DIDs/DDIs Management Doc

What are DIDs/DDIs?

DID (Direct Inward Dialing) or DDI (Direct Dial-In) numbers are phone numbers that directly reach specific destinations in your PBX without going through an operator or auto-attendant. They're the public phone numbers your customers dial to reach your business.

Understanding DIDs

Key Concepts:

DID/DDI Number: A public phone number assigned to your business (e.g., +1-555-123-4567)
DID Pool: A range of consecutive numbers (e.g., +1-555-123-4567 through +1-555-123-4599)
Main Number: Primary business phone number
Direct Lines: Numbers that reach specific extensions or departments

Common Uses:

Company main line
Department direct lines (Sales, Support, HR)
Individual employee direct numbers
Fax lines
Emergency callback numbers

Add a DID

Navigate to DIDs

Go to Settings > Trunks > DIDs > Click Add DID

Enter DID Information

Required Fields:

DID Number: The phone number (e.g., +15551234567)
DID Name: Descriptive label (e.g., "Main Office", "Sales Direct", "Support Line")
Trunk: Select the trunk this DID is associated with

Naming Convention

Use descriptive names that identify the purpose:

"Main-Office-Line"
"Sales-Department"
"Support-Hotline"
"John-Smith-Direct"

Number Formatting Options:

E.164 Format (Recommended):

International standard format
Includes country code
No spaces or special characters
Example: +15551234567 (US), +441234567890 (UK)

Local Format:

Without country code
Example: 5551234567 (US 10-digit)

Display Format:

For display purposes only
Can include formatting: +1 (555) 123-4567
System uses normalized format for routing

Important

Use E.164 format for consistency and international compatibility. The system automatically normalizes numbers for routing.

Associating DIDs with Trunks:

Trunk Selection: Choose which trunk this DID belongs to
Provider Assignment: DID must be provisioned by your trunk provider
Multiple Trunks: Same DID can't be assigned to multiple trunks

Provider Provisioning

Before adding a DID to your PBX:

Purchase/provision the DID from your trunk provider
Confirm the DID is active on your trunk
Add the DID in PBX to match provider configuration

Verification: After adding, test inbound calls to ensure DID routes correctly through the assigned trunk.

Configure Optional Settings

Outbound Caller ID:

Enable as Outbound Caller ID: Allow this DID for outbound calling
Set as Default: Use this DID by default for outbound calls
Per-Extension: Assign DID to specific extensions for their outbound caller ID

Use Case

Enable DIDs as outbound caller ID to display your business number instead of the trunk's default number when making calls.

Number Manipulation (Advanced):

Strip Digits: Remove leading digits (e.g., strip country code)
Prepend Digits: Add digits to the beginning
Number Rewrite: Transform number format

Example Scenarios:

Provider sends 5551234567, you want +15551234567
Remove international prefix for internal routing
Normalize different number formats

When Needed

Most configurations don't require number translation. Only use if your provider sends numbers in a non-standard format.

Failover Destination:

Configure where calls go if primary destination is unavailable:

Alternative extension
Voicemail
Auto-attendant
External number

Business Continuity

Set up failover to ensure no calls are lost when primary destination is busy, offline, or experiencing issues.

Save and Test

Click Save to add the DID.

DID Added

The DID is now configured. Next, create an inbound route to direct calls to the appropriate destination.

Import DIDs

For bulk DID management, use the import feature to add multiple numbers simultaneously.

Navigate to Import

Go to Settings > Trunks > DIDs > Click Import DIDs

Prepare Import File

CSV File Requirements:

Format: Comma-separated values (.csv)
Encoding: UTF-8
Headers: First row must contain column names

Required Columns:

did_number: Phone number (E.164 format recommended)
did_name: Descriptive name
trunk_name: Trunk name (must match existing trunk)

Optional Columns:

caller_id_enabled: true/false
notes: Additional information

Example CSV:

did_number,did_name,trunk_name
+15551234567,Main Office,TheVoĉo-Main-Trunk
+15551234568,Sales Department,TheVoĉo-Main-Trunk
+15551234569,Support Line,TheVoĉo-Main-Trunk

Excel Spreadsheet (.xlsx):

First row: Column headers
Subsequent rows: DID data
Save as .xlsx or export to CSV

Column Layout:

did_number	did_name	trunk_name
+15551234567	Main Office	TheVoĉo-Main-Trunk
+15551234568	Sales Dept	TheVoĉo-Main-Trunk

Tip

Excel is easier for editing large number ranges. Export to CSV before importing to PBX.

Sample Import Data:

Scenario 1: Department Direct Lines

did_number,did_name,trunk_name
+15551234567,Main Reception,Primary-Trunk
+15551234570,Sales Direct,Primary-Trunk
+15551234571,Support Direct,Primary-Trunk
+15551234572,HR Direct,Primary-Trunk

Scenario 2: DID Range for Employees

did_number,did_name,trunk_name
+15551234580,John Smith Direct,Employee-DIDs
+15551234581,Jane Doe Direct,Employee-DIDs
+15551234582,Bob Johnson Direct,Employee-DIDs

Bulk Numbering

Use spreadsheet auto-fill to quickly generate sequential number ranges.

Upload and Validate

Click Choose File and select your CSV/Excel file
Click Upload to import
Review the validation results
Fix any errors (duplicate numbers, invalid trunks, etc.)

Validation Errors

Common errors:

Duplicate DID numbers
Non-existent trunk names
Invalid number format
Missing required fields

Confirm Import

After validation passes, click Confirm Import.

Import Complete

All DIDs have been added. Review the DID list to verify accuracy, then create inbound routes for the new numbers.

Manage DIDs

DID List Overview:

Navigate to Settings > Trunks > DIDs to view all configured DIDs.

Information Displayed:

DID Number
DID Name
Associated Trunk
Caller ID Status (enabled/disabled)
Inbound Route (if configured)

Filtering:

Search by DID number or name
Filter by trunk
Sort by number, name, or trunk

Quick Search

Use the search box to quickly find specific DIDs by number or partial number match.

Modify DID Settings:

Click the Edit icon next to the DID
Update any field:
- DID Name
- Trunk assignment
- Caller ID settings
- Failover options
Click Save

Bulk Edit:

Select multiple DIDs using checkboxes
Click Bulk Edit
Apply changes to all selected DIDs

Trunk Changes

Changing a DID's trunk assignment may affect inbound routing. Verify inbound routes after trunk changes.

Remove DIDs:

Single DID:

Click Delete icon next to the DID
Confirm deletion

Multiple DIDs:

Select DIDs using checkboxes
Click Delete Selected
Confirm deletion

Warning

Deleting a DID removes it from the PBX but doesn't cancel it with your provider. Remember to:

Remove inbound routes using this DID
Contact provider to port/cancel the number if no longer needed

Impact of Deletion:

Inbound routes using this DID will fail
Caller ID configurations using this DID will need updating
Number becomes unavailable for routing

Bulk Management Operations:

Available Actions:

Bulk Import: Add multiple DIDs from CSV
Bulk Export: Download all DIDs to CSV
Bulk Edit: Modify multiple DIDs simultaneously
Bulk Delete: Remove multiple DIDs at once
Bulk Assignment: Assign DIDs to trunk or caller ID settings

Best Practices:

Export before bulk changes: Create backup of current configuration
Test on small subset: Verify bulk changes work as expected
Use consistent naming: Makes bulk management easier
Document changes: Note what was changed and why

Export Use Cases

Export DIDs to:

Create configuration backups
Audit DID assignments
Plan inbound routing
Share with team members
Migrate to new PBX

DID Assignment Strategies

Main Business Number Strategy:

Setup:

One primary DID for company
Routes to auto-attendant or receptionist
Prominently displayed on website, business cards
Used for outbound caller ID

Configuration:

Add main DID (e.g., +1-555-COMPANY)
Create inbound route to auto-attendant
Configure as default outbound caller ID
Set up after-hours handling

Advantages:

Single memorable number for customers
Professional image
Easy to market and remember
Centralized call handling

Best Practice

Even with direct lines, always have a main number that reaches a person or well-designed auto-attendant.

Department Direct Lines:

Setup:

Separate DIDs for each department
Direct access bypassing auto-attendant
Listed on website directory

Example Configuration:

Main: +1-555-123-4567 → Auto-attendant
Sales: +1-555-123-4570 → Sales Ring Group
Support: +1-555-123-4571 → Support Queue
HR: +1-555-123-4572 → HR Extension

Advantages:

Faster customer access to right department
Better call tracking and analytics
Department-specific caller ID
Improved customer experience

Implementation:

Add DID for each department
Create inbound routes to ring groups/queues
List numbers on website contact page
Use department DIDs for outbound caller ID

Customer Experience

Department direct lines reduce customer frustration by eliminating IVR menu navigation for repeat callers.

Individual Direct Lines:

Setup:

Unique DID for each employee or key personnel
Direct to extension without IVR
Used on business cards and email signatures

Who Gets Direct Lines:

Executives and managers
Sales representatives
Customer success managers
Technical support specialists
Anyone with frequent external communication

Configuration:

Add DIDs for each person
Create inbound routes to their extensions
Set up voicemail for missed calls
Configure mobile/home failover if needed
Enable as their outbound caller ID

Advantages:

Professional presence
Easy for clients to reach specific people
Better work-life balance (dedicated work number)
Call tracking per employee

Cost Consideration

Direct lines typically cost $1-5 per number per month. Calculate ROI based on improved customer access and employee productivity.

DID Pool Management:

What is a DID Pool? A range of consecutive numbers for flexible assignment (e.g., +1-555-123-4500 through +1-555-123-4599).

Use Cases:

Growing Teams: Add employees without ordering new numbers
Hot Desking: Reassign numbers as needed
Temporary Projects: Allocate numbers for campaigns
Multi-Location: Different number ranges per office

Management Strategy:

Reserve Ranges:
- Main: 4500-4509
- Sales: 4510-4529
- Support: 4530-4549
- General: 4550-4599
Assignment Policy:
- Document who gets which numbers
- Track unused numbers
- Reclaim numbers when employees leave
- Maintain spreadsheet of assignments
Bulk Import:
- Import entire range at once
- Assign as needed
- Leave unrouted DIDs inactive

Planning Tip

Order DID pools with room for growth. It's easier to have spare numbers than to order more later and deal with non-consecutive ranges.

Advanced DID Features

Porting Existing Numbers:

What is Number Porting? Transferring your existing phone numbers from one provider to another while keeping the same numbers.

Porting Process:

Request LOA (Letter of Authorization) from new provider
Submit Port Request with current provider details
Wait for Approval (typically 7-14 business days)
Port Completion on scheduled date
Configure in PBX on port date

Requirements:

Account number from current provider
Account PIN/password
Billing telephone number (BTN)
Service address
Authorized signature

Important Notes:

Don't cancel old service until port completes
Port entire account or individual numbers
Porting timeline varies by country/provider
Testing window after port before cutover

Critical

Coordinate port timing with your provider. Canceling service before port completion results in losing your numbers permanently.

Local Presence with Virtual Numbers:

What are Virtual Numbers? DIDs in different geographic areas that route to your centralized PBX, creating local presence without physical offices.

Use Cases:

Remote Sales: Local numbers in target markets
Multi-Location Business: Different area codes per location
International Presence: Numbers in multiple countries
Testing Markets: Try locations before opening offices

Example Setup:

Headquarters in New York: +1-212-555-0100
Virtual Dallas office: +1-214-555-0100
Virtual Los Angeles: +1-323-555-0100
All route to same PBX, different ring groups

Benefits:

Local caller rates for customers
Professional multi-location image
No physical office needed
Easy to add/remove markets

Customer Trust

Studies show customers are more likely to call local numbers. Virtual numbers increase response rates by 30-40%.

Choosing Number Types:

Geographic Numbers (Local):

Format: Area code + local number (e.g., +1-555-123-4567)
Cost: Lower monthly cost
Best For: Local businesses, specific market presence
Caller Cost: Local or long distance depending on caller location
Perception: Community business, local presence

Toll-Free Numbers:

Format: 800, 888, 877, 866, 855, 844, 833 prefixes (US)
Cost: Higher monthly + per-minute charges
Best For: National businesses, customer service lines
Caller Cost: Free for callers
Perception: Established business, customer-friendly

Decision Matrix:

Business Type	Recommended	Reason
Local Business	Geographic	Customers are local, lower cost
E-commerce	Toll-Free	National reach, professional
Support Line	Toll-Free	Customer convenience
Sales Team	Both	Toll-free main, local for reps

Hybrid Approach

Many businesses use both: toll-free for main line, geographic for departments and direct lines. Best of both worlds.

Global Phone Numbers:

International DID Capabilities:

Numbers in 60+ countries
Local presence worldwide
No international office needed
All route to your PBX

Common Scenarios:

UK Business with US Clients: Add US DIDs
E-commerce Expansion: DIDs in new markets
Support Coverage: 24/7 local numbers globally
International Sales: Local numbers per region

Configuration Considerations:

Number Format: Use E.164 (+country code) format
Time Zones: Consider caller timezone for routing
Languages: Auto-attendant in local languages
Regulations: Comply with local telecom laws
Emergency: Some countries require physical address

Provider Availability: Not all trunk providers offer all countries. Check with your provider for:

Available countries
Setup fees
Monthly costs
Porting capabilities
Regulatory requirements

Regulatory Compliance

Some countries (e.g., Germany, Belgium) require business registration or physical address to provision local numbers. Research requirements before ordering.

Best Practices

DID Management Recommendations

Follow these best practices for efficient DID management and optimal call routing.

Organization

Consistent Naming: Use clear, standardized naming conventions
- Format: [Purpose]-[Department/Name]-DID
- Example: Main-Office-DID, Sales-John-Smith-DID
Documentation: Maintain DID inventory
- Spreadsheet with DID, assignment, purpose
- Update when changes occur
- Include provider account details
- Note porting dates and history
Number Ranges: Use logical grouping
- Group by department
- Sequential assignment within groups
- Reserve ranges for future growth

Routing

Test All DIDs: Verify each DID routes correctly
- Test from external number
- Verify inbound route destination
- Check after-hours handling
- Test failover scenarios
Failover Configuration: Always set failover destinations
- Voicemail for direct lines
- Auto-attendant for main numbers
- Alternative extensions for departments
Time-Based Routing: Consider business hours
- Different routing during/after hours
- Holiday schedules
- Lunch break handling

Security

Monitor Usage: Track unusual patterns
- Unexpected countries
- High call volumes
- Off-hours activity
- Short-duration calls
Caller ID Restrictions: Control outbound caller ID
- Only enable necessary DIDs
- Restrict per-extension
- Monitor unauthorized usage
Rate Limiting: Protect against toll fraud
- Limit calls per DID per hour
- Alert on threshold violations
- Block suspicious patterns

Cost Management

Regular Audit: Review DID inventory quarterly
- Identify unused numbers
- Cancel unnecessary DIDs
- Consolidate where possible
Port vs New: Compare costs
- Porting fees vs new number costs
- Consider customer recognition
- Marketing material updates
Provider Comparison: Evaluate DID costs
- Monthly per-DID fees
- Setup costs
- Porting fees
- International availability

Troubleshooting

DID isn't receiving calls?

Diagnostic Steps:

Verify DID is Active:
- Check DID list shows the number
- Confirm trunk assignment
- Contact provider to verify DID is provisioned
Check Trunk Status:
- Go to Settings > Trunks
- Verify trunk is registered/connected
- Test with another DID on same trunk
Verify Inbound Route:
- Check inbound route exists for this DID
- Verify DID pattern matches exactly
- Test route with wildcard pattern
Test Trunk:
- Make outbound call to verify trunk works
- Check trunk provider portal for issues
- Review SIP logs for registration errors

Provider Provisioning

Most "no inbound calls" issues are provider-side. The DID may not be active on your trunk, or provider configuration may be incorrect.

Calls route to wrong destination?

Common Causes:

Inbound Route Mismatch:
- Multiple routes match the DID
- Pattern matching is too broad
- Route priority is incorrect
Pattern Matching:
- Check DID pattern in inbound route
- Verify exact match or wildcard
- Review pattern precedence
Time Conditions:
- Route has time restrictions
- After-hours routing active
- Holiday schedule interfering

Resolution Steps:

Review all inbound routes
Check for overlapping patterns
Verify route priority order
Test during different times
Simplify patterns for troubleshooting

Quick Fix

Temporarily create a specific route with highest priority for the problematic DID to isolate the issue.

Caller ID not displaying correctly?

Inbound Caller ID Problems:

Provider sends wrong format
Number translation needed
Caller ID name not passed
International format issues

Solutions:

Check provider sends caller ID
Configure number translation rules
Verify E.164 format handling
Contact provider about CNAM (Caller Name)

Outbound Caller ID Problems:

DID not enabled for caller ID
Extension not assigned to DID
Provider rejects custom caller ID
Carrier overrides caller ID

Solutions:

Enable DID for outbound caller ID
Assign DID to extension/route
Verify provider allows caller ID manipulation
Check provider's CNAM registration

Provider Restrictions

Some providers don't allow custom caller ID for fraud prevention. You can only use DIDs registered to your account.

Number porting issues?

Common Port Issues:

Port Rejected:
- Incorrect account information
- BTN doesn't match records
- Account has outstanding balance
- Authorization signature invalid
Port Delayed:
- Missing information
- Manual review required
- Provider coordination issues
- Weekend/holiday timing
Partial Port:
- Some numbers ported, others didn't
- Account structure mismatch
- Individual number restrictions
Service Interruption:
- Old provider disconnected early
- New provider not ready
- Timing coordination failed

Prevention:

Submit complete, accurate information
Verify account details with current provider
Schedule port during low-traffic period
Test new service before port date
Have backup plan (temporary numbers)

If Port Fails:

Contact new provider immediately
Request emergency reconnection from old provider
File FCC complaint if unresolved (US)
Consider temporary forwarding solution

Critical

Always maintain service with old provider until port completes. Early cancellation results in permanent number loss.

Understanding DIDs

Add a DID

Navigate to DIDs

Enter DID Information

Configure Optional Settings

Save and Test

Import DIDs

Navigate to Import

Prepare Import File

Upload and Validate

Confirm Import

Manage DIDs

DID Assignment Strategies

Advanced DID Features

Best Practices

Organization

Routing

Security

Cost Management

Troubleshooting

Next Steps

Create Inbound Routes

Configure Outbound Caller ID

Set Up Auto-Attendant

Emergency Numbers

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