SIP UID (SIP ID) – Legacy Extension Migration Support

Introduction

When migrating customers from legacy PBX systems to RingQ, many environments contain extension numbering formats that do not match modern PBX standards. Legacy PBX systems commonly use 2-digit, 3-digit, 4-digit, and 5-digit extensions. In real deployments, these numbers are already tied to IVR call flows, department routing, user habits, printed directories, hotel room numbers, and call center agent IDs.

Changing extension numbers during migration can create confusion, increase downtime, and delay user adoption. To solve this, RingQ provides SIP UID (SIP ID) support.

What is SIP UID (SIP ID)?

SIP UID (also shown in the UI as SIP ID) is the unique identifier used by RingQ for SIP registration, authentication, device mapping, and call routing. SIP UID is separate from the extension number.

Extension vs SIP UID in RingQ

RingQ uses two values for each user/endpoint:

• Extension (Primary Dial Number): The internal number users dial (example: 1000).
• SIP UID / SIP ID (Secondary Identifier): The unique SIP identity used internally for SIP registration (example: 100).

Important Note (RingQ Standard Behavior)

RingQ does not disable the internal extension 4-digit series. The Extension field remains the primary internal dialing method. SIP UID is used as a secondary number and may be displayed or referenced in dial plans, routing rules, legacy migration mapping, and SIP device registration scenarios.

Key Benefit: Supporting Legacy Digits Without Renumbering

With SIP UID support, RingQ allows customers to migrate from older systems while maintaining compatibility with mixed extension formats. This enables:

• Smooth migration without renumbering
• Support for 2 / 3 / 4 / 5 digit legacy extension mapping
• Reduced risk during cutover
• Faster adoption by end users

Example (RingQ UI)

Figure: RingQ Extension Configuration – Extension (Primary) and SIP ID (SIP UID Secondary)

Summary

RingQ keeps the extension number as the primary internal dial number. SIP UID (SIP ID) is used as a secondary unique SIP identifier to support legacy PBX migrations and flexible numbering formats without disrupting the standard 4-digit extension plan.