Cloud PBX providers have a number of advantages over other voice-over-Internet Protocol (VoIP) telephony providers that set them apart from the competition.

To appreciate why, users need to go back seven years to understand the origin and current make-up of the VoIP landscape, and how it became a viable industry in the first place, says George Golding, MD of Euphoria.
The VoIP landscape
Since February 2004, network providers have been allowed to offer voice “over any protocol”, thanks to enabling legislation of the time.
The curious phrase used in this seminal law was code for VoIP, a way of sending voice communication over IP networks – which had until then only been used for computer data transmission, such as e-mail.
In the ensuing years, a number of difficulties were overcome by VoIP providers, allowing them to carve out a space in the market.
Most importantly, quality issues were addressed with a variety of techniques. Virtual private network (VPN) connections, backup lines, compression and so forth are all techniques of ensuring quality and reliability and enabling enough concurrent call connections to make VoIP a viable proposition.
Further problems included establishing dedicated national VoIP networks, allocating VoIP-specific 087 numbers, and inking "interconnect agreements" that allow VoIP providers to pass traffic between them without expensive detours.
Many VoIP providers use a PBX (call processing engine) called Asterisk, and add functional components like telephone management, contact centres or collaboration to it.
But that’s where the similarity ends. Providers differ considerably in the way they deliver telephony to clients:
* On-site PBXes – most installations are in the form of server boxes on-site with enterprise customers.
* Skype offers PC telephony in the form of a computer application – consumers call one another from their PCs over the Internet. This service does not offer business PBX functionality and quality is uncertain, and therefore not suitable for businesses.
* Cloud providers – lately, an improvement in South Africa’s bandwidth situation has allowed providers to offer hosted ("cloud-delivered") PBX functionality to enterprise customers.
Cloud versus the rest
Cloud PBXes have much to commend them over other VoIP solutions. A cloud PBX is much more cost-effective than an on-site PBX.
On-site PBXes are acquired, installed and supported at high cost. Cloud PBXes are a low-cost hosted telco service that doesn’t require upfront capital and training/installation cost, and it offers upgrade assurance. Think about it – one PBX can serve a retailer with a 100 branches, compared to on-site installation of 100 PBXes.
Skype is a consumer application that establishes ad-hoc peer-to-peer connections over the Internet, thus sacrificing call quality for low cost. Cloud telephony offers the quality of a dedicated link and an enterprise-grade, managed and supported service.
Beware – some VoIP providers advertise a managed, supported service. But does it combine cost-effectiveness with quality?
Ultimately, the choice of VoIP provider comes down to a good balance between features, quality, reliability and cost-effectiveness:   
* Ask if their network is dedicated to VoIP traffic.
* Compare prices, specifically for international calls. The best VoIP providers offer exceptional quality at very low cost (cheaper than a local landline call), which may suit a business that deals with offshore companies.
* Inspect their service-level terms.
* Inspect their measures to guarantee quality and reliability (dedicated network, compression, technology backup and redundancy).
* Do they have a telephone management system offering instant real-time call reporting? This offers amazing control over expenses compared to having multiple Telkom bills in hard copy for every branch.
* Does the provider offer custom caller IDs for mobile sip clients? This allows the workforce to maintain their caller ID as their mobile number for inbound calls, while making calls over WiFi and 3G through the cloud PBX.
* Does it offer pure per-second billing? It’s absolutely essential for substantial quick-win cost savings.
* The provider must also offer tight security in the form of 256-bit encryption, closed networks, credit limits and strong password management, to protect against intrusions and account abuse. If an account is breached, it could cost a business tens of thousands in call costs by unauthorised users.