RAN Simulator
The RAN Simulator lets you exercise a live core network without physical radios or handsets. It stands up virtual eNodeBs and UEs that speak real S1AP/NAS to the MME and GTP-U to the gateways, so you can drive attaches, data sessions, IMS registrations, SMS and calls — for functional testing, load testing, or reproducing field scenarios — all from OmniWeb.
What It Is
The simulator runs alongside the core it targets. In OmniWeb it appears as its own RAN Simulator area (Network Map, eNodeBs, UEs, IMS, Load Test), and — because a simulated UE behaves like a device — its UEs also appear in Test Devices so you can drive them from the same place as real handsets.
By default it starts with no eNodeBs — you turn up exactly the topology you want.
eNodeBs
Turning up an eNodeB attaches it to the MME (S1 Setup). An eNB can be connected to more than one MME (an MME pool) — the Network Map shows the full set of MMEs an eNB is homed to.
Turn-up is fire-and-forget: OmniWeb asks the simulator to bring the eNB up and returns; the S1 link establishes in the background (watch the Network Map / eNodeBs list to confirm it came up).
Disconnecting an eNodeB
You can take an eNB down two ways, which model different real-world events:
| Action | Models | Effect on UEs |
|---|---|---|
| Clean S1 disconnect | An orderly eNB shutdown / S1 reset | UEs are released cleanly and survive — they re-attach when a link is available |
| Drop link | The eNB abruptly losing its S1 (fibre cut, power loss) | The S1 association is aborted; UEs survive the eNB going away and re-attach rather than being torn down |
Critically, taking an eNB down does not destroy its UEs — the UEs persist and re-attach, so you can simulate transport outages without rebuilding your fleet of subscribers.
UEs
Each simulated UE has a lifecycle you can drive directly:
- Attach / Detach — join or leave the network.
- Send to idle — move to ECM-IDLE (as a real UE does between activity); paging or new activity brings it back.
- Out of coverage — an unclean loss of radio (the UE drops without signalling), to test how the core handles a UE that simply vanishes. Attaching brings it back into coverage.
For each UE the simulator shows the serving MME it is attached to — the MME Group ID and MME Code (decoded from the UE's GUTI) — so in a pooled deployment you can see which MME picked up each subscriber.
IMS registration & location
A simulated UE can register to IMS and place SMS/calls. When it registers, it includes its cell location (P-Access-Network-Info with the utran-cell-id-3gpp for its serving cell), exactly as a real UE does — so the S-CSCF's third-party REGISTER propagates that location to the SMSc, TAS, and other application servers. This lets you test location-dependent IMS behaviour end to end without real radios.
Driving UEs from Devices
Because a simulated UE is just another device, it shows up in Test Devices tagged as a simulator, and can be filtered to there. The same UE control panel is used whether you open a UE from the RAN Simulator's Network Map or from the Devices fleet — one place to attach/detach, idle, drive out-of-coverage, register to IMS, send an SMS or place a call, and watch the action log.
Filter Test Devices to the RAN Simulator UEs to drive emulated subscribers alongside real handsets.
Typical Uses
- Functional testing — turn up an eNB and a UE, attach, bring up a data session, register to IMS, send an SMS — confirm each core element behaves.
- Load testing — bring up many UEs to generate attach/session/IMS load against the core (see the Load Test view).
- Scenario reproduction — model outages (drop link, out of coverage) and pooled-MME behaviour to reproduce and diagnose field issues.
Related
- Test Devices — real handsets and simulated UEs, driven from one place.
- Session Trace — correlate the signalling the simulator generates.