Netwerksignalering

Netwerksignalering, or network signaling, is the process of exchanging control information necessary to establish, manage, and terminate communications and services across a network. It is separate from the user data that makes up the actual content of calls or sessions, and it operates on a signaling plane alongside the data plane.

Signaling enables a range of functions, including session setup and teardown, resource allocation, routing decisions, authentication, charging, mobility management, and feature control. It supports both traditional circuit-switched networks and modern IP- and mobile-based infrastructures, enabling services such as voice calls, messaging, and data sessions.

Two broad approaches characterize signaling architectures: out-of-band signaling, where control information travels on a separate channel, and in-band signaling, where control data may be carried with or alongside user data. In practice, networks combine specialized signaling networks with centralized or distributed control functions to ensure reliability and scalability.

Common signaling frameworks and protocols include:

- Traditional telephony: Signaling System No. 7 (SS7) with ISUP, SCCP, and MAP, often deployed with signaling transfer points (STPs) for inter-network communication.

- IP-based networks: Session Initiation Protocol (SIP) for session setup, along with related protocols such as H.323 in some environments, and media gateways.

- Authentication and authorization: Diameter and RADIUS for control plane access in modern networks.

- Mobile networks: CAMEL and MAP in earlier generations, evolving toward 3GPP-defined signaling and Diameter in newer architectures.

Security and reliability are central concerns, as signaling infrastructures are targets for abuse and disruption. Measures include encryption, strong authentication, network segmentation, and robust signaling protocols. Standards are coordinated by ITU-T, IETF, 3GPP, and ETSI, guiding interoperability and evolution toward cloud-native, IP-based signaling in next-generation networks.