SDSL (Symmetric Digital Subscriber Line)

SDSL in context

The mobile core is where subscriber sessions, mobility and policy live. In 4G it is the EPC (MME, HSS, S/PGW); in 5G it is the Service-Based Architecture with AMF, SMF, UPF, AUSF, UDM and the NRF. Core exposure is the difference between a single-subscriber leak and a fleet-wide breach.

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

To place SDSL in the wider telecom-security picture, review HDSL, DSL, FDD, PDN, PGW and SRI.

Related terms

• HDSL
• DSL
• FDD
• PDN
• PGW
• SRI
• SIM Box
• Cryptography

Related topic hubs

• Diameter Attacks S6a IDR/PUR/CLR abuse, subscriber tracking, LTE signaling attacks.
• Diameter Security 4G/LTE Diameter threats across IPX/roaming and DEA defenses.
• LTE Security Training Training on 4G/LTE core, Diameter, NAS and RRC security.
• Tracking Area Update LTE TAU procedure and its signaling risks.

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.