Business telephony is no longer just about making calls. Today, it’s about seamlessly connecting people, data, and workflows across offices, devices, and geographies. Whether your organisation is evaluating a cloud-hosted phone system, a Cisco on-premises PBX, or a hybrid model, the right choice will impact mobility, customer experience, compliance, and scalability.
This blog explains the options clearly and practically, focusing on real-world integration, licensing, and migration considerations so you can make an informed decision.
Business Telephony Evolution:
Legacy PBX systems once dominated business telephony, relying on physical servers and desk phones. However, the shift to VoIP and cloud PBX is transforming communications.
Cloud systems offer flexibility, cost efficiency, and integration with collaboration tools such as Microsoft Teams and Google Workspace. They also remove the need for businesses to manage complex on-premises hardware.
How Cloud Phone Systems Work?
A cloud phone system is made up of several connected components that work together to deliver business telephony:
Cloud Phone System (PBX):
The central “brains” of the platform. It manages call routing, voicemail, auto-attendants, conferencing, and integrations with chat or meeting apps.Office Router & Internet Connection:
All voice traffic travels securely over your business’s internet. Quality of Service (QoS) ensures calls remain clear and prioritised even when the network is busy.PSTN (Public Switched Telephone Network):
The global telephone network that connects your system to mobiles, landlines, and international numbers. Cloud providers use SIP trunks or carrier partners to bridge between VoIP calls and the PSTN.Devices (Endpoints):
Staff connect through desk IP phones (e.g., Yealink, Poly, Cisco) or softphone apps (Teams, Webex, Google Voice) on desktops and mobiles. These endpoints link directly into the cloud PBX for seamless calling.
Who Are the Main Providers?
The three leading options for cloud phone systems are Cisco Webex, Microsoft Teams Phone, and Google Voice:
Cisco (Webex Calling / CUCM): A longstanding enterprise provider offering both cloud and on-premises options, along with strong networking and SBC integration.
Microsoft (Teams Phone): Ideal for businesses already using Microsoft 365, offering multiple PSTN connectivity choices.
Google (Google Voice): A simple, app-first solution suited to mobile and remote-first teams, though with more limited PSTN coverage.
Here’s a quick comparison of the three leading providers, showing how they differ in licensing, connectivity, device support, and overall fit for different business needs.
| Aspect | Cisco (Webex / CUCM) | Microsoft (Teams Phone) | Google (Google Voice) |
|---|---|---|---|
Licensing | Webex Calling license (cloud) or CUCM (on-prem). | M365 E5 (includes Phone System) or E3/Business Standard + Phone System add-on. | Google Workspace + Google Voice license. |
PSTN Connectivity | SIP trunk via telco, or Cisco CUBE SBC. | Microsoft Calling Plan, Operator Connect, or Direct Routing (own carrier). | Carrier partners (coverage limited in AU). |
Devices | Cisco phones + Webex app. | Teams-certified phones (Yealink, Poly, AudioCodes) + Teams app. | Primarily app-based. Limited desk phone support. |
Network Dependence | Cisco supplies networking/QoS hardware. | Relies on ISP. Third-party firewall/router support. | Relies on ISP. No network hardware. |
Security | Cisco CUBE SBC, enterprise-grade. | SBC is required only for Direct Routing. | Google-managed PBX security. |
Limitations | Complex for SMBs; geared to enterprise. | Licensing requirements: best for Microsoft 365 users. | Fewer enterprise features, less PSTN support outside the US/EU. |
Why Elto is Your Preferred Partner
The comparison shows that each provider, Cisco Webex, Microsoft Teams Phone, and Google Voice, has its own strengths depending on business size, existing platforms, and connectivity needs. What’s consistent, however, is the industry-wide shift: the era of managing complex on-premises PBX hardware is ending, and cloud-hosted telephony has become the new standard.
This transition can raise practical questions around devices, number porting, carrier plans, and security. That’s where Elto IT Services makes the difference. We go beyond product comparisons to deliver end-to-end support from hardware and software procurement to internet services to the management of VoIP platforms. Our role is to ensure your move to cloud telephony is seamless, secure, and aligned with your business goals.
With the foundations in place, let’s address some of the most common questions businesses ask when considering cloud telephony.
FAQs
Only if you want desk phones, ensure they are certified. Otherwise, use PC/mobile apps.
Yes. Numbers can be ported to the provider or retained via SIP trunks/Direct Routing.
Direct Routing allows you to keep your carrier’s plans. Microsoft/Google rates apply if using their plans.
Reliable, business-grade internet with Quality of Service (QoS) is essential.
Providers secure the PBX, but SBCs add an additional layer of protection for Direct Routing setups.
