# OpenScape 4000 STMIX — HG 3500 Common Gateway Card

URL: https://www.promark.tr/en/products/stmix
Category: Expansion Cards & Modules
Family: [OpenScape 4000 Cards](https://www.promark.tr/en/products/openscape-4000-cards)

Common Gateway HG 3500 card that adds 120-channel SIP/IP trunk capacity to OpenScape 4000 — designed to migrate operator connectivity from TDM to IP, with hot-plug support.

## Key features

- Subscriber Trunk Module IP eXtended (STMIX) — serves as OpenScape 4000's HG 3500 Common Gateway.
- Two 1 Gbps Ethernet network connections — redundant IP backbone or separate VLANs for QoS isolation.
- 120 channels with the PDMX (PMC DSP Module Extended) module — sufficient capacity per card for heavy traffic.
- x86 CPU-based voice encoding — software-driven, flexible codec management.
- Hot-pluggable — can be inserted/removed while the system runs, no outage at commissioning.
- Installs in a standard peripheral slot of the AP3700 host shelf — works via backplane with the default peripheral board.
- USB type-B service interface — local access for diagnostics and tests.
- Active/standby HG 3500 configuration supported (from V8R1) — high-availability trunk connectivity.
- Successor of the STMI2 card — mandatory upgrade for installations where STMI2 support ended at V10R0.

## Specifications

- **Type:** Subscriber Trunk Module IP eXtended (STMIX)
- **Role:** HG 3500 Common Gateway
- **Shelf:** AP3700 host shelf, standard peripheral slot
- **Trunk type:** SIP / IP (TDM ⇄ IP)
- **Channels:** 120 (with PDMX module)
- **Network:** 2× 1 Gbps Ethernet
- **Service interface:** USB type-B (test)
- **Voice encoding:** x86 CPU-based
- **Hot-plug:** Yes
- **Redundancy:** Standby HG 3500 (V8R1+)
- **Max parallel boards:** 4 (per LUNA2 PSU)
- **Supported codecs:** G.711, G.729
- **Codec restrictions:** G.722, G.723 and OPUS not supported
- **Module:** PDMX (PMC DSP Module Extended) — S30810-Q2343-X
- **Successor:** STMIY (newer generation)
- **Predecessor:** STMI2 (discontinued at V10R0)

## Use cases

- Migrate TDM operator lines to SIP trunk — phased migration, continuous operation, 120 channels per card.
- Add IP trunk capacity to an existing OpenScape 4000 — preserves AP3700 shelf occupancy.
- Standby HG 3500 configuration — two STMIX cards for high-availability operator connectivity.
- STMI2 → STMIX hardware refresh — mandatory on V10R0+ systems where STMI2 support has ended.

## For a quote and BOM

https://www.promark.tr/en/contact · +90 312 544 0915 · destek@promark.tr