ADSL uses two pieces of equipment, one on the customer end and one at the Internet service provider, telephone company or other provider of DSL services.
At the customer's location there is a DSL transceiver. The DSL service provider has a DSL Access Multiplexer (DSLAM) to receive customer connections.

Most residential customers call their DSL transceiver a "DSL modem." The engineers at the telephone company or ISP call it an ATU-R. Regardless of what it's called, it's the point where data from the user's computer or network is connected to the DSL line.
The transceiver can connect to a customer's equipment in several ways, though most residential installation uses USB or 10 base-T Ethernet connections.

While most of the ADSL transceivers sold by ISPs and telephone companies are simply transceivers, the devices used by businesses may combine network routers, network switches or other networking equipment in the same platform.

The DSLAM at the access provider is the equipment that really allows DSL to happen. A DSLAM takes connections from many customers and aggregates them onto a single, high-capacity connection to the Internet. DSLAMs are generally flexible and able to support multiple types of DSL in a single central office, and different varieties of protocol and modulation, both CAP and DMT, in the same type of DSL.

In addition, the DSLAM may provide additional functions including routing or dynamic IP address assignment for the customers. The DSLAM provides one of the main differences between user service through ADSL and through cable modems.

Because cable-modem users generally share a network loop that runs through a neighbourhood, adding users means lowering performance in many instances. ADSL provides a dedicated connection from each user back to the DSLAM, meaning that users won't see a performance decrease as new users are added -- until the total number of users begins to saturate the single, high-speed connection to the Internet. At that point, an upgrade by the service provider can provide additional performance for all the users connected to the DSLAM.

A multi-service access node (MSAN), also known as a multi-service access gateway (MSAG), is a device typically installed in a telephone exchange or in a roadside serving area interface cabinet that connects customers' telephone lines to the core network, to provide telephone, ISDN, and broadband such as DSL all from a single platform. Prior to the deployment of MSANs, telecom providers typically had a multitude of separate equipment including DSLAMs to provide the various types of services to customers. Integrating all services on a single node.

When the router is powered up, green lights at the front confirm that the router is switched on and can 'sync' with the external line, but there are no lights to show whether it has been configured properly. A blinking green light shows that a connection is being negotiated. A persistent blinking green light indicates a problem in the connection between the router and the exchange.