# Reliable Communication with Webex Calling

> What still works at a site when it loses its connection to cloud call control, what does not, and how survivability is decided site by site.

*Source: https://trybussolutions.com/reliable-communication-with-webex-calling/ · Trybus Solutions · Chattanooga, TN · 423-633-1817 · info@trybussolutions.com*

- [Home](https://trybussolutions.com/)
- Company[About us](https://trybussolutions.com/about-us/)
- [Careers](https://trybussolutions.com/careers/)
- Solutions[Collaboration](https://trybussolutions.com/collaboration-unified-communications/)
- [Networking & Connectivity Solutions](https://trybussolutions.com/networking-connectivity/)
- [Cybersecurity Solutions](https://trybussolutions.com/cybersecurity/)
- [Cloud & Infrastructure](https://trybussolutions.com/cloud-and-infrastructure/)
- [Governance, Risk & Compliance](https://trybussolutions.com/governance-risk-compliance/)
- [Digital Workplace](https://trybussolutions.com/digital-workplace/)
- Services[Implementation & Migration](https://trybussolutions.com/implementation-migration/)
- [Managed Services & Support](https://trybussolutions.com/managed-services-and-support/)
- [Trybus Connect](https://trybussolutions.com/trybus-connect/)
- Industries[Enterprise](https://trybussolutions.com/enterprise/)
- [Education](https://trybussolutions.com/education/)
- [Healthcare](https://trybussolutions.com/healthcare/)
- [Financial Services](https://trybussolutions.com/financial-services/)
- [Retail](https://trybussolutions.com/retail/)
- [Public Sector](https://trybussolutions.com/public-sector/)
- [Tribal Organization](https://trybussolutions.com/tribal-organization/)
- [Resources](https://trybussolutions.com/resources/)
- [Partners](https://trybussolutions.com/partners/)
- [Home](https://trybussolutions.com/)
- Company[About us](https://trybussolutions.com/about-us/)
- [Careers](https://trybussolutions.com/careers/)
- Solutions[Collaboration](https://trybussolutions.com/collaboration-unified-communications/)
- [Networking & Connectivity Solutions](https://trybussolutions.com/networking-connectivity/)
- [Cybersecurity Solutions](https://trybussolutions.com/cybersecurity/)
- [Cloud & Infrastructure](https://trybussolutions.com/cloud-and-infrastructure/)
- [Governance, Risk & Compliance](https://trybussolutions.com/governance-risk-compliance/)
- [Digital Workplace](https://trybussolutions.com/digital-workplace/)
- Services[Implementation & Migration](https://trybussolutions.com/implementation-migration/)
- [Managed Services & Support](https://trybussolutions.com/managed-services-and-support/)
- [Trybus Connect](https://trybussolutions.com/trybus-connect/)
- Industries[Enterprise](https://trybussolutions.com/enterprise/)
- [Education](https://trybussolutions.com/education/)
- [Healthcare](https://trybussolutions.com/healthcare/)
- [Financial Services](https://trybussolutions.com/financial-services/)
- [Retail](https://trybussolutions.com/retail/)
- [Public Sector](https://trybussolutions.com/public-sector/)
- [Tribal Organization](https://trybussolutions.com/tribal-organization/)
- [Resources](https://trybussolutions.com/resources/)
- [Partners](https://trybussolutions.com/partners/)
- [Home](https://trybussolutions.com/)
- [Company](https://trybussolutions.com/about-us/)[About us](https://trybussolutions.com/about-us/)
- [Careers](https://trybussolutions.com/careers/)
- Solutions[Collaboration & Unified Communications](https://trybussolutions.com/collaboration-unified-communications/)
- [Networking & Connectivity Solutions](https://trybussolutions.com/networking-connectivity/)
- [Cybersecurity Solutions](https://trybussolutions.com/cybersecurity/)
- [Managed Services & Support](https://trybussolutions.com/managed-services-and-support/)
- [Governance, Risk & Compliance Solutions](https://trybussolutions.com/governance-risk-compliance/)
- [Cloud & Infrastructure](https://trybussolutions.com/cloud-and-infrastructure/)
- [Digital Workplace](https://trybussolutions.com/digital-workplace/)
- Services[Implementation & Migration](https://trybussolutions.com/implementation-migration/)
- [Architecture & Solution Design](https://trybussolutions.com/architecture-solution-design/)
- [Trybus Connect](https://trybussolutions.com/trybus-connect/)
- [Trybus Hub](https://trybussolutions.com/trybus-hub/)
- Industries[Enterprise](https://trybussolutions.com/enterprise/)
- [Education](https://trybussolutions.com/education/)
- [Healthcare](https://trybussolutions.com/healthcare/)
- [Financial Services](https://trybussolutions.com/financial-services/)
- [Retail](https://trybussolutions.com/retail/)
- [Public Sector](https://trybussolutions.com/public-sector/)
- [Tribal Organization](https://trybussolutions.com/tribal-organization/)
- [Partners](https://trybussolutions.com/partners/)
- [Resources](https://trybussolutions.com/resources/)
- [Shop](https://shop.trybussolutions.com/)
- [Contact Us](https://trybussolutions.com/contact-us/)
- [Customer Portal](https://trybussolutions.myportallogin.com)
- [Home](https://trybussolutions.com/)
- [Resources](https://trybussolutions.com/resources/)
- Reliable Communication with Webex Calling

# Reliable Communication with Webex Calling

January 29, 20255 min readCollaboration

A cloud calling platform moves call control out of your building and into a provider’s data centers. That is the point of it. It works until a site loses its path to those data centers, and then every phone on every desk is powered, on the network, and unable to place a call. Which parts of the [phone system](https://trybussolutions.com/collaboration-unified-communications/) a site keeps at that moment is a design question. Almost nobody asks it early enough.

## **What a site loses, and what it keeps**

Survivability is the general name for keeping some call handling alive locally when the cloud cannot be reached. Hardware inside the building holds enough configuration to register the local phones and route calls itself, and takes over when it stops hearing from the cloud. What that hardware can do is much narrower than what the cloud does. The gap is the design conversation.

### **The services degrade differently**

Each of these behaves its own way once the site is cut off, and a business almost never values them equally. Ranking them is most of the work.

- **Calls between phones at the site** Normally preserved. The local hardware registers the phones and connects them to each other, so extension dialing inside the building keeps working.
- **Calls to and from the public network** Only if the site has its own path to a carrier. Without local circuits or a local trunk terminating in the building, the site can talk to itself and to nobody else.
- **Emergency calling** Not negotiable, and the reason many sites end up with local carrier access at all. Establish what location information reaches the call taker in degraded mode, and where it comes from.
- **Hunt groups, auto attendants and call queues** Application logic living in the cloud. Local hardware can hold a simplified version, maintained separately. A caller who normally hears a menu may instead ring one desk.
- **Voicemail** Generally a cloud service. Expect unanswered calls to ring out instead of reaching a mailbox, and no message waiting indication until the site reconnects.
- **Call recording** Almost always a cloud service, and almost always the one nobody checks. If a team is recorded for compliance, decide in advance whether it may take calls at all without it.
- **Directory lookup, presence and softphones** All of them depend on reaching the cloud. Users fall back to desk phones and to the numbers they happen to know.

## **Provider redundancy is a different problem**

Providers run their platforms across multiple data centers and publish how they handle losing one. That redundancy is real. It also has very little to do with the failure most organizations actually meet, which is a single building losing its circuit, and a contractor cutting fiber outside a branch office does not care how many data centers the provider operates. Platform redundancy protects the platform. Survivability protects the site.

### **What survivability requires at every site that has it**

- **Hardware in the building** An appliance or router carrying the local call control function. It takes rack space, draws power and needs support like everything else in the closet.
- **A local path to the carrier** A trunk terminating on that hardware, or analog or digital circuits. Without one, survivability delivers internal dialing and nothing more.
- **Configuration that does not drift** The local copy has to follow every change to users, numbers and routing. How much of that is automatic varies by platform. Ask before you buy.
- **Cost that recurs, per site** Hardware, licensing, the circuit and the support behind them, at every address that has it. That arithmetic is why almost nobody deploys it everywhere.

### **Which sites actually need it**

Survivability is decided one site at a time. The question is what an hour without external calling costs at that address, and the answer is very different for a head office where everybody carries a mobile phone, a distribution center that runs on handhelds, and a clinic where the main number is how patients reach a nurse. A back office doing internal work can wait. A site taking customer orders by phone, or where somebody may one day need to call an ambulance, cannot. Most organizations end up protecting a handful of locations and accepting the risk everywhere else.

For a good number of sites the honest recommendation is to skip it. If the building can take a second circuit from a different carrier for less than a gateway, a trunk and their support cost, that money usually buys more availability. We will say so, and it costs us the larger sale.

What happens to a site when the circuit drops?

Site survivability is the question most cloud calling designs answer too late. We design it in at the start, then test it before you have to depend on it.

On the collaboration work we run, survivability is settled during design rather than discovered after cutover:

- **A per-site decision on the record** Which sites get it, which do not, and why, so the list can be revisited when the business changes.
- **A written degraded mode** One page per surviving site saying what works and what does not, in language the help desk and the site manager can both act on.
- **A failover test with recorded results** The connection is dropped deliberately, behavior is checked against that page, and every difference is fixed or accepted in writing.

### **Prove it before you depend on it**

There are two ways to learn what a survivability design really does. One of them is an outage. The other is a deliberate failover on a scheduled evening, which takes a couple of hours and tells you which services came back, which came back changed, and which never appeared at all. Most sites produce at least one surprise. If nobody has proved what happens when one of your sites goes dark, that test is where the conversation starts.

[Contact Us](https://trybussolutions.com/contact-us/)

## About the Author

**Brandon Kinsey**

VP, Collaboration Solutions

Trybus Solutions

## Keep reading

- [CollaborationCisco Desk Phone 9800 Series: What Decides the Model Mix7 min read](https://trybussolutions.com/actionable-insights-for-your-business/)
- [Unified CommunicationsWhat is UC? Why Does Your Business Need It?8 min read](https://trybussolutions.com/what-is-uc-why-does-your-business-need-it/)
- [MigrationAnalog Endpoints and Cloud Calling8 min read](https://trybussolutions.com/analog-endpoints-cloud-calling-migration/)

## Test your survivability design before you need it

Trybus Solutions designs site survivability for cloud calling, then proves it with a documented failover test so you know exactly what happens when a circuit goes down.

Or call [423-633-1817](tel:+14236331817) · [info@trybussolutions.com](mailto:info@trybussolutions.com)