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 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.

Signaling protocols carry the control-plane messages that set up calls, register subscribers 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 as top-tier telecom risk.

To place Operational Expenses (OPEX) in the wider telecom-security picture, review FS.07, FS.19, GGSN, GTP, GTP Firewall and HLR — each entry cross-references back to this page so you can walk the topic in either direction.

Related terms

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