CDMA (Code Division Multiple Access)

Code Division Multiple Access is the air-interface technique used by 2G IS-95 (cdmaOne) and 3G CDMA2000/EV-DO networks, originally championed in North America. Multiple users share the same frequency by being separated through orthogonal pseudo-random code sequences. CDMA networks have largely been migrated to LTE and 5G, and the technology is operationally retired in most markets, though the underlying CDMA principle survives in WCDMA and 5G NR control-channel coding.

Categories: Radio Access NetworkInternet and RoutingEncryption and Cryptography

CDMA in context

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

Telecom networks depend on Internet-style routing (BGP, DNS, MPLS) for interconnect, transport and application delivery. Route hijacks and DNS abuse can degrade or intercept signaling as easily as any application-layer attack, which is why RPKI and DNSSEC are now standard hardening for carrier networks.

To place CDMA in the wider telecom-security picture, review OFDMA, TDMA, OFDM, Carrier Aggregation, Broadband and Network Slicing.

Related terms

Related topic hubs

  • Diameter Security 4G/LTE Diameter threats across IPX/roaming and DEA defenses.
  • Diameter Attacks S6a IDR/PUR/CLR abuse, subscriber tracking, LTE signaling attacks.
  • Open RAN Security O-RAN xApp/rApp, E2/A1/O1 interfaces and RIC security.
  • 5G Security 5G SBA, SEPP, SUCI, 5G-AKA, N32 and service-based interface security.

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.