CAPEX (Capital Expenditure)

Capital Expenditure is the up-front investment in physical or intangible assets that a telecom operator capitalises and depreciates over multiple years, radio sites, fibre, core network equipment, spectrum licences. CAPEX is balanced against OPEX (recurring operating cost) in business cases; the ongoing shift toward cloud-hosted network functions converts much traditional CAPEX into OPEX.

Categories: Radio Access NetworkCore NetworkSignaling

CAPEX 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.

The mobile core carries subscriber sessions, mobility and policy. 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.

To place CAPEX in the wider telecom-security picture, review MVNO, Vulnerability Management, Risk Assessment, 5G SA, Core Network and Fuzzing: each entry cross-references back to this page so you can walk the topic in either direction.

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