State-Owned Enterprise Group Office IP Telephony System

Customer Requirements

• IP communications must serve every office floor and be easy to expand.
• A high-availability design to guarantee system stability.
• Enterprise-grade security, including firewall policies.
• Voice traffic must be isolated from office data networks.
• Dual IMS trunks from China Unicom with redundancy.
• Zero additional cabling.
• Stand-alone fax machines on each floor.
• Corporate main number (auto-attendant).
• Internal short-number dialing; all outbound calls via Unicom IMS.
• Features: caller ID, CDR, call transfer/forward, conferencing, DND, IVR, fax, etc.
• Call-recording service.
• Future-proof expansion and low-cost maintenance; control total cost of ownership.
• Stable, efficient, convenient, and accurate call services.

Solution

Deployment Details

• Core VLAN switch separates voice and data networks.
• IP-PBX, media gateways, and SBC reside in the main data center; IP-PBX is deployed in active-standby HA mode.
• SBC3000 links to China Unicom IMS via dual IMS trunks for redundancy; it also isolates internal/external networks, hides topology, and prevents attacks.
• 1,000 Telling IP phones pre-installed (one per desk); phones and PCs receive dynamic IPs from separate VLANs.
• Centralized phone-management system for zero-touch provisioning and remote configuration—no extra cabling required.
• One 4-port analog gateway per floor connects to fax machines.
• Internal extensions support short-dial, transfer, conference, 3-way call, barge-in, break-in, call forward, etc.
• All employees use Unicom IMS for outbound calls; corporate main-number service provided.
• IP-PBX offers call-recording for all extensions with CDR and recording reports.
• Highly scalable architecture for future growth.
• Centralized phone-management platform for remote maintenance and efficient operations.

Solution Highlights

• Ultra-large IPPBX: Supports 1,000–12,000 users out of the box and scales effortlessly.
• All-IP Deployment: No desk wiring for phones; distributed IP architecture lowers deployment and maintenance costs while speeding installation.
• High Reliability: Core IPPBX in active-standby HA, dual load-balanced media servers, plus dual IMS trunks for redundancy—maximizing uptime.
• Network Security: Complete VLAN separation between voice and data networks; SBC secures China Unicom IMS trunks with topology hiding, anti-attack, and inside/outside network isolation.
• Converged Services: Corporate main number, short-dial between extensions, call transfer/forward, IVR navigation, fax, recording, voicemail, and more.
• Multi-party Conferencing: Free, in-house audio conference platform—mobiles, desk phones, or extensions can join; multiple independent conference rooms run simultaneously with stable quality. Role-based entry (admin vs. user) boosts confidentiality. Rich chair controls: mute all, unmute all, invite, mute individual, remove participant, etc.
• Intelligent Voice Reception: Smart IVR auto-answers, guides callers through dial-by-name/department options, connects them to the right person faster, and improves inbound experience.
• Automated Deployment: NMS network-management system centrally manages IP phones, voice gateways, and SBCs—bulk provisioning, mass firmware upgrades, configuration backup, and remote maintenance—cutting OPEX and boosting efficiency.