Inbound GSM & IVR

Handle mobile calls that ring a VMGateClient SIM — play an IVR, forward to a Customer switch, or reject — when the handset is set to forward incoming GSM to the server.

What inbound GSM is

Outbound termination (chapters 09–10) is Customer SIP → VMGateServer → GSM. Inbound GSM is the reverse path for calls that arrive on the phone’s SIM:

Mobile caller → GSM SIM on VMGateClient → VMGateServer → IVR and/or Customer SIP switch

Use inbound when you want callers who dial the SIM number to hear menus, leave a path through your IVR graph, or be connected to a Customer destination — without answering the call only on the phone screen.

Two layers (handset + portal)

Inbound needs both layers configured correctly:

1. On the phone (Layer 1) — menu → Settings → Incoming GSM calls → choose Forward to server. Other choices (Answer locally, reject-all, local prepared clips) stay on the handset and do not use portal IVR / Forward dialpeers. See the VMGateClient manual.
2. In the portal (Layer 2) — per SIM slot (or network defaults) set what the server does after the handset forwards: IVR, Forward, or Reject (chapter 05).

If the handset is not on Forward to server, portal Layer-2 settings are unused for that call. If Layer-2 is Reject (the safe default when nothing was configured), the server declines the inbound attempt even when the handset forwards.

Slot and network mode (Layer 2)

Open Management → VMGateClients → client Details → Edit policy on a SIM slot (or Networks → ⋮ → Edit defaults for new enrollments). Under Inbound GSM (when handset forwards to server):

• IVR — pick an active IVR profile (required). The caller hears that IVR after the GSM leg is answered by the server path.
• Forward — pick an active inbound dialpeer (required). The call is forwarded toward a Customer switch using that dialpeer’s routing rule and trunk. Optional called-number fallback fields apply only in this mode.
• Reject — decline. No IVR or dialpeer required. Unset / never configured behaves as Reject.

Network defaults copy to a slot only when a client first joins. Changing defaults later does not rewrite existing devices — edit each slot or use bulk voice policy carefully.

Inbound trunks, rules, and dialpeers

Open the sidebar group Inbound GSM (separate from outbound Customers / Routing / Dialpeers):

• Trunks — SIP destinations for forward (host, port, transport, mandatory tech prefix, concurrent caps). Tech prefix is prepended when dialing the destination number.
• Routing rules — match called prefixes (longest wins). Optional overrides for IVR, trunk, called userpart, and From / CLI mode.
• Dialpeers — named bind from slot/network Forward mode to a routing rule. This is what you select on the slot when mode is Forward.

Use the ⋮ menu on each row for edit / activate actions. Do not confuse these with outbound Configuration → Trunks / Routing rules / Dialpeers (chapters 06, 09, 10).

IVR profiles

Open Inbound GSM → IVR (or the IVR workspace from Management). Create profiles with a name and optional prefix. Each profile has ordered steps:

• Upload an audio file, then Prepare so VMGateServer converts it for the phone path. Status must be ready before live use.
• Ask for key — when on, after the step prompt the system waits for a digit; silence can replay the step when collect is enabled.
• Initial silence (profile setting) — short silence before the first prompt when needed for media warmup.
• Actions (per step) — map keys 0–9, *, # to what happens next (see below).
• Preview — open the block scheme, play a step, and press keypad keys to walk the graph without a live GSM call. Forward in Preview stays on the step (does not place a real forward).
• Export — download IVR journey results as CSV for a date range.

Digit Actions

On a step, open Actions. For each key choose one action:

• Play file — upload + prepare audio in the File column; after play, the same step resumes (does not hang up by itself).
• Play IVR — jump to another IVR profile.
• Back one level / Main IVR / End call — navigation and hangup.
• Forward to dialpeer — mid-IVR transfer toward a Customer switch.

Forward to dialpeer — settings (⚙)

Keep the dialpeer on the Actions row. When a dialpeer is selected, the ⚙ icon unlocks. Click it to open Forward settings (the overlay does not open by itself):

• Number to dial — digits only; always dialed for this Action. Trunk tech prefix is prepended automatically — do not type the tech prefix here.
• Min ring / Max ring (seconds) — random hold between min and max (0–30, min ≤ max) before the outbound INVITE. 0 / 0 with no comfort file means dial immediately.
• Comfort music (optional) — upload + prepare like a play-file prompt. Played during the hold and kept until the far end answers, then media connects.

Why two phases: some destinations answer almost immediately; others ring for a long time. VMGateServer always applies the min–max hold first (no dial yet), then dials and keeps comfort until answer — so the GSM caller does not hear a clipped ring or music overlapping the far-end audio.

Save Forward settings with Save on the overlay, then Save on the Actions dialog. Re-open Actions after deploy or policy changes and confirm number + ring fields.

Related outbound chapters

Inbound catalog objects are under Inbound GSM. Outbound Customer trunks and dialpeers remain chapters 06, 09, and 10. Slot caps, idle, and dial policy for outbound termination remain chapter 05.

Related app chapters

• Calls & audio — Layer-1 Incoming GSM settings.
• Daily use — SIM card states while inbound rings or talks.
• Troubleshooting — handset forward / audio checklist.