Quais são as tendências e normas emergentes para a sinalização em redes NGN?

Emerging trends and standards for signaling in Next-Generation Railway Networks include adopting service-based architecture for modular and flexible network functions, integrating advanced technologies like 5G for improved communication, emphasizing cloud-native solutions for agility, and using edge computing to reduce latency and enhance performance.

Session Initiation Protocol (SIP) is a widely used signaling protocol that allows for the initiation, maintenance, and termination of real-time communication sessions, including voice, video, and messaging. In the context of railway signalling, SIP can facilitate seamless voice communications between train operators and control centers, which is essential for operational coordination. This protocol supports the dynamic nature of railway operations, where quick and reliable communication is crucial.

Diameter is an advanced protocol that builds upon the foundation laid by RADIUS, providing a more robust framework for authentication, authorization, and accounting (AAA). In railway signalling systems, Diameter is particularly valuable because it can handle complex AAA requirements, ensuring secure access to signalling and control systems. RADIUS, while still relevant, is limited compared to Diameter, particularly in handling modern AAA needs that arise from the increasing complexity of network services. In railway applications, Diameter can support user session management and billing for services like ticketing and passenger information systems. This capability not only enhances security but also streamlines operations.

H.323 is an ITU-T standard designed for audio, video, and data communications across packet-based networks. In railway signalling, H.323 can facilitate video conferencing between control centers and field operators, which is essential for real-time decision-making and response. This can significantly improve communication during emergencies . On the other hand, Megaco (H.248) is a protocol specifically used for controlling multimedia gateways. By employing Megaco, railway signalling systems can manage the interaction between traditional phone networks and IP-based systems. This ensures that operators can leverage both types of communication seamlessly, allowing for greater flexibility and reliability in managing railway operations.

SIGTRAN is a suite of protocols designed to transport signaling messages over IP networks, primarily utilizing Stream Control Transmission Protocol . This integration is particularly beneficial for railway signalling, as it allows traditional signaling systems to operate over modern IP networks, ensuring robust and reliable message delivery. SCTP, as a transport protocol, offers unique features like multihoming and message-oriented transport. In the context of railway signalling, these features are advantageous for ensuring redundancy and fault tolerance. For example, if one communication path fails, SCTP can reroute the messages through another path, maintaining continuous operation and enhancing the reliability of train control systems.

WebRTC enables real-time peer-to-peer communication between web browsers, which is highly beneficial for railway signalling. It allows immediate audio and video communication between train crews and control centers, enhancing situational awareness and response times during critical situations. WebSocket complements this by providing a low-latency, full-duplex communication channel over a single TCP connection. In railway applications, it facilitates real-time data streaming for monitoring train status and operational updates. Together, WebRTC and WebSocket improve operational efficiency, enabling quick information sharing and informed decision-making.