Energy consumption of telecommunication access networks

2 Scope As the introduction shows, broadband internet access is already one of the key requirements for our social and economic wealth and it will be an integral part of the foundation of the global system in the near future. Therefore, broadband networks, which provide the transportation capacities for all services, are needed. These broadband networks can be separated into three major layers: 1. Core network 2. Regional networks 3. Access networks The core network connects continents, countries and major national network nodes. It is based on fibre optic links with data rates up to several GBit/s and the least possible delay. It also provides the data exchange between the network operators (network interconnection), so that every host is reachable. The core network is constantly improved by the ICT companies and can provide the capacities needed to ensure the usage of all internet services. The regional networks connect all access networks with the core network. From a technological perspective, these regional networks do not differ much from the core network. However, they do not provide any network interconnection between different network operators. Broadly speaking, regional networks are just connection lines. The growing demand for internet connection bandwidth however, leads to increasing requirements placed on the regional network infrastructure. The number of regional network connections is far too small to fulfil these requirements. In this context, regional networks can represent a bottleneck in more rural areas. An access network, also referred to as last mile, is the direct connection between the network operators’ local office and a single subscriber. Usually it uses a different transmission technology and infrastructure to the regional network or the core network. In most countries the type of access network technology which is used today depends also on which infrastructure existed in the late 1990s. In Germany and many other countries of the European Union the telephone twisted pair networks were widely spread. As a result, DSL (Digital Subscriber Line) is the most common access technology in the EU. The coax networks for television and radio broadcasting also exist in many European countries. Since the operators implemented DOCIS and adopted their broadcast coax networks into hybrid fibre coax networks, internet connections are also available over this infrastructure. In addition to these two wired technologies, other wired and radio-based access technologies exist. However, they have not gained the importance of DSL and DOCSIS. Since telecommunication companies like Deutsche Telekom introduced broadband connections for the mass market, especially the customers’ demands on data rate is constantly increasing. To address these increasing demands, the existing technologies have been developed further. The deployment of these improved technologies however, has not progressed in every section because network operators’ economic considerations prevented this. As a result, the access networks are the bottlenecks of our time. The network operators and the European governments concentrate their efforts on building up broadband access networks. In the last decade, several billion euros – private capital and public subsidies – were invested into this sector, which causes the installed access networks to transform very rapidly. Hence, this survey is focussing on broadband access networks and their power consumption. The following access technologies will be addressed in detail: • VDSL2 Vectoring • DOCSIS 3.0 in HFC networks at 864 MHz • FTTH – PtP Ethernet • FTTH – GPON 4