P-CSCF (Proxy Call Session Control Function)

P-CSCF in context

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.

Security controls in telecom span signaling firewalls (SS7/Diameter/GTP screening at the network edge), transport encryption (IPsec, TLS, PRINS), identity and access on OSS/BSS, and monitoring at both the packet and log level. Controls are audited against GSMA FS.11/FS.19/FS.20/FS.36 and, in Europe, NIS2 sectoral rules.

To place P-CSCF in the wider telecom-security picture, review Integrity, Signaling Firewall, Trunk, MGCF, Satellite Backhaul and Diameter Interconnect Security.

Related terms

• Integrity
• Signaling Firewall
• Trunk
• MGCF
• Satellite Backhaul
• Diameter Interconnect Security
• Indicators of Compromise (Telecom IoCs)
• SS7 Interconnect Security

Equipment

IMS core (CSCF, TAS, MRF, MGCF, BGCF)

• BGCF
• CSCF
• E-CSCF
• I-CSCF
• IMS
• IMS-AKA
• IR.92
• IR.94
• MGCF
• MTSI
• All 14 terms

Articles in the P1 mobile network security guide

Related topic hubs

• VoLTE Security IMS/VoLTE signaling risk: SIP, IMS-AKA, media plane attacks.
• IMS Security Training Training on IMS, VoLTE/VoNR, SIP and RCS security.
• Diameter Attacks S6a IDR/PUR/CLR abuse, subscriber tracking, LTE signaling attacks.
• Signaling Firewall Unified SS7/Diameter/GTP/SMS signaling firewall framework.

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.