Connectivity Service

Enterprise SIP Trunking With Carrier-Grade Reliability

Replace costly legacy ISDN circuits with elastic SIP channels that scale instantly with your call volume — backed by redundant infrastructure, automatic failover, and carrier-grade quality at a fraction of the cost.

Unlimited
Channel Scaling
99.9%
Uptime SLA
50%+
Cost Savings vs ISDN
24/7
Support

Tech Network Limited's SIP trunking service connects your existing PBX, UCaaS platform, or softswitch directly to our carrier-grade voice network. Unlike traditional ISDN circuits, SIP trunks scale elastically — adding and releasing channels in real time to match your actual call volume, eliminating the cost of over-provisioning.

Our trunks are delivered over dual-carrier, redundant connections with automatic failover between network paths. If your primary connection experiences any degradation, traffic routes to a secondary path within seconds — maintaining service continuity without manual intervention.

  • Elastic channels — scale from 1 to 10,000+ without hardware
  • Redundant dual-carrier delivery with automatic failover
  • Supports all major PBX systems (Cisco, Avaya, 3CX, Asterisk)
  • G.711, G.729, G.722, and Opus codec support
  • Competitive per-minute and flat-rate monthly pricing

Elastic Scaling

Channels scale automatically with demand — handle peak call volumes without pre-provisioning capacity you don't use day-to-day.

Built-In Redundancy

Dual-path delivery with automatic failover between network routes. Your calls continue uninterrupted even during carrier disruptions.

Cost Savings

Customers typically save 40–60% versus legacy ISDN/PSTN circuits, with no per-channel hardware costs and usage-based billing options.

Universal Compatibility

Works with any SIP-compatible PBX, UCaaS platform, or softswitch — Cisco, Avaya, 3CX, Asterisk, FreePBX, and more.

What's Included

Enterprise SIP Trunking, Built for Scale

Elastic Channel Capacity

Start with as few channels as you need and scale instantly to thousands — no hardware provisioning, no lead time, no minimum channel commitment.

Redundant Dual Paths

All trunks are delivered over geographically diverse network paths with automatic failover — eliminating single points of failure.

SIP Registration & IP Auth

Supports both IP-based authentication (for static IP deployments) and SIP registration (for dynamic IP or remote workers).

Codec Flexibility

Full support for G.711 a-law and u-law, G.729 (bandwidth-efficient), G.722 (HD voice), and Opus — negotiated automatically during call setup.

Real-Time Usage Monitoring

Live channel utilisation dashboard showing active calls, peak usage, CDR access, and quality metrics — all in your online portal.

Flexible Billing Options

Choose from per-minute billing for variable traffic, flat-rate monthly bundles for predictable costs, or a hybrid of both.

Technical Specifications

Protocol SIP (RFC 3261), SIP over TLS/SRTP (optional)
Channel Capacity 1 to 10,000+ concurrent channels
Authentication IP whitelist or SIP registration
Codecs G.711 (a/u), G.729, G.722, Opus
Redundancy Dual carrier paths, automatic failover
DTMF RFC 2833, SIP INFO, in-band
Uptime SLA 99.9%
Billing Per-minute, flat-rate monthly, or hybrid
Setup Time Same-day for standard configurations

Compatible With

  • Cisco CUCM, Cisco UCM Cloud
  • Avaya IP Office / Aura
  • 3CX Phone System
  • Asterisk / FreePBX / FusionPBX
  • Microsoft Teams Direct Routing
  • FlexSwitch (native integration)
  • Any RFC 3261 SIP-compliant PBX

Microsoft Teams Direct Routing certification available. Encryption (SIP TLS + SRTP) and SBC (Session Border Controller) integration support available on request.

Use Cases

Who Uses SIP Trunking

🏚

Enterprise PBX Migration

Migrate from legacy ISDN trunks to SIP at a fraction of the cost — without replacing your existing PBX investment.

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Multi-Site Businesses

Connect multiple office locations through a centralised SIP trunk configuration, with shared channel pools and unified dial plans.

UCaaS & Cloud PBX Providers

Platform operators use our SIP trunking to deliver outbound calling and DID termination services to their business subscriber base.

Cut Your Telephony Costs Today

Most customers achieve 40–60% savings versus legacy circuits. Contact our team for a cost comparison and same-day provisioning.