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OmniDRA

OmniDRA is a Diameter Routing Agent. It relays Diameter signalling between clients (MME/SGSN, PCEF, AS) and services (HSS, PCRF, OCS). It supports interfaces such as S6a, Gx, Gy, Cx and Sh. On top of standard RFC 6733 relay routing, it adds content-based routing, AVP transformation, security screening, roaming control and analytics.

What it does​

  • Routes Diameter traffic by Destination-Host and Destination-Realm, with peer selection and failover.
  • Content-based routing - direct or drop traffic using rules that match on application, command, realm, IMSI and the peer a message arrived from.
  • AVP transformation - rewrite realms and other AVPs on matching messages for MVNO, roaming and migration scenarios.
  • Security screening - GSMA FS.19/FS.21 aligned firewall, topology hiding, per-peer rate limiting and AVP sanitisation.
  • Roaming steering & subscriber lookup - steer roamers to preferred networks and route location requests to the correct serving node.
  • Metrics - Prometheus metrics for peer health, traffic and module activity.

Documentation​

The operations guide is split into focused pages. Start with the Architecture Overview, then move to the topic you need.

Operations Guide​

  • Architecture Overview - What the DRA is, where it sits in a Diameter network, and how a request flows through the processing pipeline.
  • Base Configuration - The core diameter configuration block: service identity, network settings, peer admission, and the peer list.
  • SCTP Multihoming - Configuring multi-homed SCTP associations across multiple local and peer IP addresses for transport resilience.
  • Standard Diameter Routing - Destination-Host / Destination-Realm routing precedence, the global peer selection algorithm, and unroutable-message handling.
  • Advanced Routing - Content-based rules with per-rule failover, priority/weight load balancing, and Destination-Host session affinity for Gx/Gy.
  • Advanced Transform - Rewriting AVPs in matching Diameter messages.
  • Metrics & Monitoring - Prometheus metrics, labels, and example PromQL queries.
  • Troubleshooting - Symptoms, causes and resolutions for common operational issues.

Feature Modules & Reference​

  • Diameter Security - GSMA FS.19/FS.21 compliant security modules: Diameter Firewall, Topology Hiding, Rate Limiter, AVP Sanitizer.
  • Roaming Steering (SoR) - Steer roaming subscribers to preferred VPLMNs by rejecting Update-Location-Requests from non-preferred networks.
  • Subscriber Lookup (SLF) - Dynamically learns subscriber-to-serving-node bindings from Diameter traffic and routes SLg/SLh requests to the correct serving node.
  • Peer Connectivity & Settle Time - Tunable come-up delay that keeps traffic off flapping peers until they are ready to carry it.