DSLAM

Depending on its device architecture and setup, a DSLAM aggregates the DSL lines over its Asynchronous Transfer Mode (ATM), Frame Relay, and/or Internet Protocol network, i.e., an IP-DSLAM using Packet Transfer Mode - Transmission Convergence (PTM-TC) protocol(s) stack.

Customer-premises equipment that interfaces well with the DSLAM to which it is connected may take advantage of enhanced telephone voice and data line signaling features and the bandwidth monitoring and compensation capabilities it supports.

This compensation capability also takes advantage of the better performance of "balanced line" DSL connections, providing capabilities for LAN segments longer than physically similar unshielded twisted pair (UTP) Ethernet connections, since the balanced line type is generally required for its hardware to function correctly.

The following is a rough guide to the relation between wire distance (based on 0.40 mm copper and ADSL2+ technology) and maximum data rate.

On the upstream trunk (ISP) side many early DSLAMs used ATM—and this approach was standardized by the DSL Forum—with Gigabit Ethernet support appearing sometime later.

[citation needed] IP-DSLAM stands for Internet Protocol Digital Subscriber Line Access Multiplexer.

The advantages of IP-DSLAM over a traditional ATM DSLAM are that the merged equipment is less expensive to make and operate and can offer a richer set of features.