Call Routing Overview

This page explains how OPBX processes inbound calls and routes them to the correct destination within your organization.

Routing Overview

When a call arrives at a Cloudonix phone number assigned to your organization, OPBX determines where to route the call based on your configuration. This process happens in real-time using webhooks and CXML responses.

Call Flow

Step-by-Step Process

1. Caller dials a phone number (DID) assigned to your organization
2. Cloudonix receives the call and sends a webhook to OPBX
3. OPBX checks the inbound blacklist for the caller ID
4. OPBX looks up the routing configuration for the called number
5. OPBX evaluates the routing logic (business hours, IVR, etc.)
6. OPBX returns CXML instructions to Cloudonix
7. Cloudonix connects the call to the destination

Routing Destinations

OPBX can route calls to these destination types:

Destination	Description
Extension	A specific user's SIP phone
Ring Group	A group of extensions that ring together
IVR Menu	Interactive voice response menu
Business Hours	Time-based routing decision
Conference Room	Multi-party conference bridge
AI Assistant	AI-powered voice agent
AI Load Balancer	Distributed AI agent routing

Routing Chains

Destinations can cascade, creating complex routing chains:

Example: IVR to Ring Group to Fallback

1. Caller dials main number
2. IVR menu plays: "Press 1 for Sales"
3. Caller presses 1
4. Sales Ring Group rings
5. No one answers, call routes to Sales Manager extension

Example: Business Hours Branching

1. Caller dials support number
2. Business Hours checks current time
3. During business hours: routes to Support Ring Group
4. After hours: routes to Emergency IVR

Inbound Blacklist

Before routing, OPBX checks if the caller is on the inbound blacklist:

Action	Behavior
Silent Drop	Call ends without notification
Reject	Caller hears a busy or error message
Torment	Call connects to a "torment" conference (hold music loop)

tip

Use the blacklist to block spam callers, competitors, or harassing callers.

CXML

CXML (Cloudonix XML) is the language OPBX uses to instruct Cloudonix how to handle calls. OPBX generates CXML responses based on your routing configuration.

Common CXML Actions

Action	Purpose
Dial	Connect to an extension or external number
Connect	Bridge to a conference or AI agent
Gather	Collect digit input (for IVR)
Say	Play text-to-speech audio
Play	Play a recorded audio file
Conference	Join a conference room
Hangup	End the call

Example CXML Flow

Routing Configuration

Configure routing at these levels:

Phone Numbers (DIDs)

The entry point for all inbound calls. Each DID has a routing type and destination.

See Phone Numbers (DIDs) for details.

Ring Groups

Distribute calls to multiple extensions with various strategies.

See Ring Groups for details.

IVR Menus

Create interactive menus for caller self-service.

See IVR Menus for details.

Business Hours

Route based on time of day and day of week.

See Business Hours for details.

Best Practices

Design for the Caller

• Keep IVR menus short and clear
• Always provide a "speak to someone" option
• Minimize the number of steps to reach a human

Plan for Failures

• Configure fallbacks at every routing level
• Test what happens when destinations are busy or unavailable
• Have a "catch-all" destination for edge cases

Document Your Routing

• Maintain a diagram of your call flows
• Label phone numbers with their purpose
• Review routing regularly for obsolete configurations

Test Changes

• Test routing changes during low-traffic periods
• Verify both open and closed hours routing
• Check IVR digit options after updates