Description
Growing businesses need a communications system that supports both modern tools and existing infrastructure without unnecessary complexity or recurring fees. The Grandstream UCM6302 IP PBX delivers exactly that — a complete unified communications platform with support for up to 1,000 users and 150 concurrent calls. It includes 2 FXS ports for analog phones and 2 FXO ports for PSTN lines, both with automatic lifeline capability during power outages.
Built-in voice and video conferencing, the free Wave app for desktop, mobile, and web, plus robust security features make it simple for teams to stay connected whether they are in the office or working remotely. Zero-configuration provisioning for Grandstream endpoints and compatibility with the free GDMS cloud platform allow IT teams and business owners to deploy and manage the system quickly and confidently.
The Telecom Spot Take
For small and medium-sized businesses that want enterprise-grade unified communications scaled to their actual needs, the UCM6302 offers an outstanding balance of capacity, features, and value. The 2 FXS + 2 FXO configuration provides practical flexibility for offices that still rely on some analog phones or traditional phone lines while giving them a clear path to full VoIP.
With room for 1,000 users and strong concurrent call handling, it supports growing teams and hybrid work without forcing customers to purchase oversized systems. The built-in meeting platform and Wave app reduce or eliminate the need for separate video conferencing subscriptions, while automated NAT traversal and strong security features (secure boot, unique certificate, random default password) simplify secure remote access — something many of our customers now consider essential. This is a smart, future-ready choice for organizations that value reliability, ease of management, and cost control.
Key Features
- 2 FXS + 2 FXO RJ11 ports with lifeline capability — Connect analog phones and traditional PSTN lines while maintaining service automatically during power outages, giving businesses continuity and a smooth transition path to VoIP.
- Support for up to 1,000 users and 150 concurrent calls (G.711) — Handles the full communication load of small to mid-sized teams with headroom for growth; up to 100 concurrent SRTP calls for encrypted conversations.
- Built-in conferencing and meetings platform — Host voice and video meetings directly on the PBX with support for up to 8 simultaneous public rooms, 150 total participants across rooms, and up to 9 video feeds per room — no extra licensing or third-party services required.
- Free Wave app for Android, iOS, Windows, Mac, Chrome, and Firefox — Enable remote and mobile workers to make/receive calls, join meetings, and collaborate with the entire system from anywhere using a single, easy-to-use application.
- Advanced security protections — Includes secure boot, unique security certificate, random default password, SRTP/TLS encryption, and more to safeguard calls, accounts, and data right out of the box.
- Three self-adaptive Gigabit Ethernet ports with PoE+ and NAT router support — Flexible network deployment with Power over Ethernet for connected devices and built-in routing to simplify infrastructure.
- Automated NAT firewall traversal (UCM RemoteConnect) — Simplify secure remote connections for off-site users and devices without complex manual VPN setups.
- Zero-configuration provisioning for Grandstream SIP endpoints + GDMS compatibility — Rapidly deploy phones and manage the entire system locally or through the free cloud-based Grandstream Device Management System for monitoring, firmware updates, and troubleshooting.
- Comprehensive voice and video codec support with high jitter resilience — Full-Band Opus, G.711, G.722, G.729 and other voice codecs plus H.265/H.264/H.263/VP8 video codecs deliver clear quality even on challenging networks (up to 50% packet loss resilience).
- Extensive built-in call features — Includes call queues, IVR (up to 64 layers), voicemail-to-email, fax-to-email, ring groups, call recording, paging/intercom, time-based routing, and many more tools to improve efficiency and customer experience.
Technical Specifications
Interfaces
| Analog Telephone (FXS) Ports | 2 × RJ11 (lifeline capable, expandable via gateway) |
| PSTN Trunk (FXO) Ports | 2 × RJ11 (lifeline capable, expandable via gateway) |
| Network Interfaces | 3 × self-adaptive Gigabit RJ45 ports (switched, routed, or dual mode) with integrated PoE+ |
| Peripheral Ports | 1 × USB 2.0, 1 × USB 3.0, 1 × SD card slot |
| Display & Controls | 128×32 dot matrix graphic LCD with navigation buttons, reset switch, dual DC 12V power inputs |
Capacity
| Maximum Users | 1,000 |
| Maximum Concurrent Calls (G.711) | 150 |
| Maximum Concurrent SRTP Calls (G.711) | 100 |
| Meeting Capacity | Unlimited meeting rooms (up to 8 simultaneous public rooms); max 150 simultaneous participants across all rooms; up to 9 video feeds per room |
Voice & Video Codecs
- Voice/Fax: Opus (Full-Band), G.711 A-law/U-law, G.722, G.722.1/G.722.1C, G.723.1, G.726-32, G.729A/B, iLBC, GSM; T.38 fax
- Video: H.265, H.264, H.263, H.263+, VP8
- Voice-over-Packet: LEC with NLP, 128 ms tail-length carrier-grade echo cancellation, dynamic jitter buffer, NetEQ, FEC 2.0
Security
- Media & Signaling: SRTP, TLS, HTTPS, SSH, 802.1X, ZRTP
- Advanced: Secure boot, unique security certificate, random default password
Management & Provisioning
- Web-based administration interface
- ZeroConfig auto-provisioning for Grandstream endpoints (DHCP Option 66, multicast, mDNS)
- Full API for third-party integrations (CRM, PMS, etc.)
- Compatible with free GDMS cloud platform for centralized provisioning, monitoring, and management
- Multi-language support for web UI and customizable IVR/voice prompts
Physical & Environmental
| Dimensions | 485 mm (L) × 187.2 mm (W) × 46.2 mm (H) |
| Weight | 725 g (unit) |
| Mounting | Rack-mount and desktop |
| Power | Dual DC 12V inputs (universal power adapter) |
| Operating Temperature | 0–45 °C (32–113 °F), 10–90% non-condensing humidity |
| LED Indicators | Power, FXS, FXO, LAN, WAN, Heartbeat |
Network & QoS
- Protocols: SIP, TCP/UDP/IP, RTP/RTCP, IAX, ICMP, ARP, DNS, DDNS, DHCP, NTP, TFTP, SSH, HTTP/HTTPS, PPPoE, STUN, SRTP, TLS, LDAP, IPv6, OpenVPN, and more
- QoS: Layer 2 (802.1Q/p) and Layer 3 (ToS, DiffServ, MPLS)
- DTMF Methods: In-band, RFC2833, SIP INFO
Model Comparison (UCM6300 Series)
| Model | FXS / FXO Ports | Max Users | Max Concurrent Calls (G.711) | Best For |
|---|---|---|---|---|
| UCM6301 | 1 / 1 | 500 | 75 | Very small offices or single-site with minimal analog needs |
| UCM6302 | 2 / 2 | 1,000 | 150 | Small to medium businesses needing balanced analog + VoIP and growth headroom |
| UCM6304 | 4 / 4 | 2,000 | 300 | Larger offices or multi-site with more analog infrastructure |
| UCM6308 | 8 / 8 | 3,000 | 450 | Larger enterprises or organizations with heavy analog/PSTN requirements |
Frequently Asked Questions
How many users and concurrent calls does the UCM6302 support?
It supports up to 1,000 users and 150 concurrent calls (G.711), with up to 100 concurrent SRTP encrypted calls.
Can I keep using my existing analog phones and PSTN lines?
Yes. The UCM6302 includes 2 FXS ports for analog telephones and 2 FXO ports for PSTN trunks. Every port has lifeline capability so service continues automatically if power is lost.
Does the UCM6302 support video conferencing and remote workers?
Yes. It has a built-in voice and video conferencing platform plus the free Wave app (Android, iOS, desktop, and web) that lets remote users make/receive calls and join meetings from anywhere. Automated NAT traversal makes secure remote access straightforward.
What security features are included?
The system includes secure boot, a unique security certificate, random default password, SRTP/TLS encryption, and additional protections to safeguard communications and accounts from the moment it is powered on.
How easy is setup and ongoing management?
Very straightforward. It supports zero-configuration provisioning for Grandstream phones, a full web interface, and the free GDMS cloud platform for centralized management, monitoring, and firmware updates. A comprehensive API is also available for custom integrations.
Is there a mobile or desktop app for end users?
Yes — the free Wave app works on Android, iOS, Windows, Mac, Chrome, and Firefox browsers, giving users a consistent experience for calls and meetings whether they are in the office or remote.


