Connect enterprise voice to the PSTN.
SIP connectivity for enterprises retaining their PBX, SBC and communications applications.
Known calling workflows
Tested network boundary
Coordinated cutover
Migrate the connection without overlooking dependencies.
The operating model
An enterprise voice estate can include more than desk phones. Inventory main numbers, direct lines, contact-center services and any attached systems before changing trunks. Identify which teams own the PBX, SBC, firewall and service desk so an issue during cutover reaches the right person.
Move through a defined acceptance window and retain a practical recovery path. Test representative locations and call flows before retiring the previous connection. Emergency-calling arrangements and specialist devices require a specific suitability review; do not infer their behavior from a normal voice test.
Where VirPhone fits
Map locations, number dependencies and migration windows before retiring existing trunks.
Define the handoff
Enterprise PBX, approved SBC and SIP interconnect form the path. Review alternate routes against continuity requirements.
- 01Your applications
- 02Your voice infrastructure
- 03VirPhone service
- 04PSTN connectivity
Plan around your operation
Inventory numbers, calling patterns, analog dependencies and emergency-calling requirements. Confirm suitability before scheduling a migration.
Continue the technical review
Voice service
Explore the relevant connection.
Explore Voice serviceInterconnect
Review signaling and media.
Explore InterconnectOnboarding
Prepare a commercial and technical inquiry.
Explore OnboardingWhat to review with your team
| Review area | What to establish |
|---|---|
| Discovery | Locations; numbers; systems; peak demand and business-critical flows. |
| Cutover | Acceptance owner; test schedule; recovery decision and user support. |
| Next step | Share the proposed architecture, traffic profile and required service boundary. |
Before the next step
What should our technical team prepare?
Locations; numbers; systems; peak demand and business-critical flows. Include known application dependencies and the people responsible for testing.
Connect an existing voice estate with a defined handoff
An enterprise SIP project often starts with a PBX that already supports established workflows. Inventory that environment before changing the carrier: SBC software, public addressing, sites, numbers, queues and any devices with special calling requirements. Keep application features separate from the trunk service scope.
Plan migrations around how people work. A branch with a reception group may need different tests from a headquarters with contact-center queues. Identify local internet and power dependencies as part of the continuity discussion; a carrier connection cannot remove every dependency at the customer site.
Make cutover reversible where the design permits
Agree a testing window, the person authorized to accept service and the conditions for pausing a migration. Coordinate number-porting dates with the receiving system configuration. Keep old service active until the agreed completion and investigate remaining number dependencies before cancellation.
Start with review enterprise sip connectivity. Describe the service you operate, the part of the call path you want to change and the person responsible for technical acceptance. That gives the first discussion a concrete scope.
A practical question
What information should the PBX team bring?
The PBX and SBC versions, site topology, number inventory and normal call flows. Include devices or applications that require separate acceptance tests.