3CX SIP Trunk Integration with 2talk: Registration and IP Peering Setup

Learn how to connect your 3CX Phone System to 2talk using either SIP registration or static IP peering. This guide includes setup steps, outbound rules, and troubleshooting tips.

Table of Contents

3CX SIP Trunk Integration with 2talk

Connecting your 3CX Phone System to 2talk provides reliable SIP trunking for inbound and outbound calling. This guide explains how to configure both username/password registration and static IP SIP peering, suitable for business-grade VoIP environments.

Prerequisites

Before configuration, ensure the following:

  • 3CX version 18 or higher

  • A valid 2talk SIP trunk (via credentials or IP-based peering)

  • A known and stable public IP for your PBX

Option 1: SIP Registration (Username & Password)

Use this method when 2talk provides authentication credentials.

Trunk Setup

  1. Navigate to SIP Trunks → Add SIP Trunk

  2. Select Generic SIP Trunk

  3. Enter the following details:

    • Registrar: sip.2talk.com.au (or as provided)

    • Port: 5060 (UDP) or 5061 (TLS)

    • Authentication ID / Username: Provided SIP user ID

    • Password: Provided password

  4. Disable IP-based authentication

  5. Complete DID routing and codec configuration

Option 2: Static IP SIP Peering (No Registration)

This configuration is ideal for setups with static public IPs.

2talk Provisioning

Provide your 3CX public IP to 2talk for whitelisting.

Example:

  • Primary Peer IP: 10.10.10.00
  • Destination Proxy: 103.55.116.65:5060

3CX Configuration

General Tab

  • Registrar/Server: 103.55.116.65

  • Port: 5060

  • Authentication: Do not require – IP-based

  • Leave Username/Password blank

Options Tab

  • Transport Protocol: UDP

  • SRTP: Disabled

  • Re-register Timeout: 0

  • Public IP in SIP Header: Leave blank unless required

DID Numbers Tab

  • Add your numbers exactly as delivered (e.g., 61256385444)

  • Assign DIDs to extensions or ring groups

Outbound Rule Configuration

Use these recommended outbound rule settings:

Setting Value
Prefix: 0,00,13,+
Strip Digits: None
Prepend: Leave blank
Outbound Caller ID: 61756385444
Trunk: IP 2talk

Tip: Create an additional rule for specific dialing patterns (e.g., international prefixes).

Troubleshooting

Symptom Likely Cause Fix
No outbound call Number does not match an outbound rule Add or correct dial prefixes
No SIP INVITE seen on 2talk 3CX not matching a route Create fallback rule with X. prefix
“No user or outbound rule found” error Dialed number doesn’t match rule Review and test dial pattern
Outbound call fails with 403/404 Caller ID not valid Set 61756385444 as Outbound Caller ID
Inbound calls working, outbound not SIP trunk is inbound-only Enable “Allow outbound calls” in trunk

Final Checklist

Item Status
2talk has whitelisted your public IP ✅
3CX trunk set to “Do not require – IP based” ✅
Re-register timeout set to 0 ✅
DID added in 3CX exactly as received ✅
Outbound rule matches all formats used by staff

Summary

While 2talk is not listed as a certified 3CX SIP trunking provider, we have a large number of 3CX customers connecting successfully via both Registration and Peering:

  • Detailed connection guides
  • Support for both and
  • Proven success with many 3CX-based customers across Australia and the US