Guide · SIP integration
PBX integration with intercom & access control via SIP
A detailed guide: how to open any door, gate or barrier from IP phone, mobile or softphone. Protocols SIP, DTMF, RTSP, HTTP. Real scenarios and code.
Why integrate PBX with ACS
A standalone intercom panel and a standalone ACS create two independent control circuits. Security staff must watch both. PBX integration turns any phone — IP phone in the office, mobile on duty, softphone on laptop — into a universal access control panel. No separate workstation with monitor and mouse, no staff training. Any employee with a phone can open a door, see the visitor on video, check the whitelist and get an event in the journal.
Use cases
Six typical scenarios we deliver regularly. All run on iPECS UCP + 2N/Beward/Sigur/Parsec. Real cases — offices for 50–500 people, warehouses, villas, server rooms.
| Scenario | What happens | Hardware |
|---|---|---|
| Office, visitor | Guest presses intercom button → SIP call to reception → answer → DTMF 9 → door opened | 2N IP Verso, iPECS |
| Warehouse, gates | Driver dials mobile → SIP call to warehouse → manager sees number → DTMF 5 → barrier opened | 2N Access Unit, Beward |
| Home, guest at door | Doorbell → push to iPECS UCS on phone → camera video in app → open button | 2N Indoor Touch, iPECS UCS |
| Server room, access | Card → log to 1C → SIP call with code to security → on confirmation — door opened. No card = no entry | Sigur + SIP gateway, 1C |
| Parking, time-based | 9:00–18:00 — whitelist call → open. 18:00–9:00 — busy or divert to security | iPECS time routing + 2N |
| Alarm | ACS/security signal → SIP call to security group → on confirm — disable. All events logged | Bolid / Sigur + gateway |
Protocols
A stack of 6 protocols is used for integration. Each for its own task. SIP — the foundation, without it no call. DTMF — for in-call commands. RTSP — for video. HTTP API — for programmatic control without a call. Wiegand — for wired card reader connection. MQTT — for IoT events.
| Protocol | Purpose | Where used |
|---|---|---|
| SIP | Call signaling (invite, answer, hangup) | 2N, Beward, Sigur, Parsec |
| DTMF (RFC 2833) | Tones in-band for commands | Open by pressing 9 |
| RTSP | Streaming video from intercom camera | Softphone / video phone |
| HTTP API | Programmatic control — POST to URL | Sigur, Parsec, Bolid |
| Wiegand | Wired card reader protocol | IronLogic |
| MQTT | Lightweight IoT events | Sigur, Beward |
Analog intercoms
If the building has analog intercoms (Cyfral, Vizit, Eltis, Metakom), you don't have to replace the panel. Connect via SIP gateway. SL-30 and Grandstream HT801 with mixer are popular solutions. On the PBX side, the gateway registers as a regular SIP extension, receives a call when the panel button is pressed, transmits audio, accepts DTMF.
DTMF — open by digit
The simplest way to open a door from a phone is to press 9 (or any other digit) during the intercom call. The phone sends a DTMF tone via SIP — the entrance panel or controller recognizes it and triggers the lock relay. On the PBX side — standard IVR script: "answer, wait 1s, send 9, hang up". Or more complex: request PIN, check against whitelist, open.
; Incoming call from intercom EXT 200
; Answer, wait for pickup, send DTMF
; press 9 to open the door
[from-sip-200]
exten => 200,1,Answer()
exten => 200,n,Wait(1)
exten => 200,n,SendDTMF(9)
exten => 200,n,Wait(2)
exten => 200,n,Hangup()
; Scenario: DTMF 1 from extension -> open door
[macro-open-door]
exten => s,1,Read(dtmf,,1)
exten => s,n,GotoIf($["${dtmf}"="9"]?open:reject)
exten => s,n(open),System(/usr/local/bin/open-door.sh)
exten => s,n,Playback(opened)
exten => s,n,Hangup()
exten => s,n(reject),Playback(forbidden)
exten => s,n,Hangup()
Video in softphone
Seeing the visitor before opening is mandatory for offices, warehouses, server rooms. IP cameras and IP intercoms support RTSP streams, picked up by softphones (iPECS UCS Premium, MicroSIP, Phoner) and video phones (iPECS LIP-9071, 2N Indoor Touch). On incoming intercom call — camera video auto-shows in the call window. One "Open" button — call ends, door opens, event logged.
- iPECS UCS Premium on smartphone: intercom video on incoming call, "Open" button right in the call window
- iPECS LIP-9071 video phone: intercom video in real-time on a 7" screen
- 2N Indoor Touch: dedicated video answering unit on the desk, always shows the entrance panel
- RTSP stream from any IP camera or intercom to iPECS Video Client — for security staff
Security
The main risk of SIP-based opening — the caller may not be who they claim (Caller ID spoofing). Protection — whitelist of numbers (only 495-XXX-XX-XX can open), PIN before open (4 digits via IVR, logged in CDR), journal of all events (who, when, from what number, which door), Telegram/email notification to security on every open. On iPECS UCP all this is configured through web UI in 30 minutes.
Compatible hardware
We support SIP intercoms and ACS controllers from 2N, Beward, TrueIP, Hikvision, Dahua, Sigur, Parsec, Bolid, IronLogic, Sphinx, PERCo, Gate. If your brand isn't in the list — send the model and we'll verify compatibility within 1 business day.