Hosted telephony or SIP trunks?

With hosted telephony, call control runs on a provider's platform and users connect through supported endpoints. With SIP trunks, the business retains a compatible phone system, often called a PBX, and connects it to a voice provider over IP. Both approaches still depend on appropriate connectivity, local networking and working user equipment. Moving call control does not remove those dependencies.

Begin with the existing PBX. Record its model, software version, support status, licences and maintenance arrangement. Establish who can change its configuration and recover it after a failure. A system that meets the business's requirements and remains supported may justify retaining that investment. A system with unavailable spares or knowledge held by one departing employee presents a different decision.

Then describe the actual calling requirements. Include how reception handles calls, how teams transfer callers, which numbers identify departments and where staff work. Ask users to demonstrate important workflows rather than relying on an old feature list. A shorter list of tested requirements gives both hosted and trunk-based proposals a clear basis for comparison.

A SIP trunk project needs compatibility checks across the PBX, its software, the proposed trunk configuration and any intermediary equipment. A product carrying a SIP label is not sufficient evidence that the required call flows work correctly. Include inbound and outbound calls, transfers, caller identification and the handling of concurrent calls in a deployment-specific test plan.

Hosted telephony shifts platform operation to the provider, but the business still needs clear responsibilities for user administration, endpoint support, local access and change approval. Ask how a new starter receives service, how a leaver loses access and who troubleshoots a problem that affects only one office. Compare the actual operating process, not just the number of boxes in the communications cabinet.

Netavo offers both hosted telephony and SIP trunking, alongside UK numbers and white-label softphones. The choice should follow the required operating model. Netavo's SIP trunks work with standards-based SIP PBXs.

For an IT or managed service provider, this responsibility map also determines the support offering. Be explicit about which organisation owns the PBX, endpoints, access circuit and voice platform, and where evidence goes when a fault crosses those boundaries.

Compare costs over a common planning period. For retained equipment, include maintenance, licences, replacement hardware, administration and the time needed to keep the system supported. For hosted service, include user requirements, endpoint replacement, training and operational administration. In both cases, account for access connectivity and the effort of preparing and transferring numbers.

Resilience also needs an end-to-end view. A hosted platform can remain available while a site's router or power supply fails. A retained PBX may introduce local equipment dependencies that need their own recovery arrangements. Ask each proposal to explain the behaviour under specific failures and have the design tested. Do not infer a particular backup or diversion feature from the service category alone.

Build a pilot around representative users and realistic calling patterns. Include someone who answers shared numbers, a remote worker if applicable and the person responsible for everyday administration. Record whether they can complete the expected tasks and how support handles a deliberately reported test problem. Resolve those findings before moving the main business number.

Plan number transfers, endpoint rollout and user communications as coordinated tasks. Confirm who makes the decision to proceed and what happens if acceptance fails. A recovery plan should describe available actions and supplier responsibilities without assuming an immediate reversal of a number transfer. The stronger proposal is the one that delivers the required calls with a support model the business understands and can sustain.