Glossary · Phone system (PBX)
UCaaS
In one sentence
UCaaS (unified communications as a service) brings business telephony, video meetings, instant messaging and often file sharing together in one cloud service, billed per user and used from desk phones, computers or mobiles.
Also known as : UCaaS · unified communications as a service · unified communications · UCaaS platform
What is UCaaS?
In many businesses each communication tool arrived on its own: a phone system installed a decade ago, a video tool picked up during lockdown, a chat app one team chose, mobiles on a separate contract. UCaaS, unified communications as a service, puts these in a single service hosted in the cloud.
A UCaaS subscription usually covers:
- telephony, through a cloud PBX with numbers and extensions;
- video meetings and screen sharing;
- instant messaging and presence (available, on a call, away);
- desktop and mobile apps, including a softphone.
It differs from CCaaS, built for contact centres, and CPaaS, which gives developers building blocks rather than a finished product.
How it works
The provider hosts everything in its data centres. The business creates user accounts and pays a monthly fee per person. Each employee signs in from an IP phone, a laptop or a mobile and finds the same number, contacts and conversation history wherever they are.
Calls run as VoIP over the internet connection. There is no on-site PBX to install, patch or replace. The trade-off is that call quality depends on the network, so plan a fallback, such as diverting to mobiles or a backup 4G router, for when the line drops.
For many UK businesses the timing is set by the PSTN switch-off: as analogue and ISDN lines are withdrawn, replacing an old PBX with a cloud service is often simpler than moving it to SIP.
Example
A 30-person recruitment agency with offices in Birmingham and Dublin ran an ageing PBX in Birmingham, separate Irish lines and a consumer video app. It moves to UCaaS: every consultant has a direct UK or Irish number, calls between offices are internal, and client interviews run on video from the same tool. Consultants working from home take calls in the desktop app, and new starters are set up in minutes by the office manager.
UCaaS at Universal Telecom
The Universal Telecom virtual PBX is the telephony base of a UCaaS approach: extensions, IVR, queues, mobile app and webphone. Add global numbering for offices abroad and business mobile for teams on the move.
Frequently asked questions
Is a cloud PBX the same as UCaaS?
A cloud PBX is the telephony core of UCaaS. A full UCaaS service adds video meetings, team chat and presence on top. Some cloud PBX services include those features, others integrate with tools you already use.
Is Microsoft Teams a UCaaS?
Teams covers video, chat and files. For phone calls you add Teams Phone and a connection to a carrier, through Microsoft Calling Plans, Operator Connect or Direct Routing. Together, that is a UCaaS set-up.
What happens to UCaaS if the internet goes down?
Calls can be diverted to mobiles automatically, and staff can keep working from the mobile app over 4G or 5G. Many businesses also add a backup connection so the office stays reachable.
Related terms
- Cloud PBX
A cloud PBX is a business phone system run by a provider in its data centres. Extensions, IVR menus, queues and call routing are managed from a web portal, with no PBX hardware on site.
- CPaaS
CPaaS (communications platform as a service) is a cloud service that provides communication building blocks, such as voice calls, SMS, WhatsApp, video and phone numbers, as APIs that developers embed in their own applications.
- CCaaS
CCaaS (contact centre as a service) is cloud-hosted contact centre software. It receives calls, emails and messages, routes them to agents, manages queues and gives supervisors live dashboards and reports, on a per-agent subscription.
- Softphone
A softphone is a phone application that runs on a computer or smartphone. It replaces the desk phone and connects to the company phone system over VoIP, using the business number.
- PBX
A PBX (private branch exchange) is a business's own telephone switch. It connects internal extensions to each other and to the public network, and runs features such as IVR menus, queues and voicemail.
- VoIP
VoIP (voice over internet protocol) carries phone calls as packets of data over an IP network, such as the internet or an office LAN, instead of over the copper lines of the traditional phone network.
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