Operational Expenses (OPEX)

Operational Expenditure is the recurring cost of running a telecom network, electricity, cooling, facility leases, staff, software licences, maintenance contracts, interconnect fees. OPEX is balanced against CAPEX (one-off investment) in business planning, and the move from on-premises hardware to cloud-hosted network functions is largely a CAPEX-to-OPEX shift.

Categories: Core NetworkSignalingRoaming and Interconnect

Operational Expenses (OPEX) 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.

Signaling protocols carry the control-plane instructions that set up calls, register subscribers, hand over sessions and route SMS. SS7, Diameter, GTP-C and SIP are the four dominant families, and interconnect exposure of any of them is treated by GSMA FS.11 / FS.19 / FS.20 as a top-tier telecom risk.

To place Operational Expenses (OPEX) in the wider telecom-security picture, review CAPEX, Red Team Exercise, GTP-U Smuggling, Lateral Movement (Telecom), FS.20 and FS.21.

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