DSL (Digital Subscriber Line)

Digital Subscriber Line is the family of technologies that deliver broadband over copper telephone pairs, including ADSL, VDSL, SDSL, and G.fast. DSL services share the existing local loop with voice and use frequency-division multiplexing to keep them separate. DSL is being progressively replaced by FTTH and fixed wireless, but remains common in many markets.

Categories: Radio Access NetworkIdentity and SubscriberInternet and Routing

DSL in context

The radio access network is where mobile devices attach to the operator's infrastructure. Attacks in this layer include IMSI catching, rogue base stations and downgrade attacks; defenses rest on mutual authentication, integrity-protected signaling and Open RAN supply-chain hygiene.

Subscriber identifiers (IMSI, SUPI, MSISDN, IMEI) anchor authentication, charging and lawful interception. Any protocol that leaks a permanent identifier is treated as a privacy defect, which is why 5G introduced SUCI concealment on the air interface.

To place DSL in the wider telecom-security picture, review 2G, ADSL, A5/3, AKA, Authentication and Broadband — each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

More from the TelcoSec Glossary

Browse the full TelcoSec Glossary, the Ultimate Guide to Mobile Network Security, or the P1 Arsenal of telecom-security tools.