Asynchronous digital subscriber line

Asynchronous Digital Subscriber Line (ADSL) is a technology used for transmitting digital data over existing telephone lines. Here are some key points about ADSL:

1. Asymmetrical Speeds: ADSL offers different upload and download speeds, with download speeds typically higher than upload speeds. This is useful for activities like browsing and streaming, which usually require more download bandwidth.

2. Frequency Division: ADSL uses frequency division multiplexing to separate voice and data signals. This allows users to make phone calls while using the internet simultaneously.

3. Distance Limitations: The performance of ADSL degrades over longer distances from the service provider's central office. It works best within a few kilometers of the exchange.

4. Installation: ADSL requires a modem at the user's end and a compatible DSLAM (Digital Subscriber Line Access Multiplexer) at the service provider's end.

5. Applications: It is commonly used in residential settings for internet access, as well as in small businesses.

ADSL has largely been supplanted by faster technologies like VDSL and fiber-optic connections, but it remains in use in areas where newer infrastructure is not available.