Overview
ISO/IEC 29341-18-12:2011 specifies the RADASync service - the Remote Access Discovery Agent Synchronization Service - as part of the UPnP Device Architecture (Part 18-12 of the ISO/IEC 29341 family). The standard defines a UPnP service type that enables an in-band synchronization mechanism between Remote Access Clients and Remote Access Servers (Remote Access Discovery Agents, or RADAs). Its goal is to provide an aggregated, up-to-date view of UPnP devices and services across local and remote networks while reducing chatty SSDP traffic and alleviating timing/deadline dependencies inherent in UPnP discovery.
Key Topics and Requirements
- Service compliance: RADASync is compliant with UPnP Device Architecture v1.0 and follows UPnP service modeling, eventing and XML service description conventions.
- Primary functions:
- Publish and remove information about remote UPnP devices and services.
- Notify control points of peer RADA availability.
- Allow registration of RADASync co‑located with a control point.
- Synchronization model: Aggregates local SSDP monitoring with synchronized device lists from remote RADAs to maintain a consolidated device/service view.
- Actions & state variables (defined at a service level): Examples in the standard include AddRemoteDevices(), RemoveRemoteDevices(), SetDDDLocation(), HeartbeatUpdate(), plus state variables such as SystemInfo and DeviceInfoList. Error codes, eventing moderation and XML schemas are specified.
- Operational requirements: Initialization, synchronization behavior, SSDP offloading considerations, heartbeat mechanisms, administrative shutdown handling, and IPv6 signalling to remote networks are addressed.
- Scope exclusions: The standard explicitly does not define the transport protocol for remote access, local aggregation mechanisms, local relaying of SSDP on behalf of remote devices, or policies for visibility configuration between local and remote devices.
Practical Applications and Who Uses It
- Device and firmware manufacturers implementing UPnP-enabled routers, NAS devices, gateways and IoT hubs can use RADASync to improve remote discovery and reduce cross-network SSDP chatter.
- Control point developers and UPnP software stacks implementers use the service to provide reliable discovery results in remote scenarios.
- Network architects and system integrators designing remote access solutions use the standard to specify discovery synchronization, heartbeat and administrative behaviors across distributed networks.
- Remote access service providers can adopt RADASync to deliver consistent remote device visibility and to mitigate timing and bandwidth issues in constrained links.
Related Standards and References
- UPnP Device Architecture v1.0 (normative dependency)
- RADiscoveryAgent device specification and associated XML schema (DADS-XSD)
- RFC 2119 (requirements keywords)
- ISO/IEC 29341 series (UPnP device architecture family)
Keywords: ISO/IEC 29341-18-12:2011, RADASync, Remote Access Discovery Agent, RADA, UPnP, SSDP, remote device discovery, UPnP Device Architecture, Remote Access Device Control Protocol.