using low-impact deployment strategies (such as trenching), wired broadband deployment may be sensibly reduced.
Wireless Broadband Technologies
Antenna sites for wireless connections
A terrestrial wireless broadband connectivity is usually provided by WiMax (4/4 Mbps down-/upstream rate within 60 km efficiency range), Wi-Fi (300/300 Mbps down-/upstream rate within 300 m efficiency range) or 4G/LTE (100/30 Mbps down-/upstream within 3 to 6 km efficiency range) solutions. Further improvements will focus on new standards with additional features and the provision of additional frequency spectrums (5G).
Whenever the upgrade of the wired infrastructure is not possible, and funds for FTTB/FTTH are not available for a certain area, an option is to build infrastructure for terrestrial wireless broadband, mainly antenna sites for point-to-multipoint connections (e.g. WiMax, Wi-Fi, 4G/LTE).
- Pros: First mile wire connections not needed. The infrastructure can be used for commercial mobile services as well
- Cons: Since bandwidth can be shared among several users, peak traffic periods of the day will reduce the available bandwidth for each user. Signal strength decreases fast with distance, and is affected by weather; disturbed line-of-sight may reduce signal quality. Interim solution: investment in fibre infrastructure may be needed within 10-15 years.
- Sustainability: To access future NGA-services, bandwidth needs require additional frequencies; however the available spectrum is limited
Satellite Broadband, also referred to as internet-by-satellite, is a high-speed bi-directional internet connection established via communications satellites instead of a telephone landline or other terrestrial means. Satellites are located in the geostationary orbit. The end customer sends and receives data via a satellite dish on the rooftop.
- Pros: It requires low investment for passive infrastructure as regional backbone and area networks are not needed. It is easy to connect users scattered over a relatively large area (regional, macro-regional or even national).
- Cons: Limited total number of users can be covered in one region. Its inherently high signal latency due to the propagation time to and from satellite hampers certain applications. A relatively high cost of end-user active equipment is needed. Bad weather and limited line-of-sight may reduce signal quality. Data traffic is typically capped monthly or daily in current commercial offers.
- Sustainability: The available bandwidth especially depends on the amount of users that demand the satellite technology. Depending on further development potentials (e.g. transmission methods, satellite constellation), the technology will play a significant role in covering areas that are not yet connected otherwise.
Next generation communication systems will most probably be the first instance of a truly converged network where wired and wireless communications will use the same infrastructure.
5G - converged networks
5G describes the next phase of mobile telecommunications standards beyond the current 4G/LTE. 5G should allow for an application end-to-end latency of 1 milliseconds or less, according to Ericsson white paper 2015. Devices and applications will automatically select the network which best suits their needs. Industry and research expect a commercial roll-out of 5G in 2020. Read more about the latest policy developments concerning 5G in the EU.
Pros: 5G offers improvements in coverage, signalling efficiency, transmission rates (min. 1 Gbps), and reduced latency. Unlike in existing networks, 5G will include many different radio technologies – each optimised for a specific need (e.g. connecting cars, houses and energy infrastructures).
Cons: Most of the current services are not yet in need of such high-speed data transmission rates. This will change as new applications in need of enormous capacities develop. Therefore, high-speed connections provide the basis for which telcos are in charge of upgrading or newly building the required infrastructure.
Vectoring is a transmission method for the VDSL-technology to limit interferences on copper wires (cross talk cancellation). It is fast to install as it builds on the existing street cabinet infrastructure.
Pros: Vectoring offers further transmission and range improvements (100/40 Mbps down-/upstream rate within 200 m and 50 Mbps downstream within 600 m efficiency range).
Cons: Although technically feasible at the moment, vectoring is incompatible with local-loop unbundling but future standard amendments could bring this forward. It can be considered an unsustainable bridging solution.
G.fast and VDSL2 Annex Q
Besides the method of fault rectification through vectoring, in terms of achieving higher bandwidths on copper-based infrastructure, the method is pursued, to transmit signals at a higher frequencies range. G.fast and VDSL2 Annex Q are technologies which reach, in combination with vectoring and the transmission of signals with 35 megahertz (VDSL2 Annex Q) or 100 megahertz and more (G.fast), bandwidths of several hundred Mbps via copper cable, however, only via relatively short distances (aggregate rates of 300 Mbps within 250 m efficiency range). Therefore, this technology is primarily intended to be used for FTTB infrastructures.
The pros and cons of G.fast and VDSL2 Annex Q are similar to those of Vectoring mentioned above.
Low Earth Orbit (LEO) Satellites
Satellites circulating closer to the earth (low earth orbit ranges from about 160 to 2000 km above earth) allow for better web performance, cover wide areas and enable affordable broadband access. Small, low-cost user terminals communicate with satellites and deliver LTE, 3G and WiFi to the surrounding areas.
OneWeb is a company building the world’s largest satellite constellation aiming to launch more than 600 tiny satellites; they are cutting latency from 500 milliseconds to 20 milliseconds.
SpaceX, which already serves the International Space Station, plans to put 4.000 small, low-cost, disposable satellites into orbit. SpaceX's satellites will orbit about 1200 km above the earth to allow for faster internet service. Testing of the technology is expected to begin in 2016.
Pros: Medium Earth Orbit (MEO) and Low Earth Orbit (LEO) satellites are not featuring great delays. They can cover wide areas and thus facilitate broadband coverage for very rural and remote areas.
Cons: A big network of satellites launched in the orbit is necessary to cover wide areas/most of the planet. This in turn produces high costs for the supplying companies, also in terms of the controlling by the necessary ground stations of non-stationary flying satellites.
Internet balloons are sent up 20 km into the stratosphere. Specific software moves them up or down to find the right winds to direct them into position. Each balloon beams an internet connection down to antennas on the ground.
Google’s Project Loon is a network of solar powered balloons transmitting internet signals to ground stations, homes, workplaces or directly to personal devices. Balloons travel on the edge of space, specifically designed to connect people in rural and remote areas. Google is currently scaling up and testing to be able to launch thousands of balloons. Loon is now working towards commercial deals with several network operators.
Pros: Internet balloons are capable of bringing internet access to the most remote parts of the planet.
Cons: Internet balloons are currently in the testing phase; technical hurdles especially concern their shorter durability in the air. However, progress can be seen here, as balloons can already stay up to 6 months. Likewise LEOs, controlling by the necessary ground stations of non-stationary flying balloons is very challenging.
Light Fidelity (LiFi)
LiFi is a bidirectional, high-speed wireless communication technology. It uses visible light communication or infra-red and near ultraviolet (instead of radio frequency waves) spectrum. Light from light-emitting diodes (LEDs) serve as a medium to deliver communication. PureLiFi demonstrated the first commercially available LiFi system, the Li-1st.
Pros: LiFi is 100 times faster than WiFi, reaching speeds of 224 Gbps. The technology is useful in electromagnetic sensitive areas such as in aircraft cabins, hospitals and nuclear power plants without causing electromagnetic interference. Additionally, LiFi is expected to be ten times cheaper than WiFi.
Cons: The technology only delivers communication over a short range. Low reliability and high installation costs are further potential downsides. LiFi can only be used effectively and permanently within closed rooms and with existing sight contact.
Future trends and developments
Research and development increasingly focus on All-internet Protocol Network (AIPN). This allows to improve communication and data transmission via Internet Protocol (IP)-based network technologies and services that include internet telephony or VoIP (Voice-over Internet Protocol).
IP-based data packet transmission allows the development of innovative services and applications independently from the underlying network infrastructure. 5G is a typical example of the convergence of mobile communication and parallel existing broadband network technologies.
Recent developments involve network infrastructures to be complemented by all-optical-networks, which will allow application- and content-routing and switching
A fourth strand of research includes the post-IP type of data transmission, which is characterised by:
- New architecture with management capability supporting multi-domain;
- New wireless-friendly (energy and spectral efficiency) protocols capable of supporting a variety of wireless networks, from very low power sensor networks to wide area mobile networks.
Existing and future transmission rates, innovative methods of data compression and improvements to transmission standards will meet bandwidth-intensive services and applications. It should be noted that the compression method is always lossy in terms of quality of data (e.g. TV-formats, video conferences).