DSLAM in IT Glossary

Short for Digital Subscriber Line Access Multiplexer,
a mechanism at a phone company's central location that
links many customer DSL connections to a single high-speed ATM line.

When the phone company receives a DSL signal,
an ADSL modem with a POTS splitter detects voice calls and data.
Voice calls are sent to the PSTN, and data are sent to the DSLAM,
where it passes through the ATM to the Internet,
then back through the DSLAM and ADSL modem before
returning to the customer's PC.

More DSLAMs a phone company has, the more customers it can support.