A guide to Voice Continuity
What happens if your business phone system goes down?
Most businesses have spent a lot of time thinking about disaster recovery.
Servers are backed up. Data is replicated. Cyber incident plans exist. Internet connectivity may have resilience built in. There are processes for getting people working again if a site becomes unavailable.
But there is one fairly simple question that can get missed: If your phone system went down tomorrow, which calls couldn't go down with it?
For some businesses, losing voice for an hour would be irritating. For others, it could mean customers can't reach support, reception disappears, orders can't be taken, operational teams lose a critical route into the business or key customer-facing numbers simply stop working.
That's where voice continuity comes in.
What is voice continuity?
Voice continuity is the ability to keep essential business communications operating when your normal phone service is disrupted.It doesn't necessarily mean duplicating your entire phone system.
A good starting point is much simpler: identify the numbers, users and teams the business genuinely cannot afford to lose, understand what happens to them during an outage today, and decide whether the protection already in place is good enough.
That distinction matters.
Your business might have 500 phone users, for example, but that doesn't automatically mean all 500 need exactly the same level of disaster recovery.
The critical question is what needs to keep working when something goes wrong?
Isn't having reliable internet enough?
Not necessarily.
Good connectivity is an important part of a resilient communications environment, but it isn't the same thing as having a voice continuity plan.
Ask a slightly different question:
What happens if the thing that fails isn't your internet connection?
And even where connectivity is the issue, what happens to the business-critical numbers while that problem is being resolved?
Resilience needs to consider the complete journey of a call, not just one component underneath it.
Can't employees just use their mobiles?
Sometimes. And for individual employees, that may be a perfectly adequate temporary workaround.
But it becomes more complicated when you're talking about:
- Main puiblished business numbers
- Reception
- Customer Service teams
- Helpdesks and support lines
- Sales or order lines
- Shared numbers and hunt groups
- Operational teams
- Contact Centres
A mobile phone may keep a person contactable. That doesn't necessarily keep the business service behind a critical number operational.
That's why identifying critical numbers and services is more useful than simply asking whether employees have another device they could use.
What is phone system failover?
At its simplest, failover means having an alternative way for calls to continue when the primary environment isn't available.
Exactly how that works depends on the technology and architecture involved.It might involve rerouting calls, using an alternative site or providing a secondary calling environment that can take over critical communications.
Modern cloud calling platforms can provide specific resilience capabilities. Cisco, for example, documents survivability options for Webex Calling that allow calling to continue when normal connectivity to Webex is unavailable. Its broader Webex Calling architecture also uses geographically redundant infrastructure and automatic failover between data centres.
The important thing for an IT team isn't simply being able to say “we have failover.” It's understanding what fails over, under which circumstances, and what the user or customer experiences when it happens.
Do we need disaster recovery for every phone user?
Not necessarily.
This is one of the reasons voice disaster recovery can be worth reviewing separately from a wholesale telephony project.
Start by categorising what you actually have. Which users or numbers are:
- Business critical: an outage would have an immediate operational or customer impact.
- Important: they need to be restored quickly, but a short interruption is manageable.
- Non-critical: they can reasonably wait for the primary service to be restored.
You can then design continuity around the business impact, rather than assuming everything needs identical protection.
For many organisations, that's a much more practical conversation.
We already have disaster recovery. Isn't that enough?
Possibly.
If you know exactly what happens to your critical voice services during an outage, you're comfortable with the recovery process and you've tested it recently, you may already be well protected.
But that leads to another useful question:
When did you last test it?
A disaster recovery plan written three years ago isn't necessarily the same thing as a disaster recovery capability you know works today.
People change. Sites change. Numbers change. Platforms change. Suppliers change. Infrastructure changes.Cisco's own Webex Calling business continuity approach, for example, includes scheduled testing and evaluation against different operational failure scenarios.
Your organisation doesn't necessarily need an elaborate testing regime, but it should be able to answer with confidence:
- What are our critical communications?
- What happens if the primary service fails?
- What takes over?
- How quickly?
- Have we proved it works?
That last question is particularly important.
What is DR as a Service for Voice?
DR as a Service (Disaster Recover as a Service) applies the same principle organisations already understand from other areas of IT: instead of building and maintaining all of the secondary infrastructure yourself, a disaster recovery capability is provided as a managed service.
For voice, that can mean having a secondary cloud calling environment available to protect selected business-critical communications if the primary phone system becomes unavailable.
The important word there is selected.
This doesn't have to begin with replacing your existing telephony environment or moving every user onto another platform.
The conversation can start with something far more practical:
Where does Webex fit?
Webex can provide the cloud calling environment behind a voice continuity or DR design.
Cisco describes Webex Calling as being engineered for high availability, including geographic redundancy and automatic failover within its cloud infrastructure. It also provides survivability options designed to maintain calling capabilities during certain connectivity failures.
But that's the technology answer.
The business answer comes first.Before deciding what technology you need, you need to understand what you're trying to protect.
Five questions to ask about your voice continuity today
You don't need to start with a major technical assessment. Sit down with your IT and operational teams and ask:
- Which phone numbers, teams and users absolutely have to remain contactable?
- What happens to those calls if our primary phone system or connectivity becomes unavailable?
- What resilience, failover or disaster recovery do we already have?
- When did we last test it?
- If there is a gap, how long could the business realistically cope?
If everyone around the table can answer those confidently, you're in a good place.
If the answers involve “I think…”, “it should…” or “we'd probably…”, it's probably worth taking a closer look.
Voice continuity isn't about expecting the worst. Nobody buys a phone system expecting it to fail.
And the point of disaster recovery isn't to suggest that it will. It's simply recognising that some communications matter too much to leave the answer to chance.
At CloudClevr, we use a 20-minute Voice Continuity Review to help organisations identify their critical voice services, understand what would happen to them during an outage and look at whether their existing resilience leaves any gaps.
There is no need to start with Webex, a replacement phone system or a major technology project. Start with one question:
If your phone system went down tomorrow, which calls couldn't?
If you're not completely sure what the answer is, that's probably the right place to begin. Not sure how protected your critical calls are?
If you’d like to understand a bit more about voice continuity, drop Lewis an email. He can talk you through it, answer any questions and take care of the rest.
