ADSL2+ (Asymmetric Digital Subscriber Line 2+) is a broadband technology that provides high-speed internet over standard telephone lines. Here’s a detailed look at how it works:
-
Telephone Line Utilisation: ADSL2+ uses existing copper telephone lines provided by Openreach, enabling internet access while still allowing you to use your phone line for voice calls. The technology divides the telephone line into separate frequency bands—lower frequencies for voice and higher frequencies for data.
-
DSLAM (Digital Subscriber Line Access Multiplexer): At the local telephone exchange, a DSLAM is responsible for managing ADSL2+ connections. It collects high-frequency data signals from multiple ADSL2+ lines, aggregates them, and forwards the combined data to the internet backbone. The DSLAM also processes and optimises the signals to ensure stable performance for each connection.
-
Modem/Router: To connect to ADSL2+, you need an ADSL2+ modem or a router with built-in ADSL2+ support. This device modulates and demodulates the signals transmitted over your telephone line, converting them into a format that your devices can use for internet access.
-
Speed and Distance: The performance of an ADSL2+ connection is influenced by the distance from your home to the local telephone exchange. Typical speeds can reach up to 24 Mbps downstream and 1.4 Mbps upstream, but actual speeds can vary based on line length:
- <1 km from the exchange: Speeds up to 20-24 Mbps.
- 1-2 km from the exchange: Speeds around 10-20 Mbps.
- 2-3 km from the exchange: Speeds around 5-10 Mbps.
- >3 km from the exchange: Speeds may drop below 5 Mbps.
-
Openreach Infrastructure: Openreach manages the UK’s telephone network infrastructure, including the copper lines used for ADSL2+ and the equipment necessary for broadband services. They ensure that these lines and DSLAMs are well-maintained to provide reliable internet connections.
In summary, ADSL2+ utilises existing telephone lines and DSLAM technology to deliver internet services, with speeds influenced by the distance from the exchange. The further you are from the exchange, the lower your connection speed may be.
