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Migrating from PBX to VoIP: A hybrid VoIP approach

A hybrid VoIP system can be the bridge from PBX to VoIP telephony strategies. Our expert helps to highlight the advantages of a hybrid approach.

Of the many evolutions and revolutions we've witnessed in IT in recent years, none has been as long and drawn out as the migration from traditional, PBX-based telephony to digital voice over IP.

Two factors influence the lengthy transition from PBX to VoIP. First is the importance of analog voice to business and, in the early days of VoIP, legitimate concerns about the suitability of internet-based VoIP for business use. In the past, VoIP suffered from issues with reliability and lack of bandwidth -- factors that led to quality issues.

The second factor had to do with the nature of PBX deployments themselves. Although they were often complex and expensive to install, PBXs were highly reliable. Because analog telephony was so well established, the traditional PBX could do its job and remain in place a lot longer than many other elements of the IT infrastructure.

Today, VoIP is considered business-class, with many of its voice-quality issues addressed. Unified communications as a service (UCaaS) can provide telephony and other messaging-related features without requiring Capex for on-premises gear or the ongoing maintenance required by traditional PBX and telephony platforms. Except for some very specialized companies, migrating from PBX to VoIP is on the strategic roadmap somewhere. And that means hybrid VoIP is something that must be considered.

What is hybrid VoIP?

So, what is hybrid VoIP? Functionally, it bridges the gap between the traditional analog world and VoIP. Hybrid VoIP assumes a traditional analog system as the foundation, to which VoIP capability is added.

To do that, a Session Initiation Protocol (SIP) gateway is deployed to provide the interface into packet-based VoIP. Depending on the vendor, the SIP gateway service could consist of additional cloud-based functionality.

The packaging and name of the hybrid component will vary by vendor, because traditional PBXs are built around proprietary hardware. But the core SIP functionality is standards-based and will provide connectivity to SIP endpoints. With hybrid VoIP in place, your existing analog users would be able to use their existing handsets and place calls over IP -- in addition to whatever existing analog connectivity they have. This makes the eventual transition from PBX to VoIP simpler.

Does hybrid VoIP fit your telephony strategy?

Now that you know what hybrid VoIP is, how do you decide if it's right for your company?

First, you need to define your ultimate goal. Do you want to supplement and enhance your existing analog environment, or are you looking forward to the day you can power down your on-premises PBX hardware and be completely UCaaS?

If you asked a UCaaS vendor, its reps would likely laugh and say, "Why wait? Do it today." But as good as UCaaS might be, cloud-based platforms simply don't offer the same scope of telephony functionality that analog platforms provide. So, it's worth taking time to research the path from PBX to VoIP.

Earlier this year, The Tolly Group compared several services and identified more than 100 different call-related features offered by a traditional, analog telephony platform. Analog platforms provided more features and subfeatures compared with those offered by UCaaS competitors.

Sure, traditional telephony and UCaaS platforms will both have core features. Call transfer? Check. But what about the different types of call transfer? Do you need more advanced call transfer features, such as blind, consultative, intercom, mailbox or whisper? If not, hybrid VoIP is likely your best path to the cloud. If you require these more exotic call transfer features, hybrid VoIP might be something you consider down the road as a more long-term expansion to your existing system.

If all you require is basic telephony, then hybrid VoIP is your steppingstone to UCaaS. By implementing hybrid VoIP, you can get the flexibility and cost savings of UCaaS while planning a controlled migration from your existing analog PBX. When it makes financial sense to phase out your analog gear, you can migrate fully to the cloud. For basic telephony needs at new, greenfield sites, you can skip hybrid VoIP and move right to UCaaS.

Be forewarned, though. Hybrid VoIP is anathema to UCaaS vendors. Hybrid VoIP is territory owned by traditional telephony vendors, such as Avaya and Mitel, so customers embracing hybrid VoIP are customers the UCaaS vendors can't have. And when those customers do decide to embrace the cloud, it will be much easier for them to migrate to cloud offerings marketed by traditional analog vendors.

Vendors have a vested interest in whether you embrace hybrid VoIP or not. Traditional analog vendors will be all for it, while UCaaS vendors will be against it. Do the right thing and consider your company's needs before considering the needs of your telephony vendor.

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