Dave Michels
Dave Michels is a Principal Analyst at TalkingPointz. His unique perspective on unified communications comes from a career involving telecommunications...
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Dave Michels | November 17, 2015 |


The PBX Is Back

The PBX Is Back Who needs "UC" when you can get a PBX that is software-based, ready to integrate, multimodal, and available as a product or a service?

Who needs "UC" when you can get a PBX that is software-based, ready to integrate, multimodal, and available as a product or a service?

I've never liked the term "unified communications." I've written and spoken about this many times, like in this post from 2010. I prefer "PBX," a term, unfortunately, that frequently gets a negative visceral reaction. However, the term makes sense, and seems to be on the rise once again.

Our PBX Past
I admit that the term PBX is pretty dumb, but I didn't coin it. It stands for private branch exchange, and it goes way back -- introduced as a pull-cord switchboard probably in the '40s. If you watch "Mad Men," you may recall seeing some episodes that show switchboard girls manning the PBX.


As with most technologies, the PBX evolved. It first became mechanical, with pins, rods, and gears to eliminate the pull cords. Then the microprocessor allowed the technology to go digital. Right around the turn of the millennium, the PBX went IP, or more specifically, voice over IP -- though to me it felt redundant to replace "digital" with "IP," since IP is a digital technology.

There's a popular notion that PBX evolution stopped with VoIP, necessitating development of something new, a la unified communications. Although UC does everything the PBX did before it, the term was meant to imply more than a PBX -- much more, such as unified messaging instead of voicemail, support of SIP trunks instead of PRI/TDM trunks, and pop-up call info instead of CTI.

UC's killer app was instant messaging, which enterprise users already well understood thanks to consumer-oriented IM solutions from AOL and many others. All of these new features made it confusing if someone was talking about a super-wonder PBX or a voice-only TDM PBX. UC was an easy solution, as in: "The PBX is dead; time to buy a UC solution."

Everyone went along with the renaming -- the vendors sold UC, customers bought UC, and pundits like me explained UC. But the term itself has always been a misnomer. It has no more unified communications than did the PC make computing personal. UC has just been a convenient label to describe modern enterprise communications.

UC Isn't Everything
Here we are again, but now the evolution of UC is in question.

UC did unify a few aspects of communications, but nothing like Microsoft Outlook or even the smartphone did (neither of which are considered UC). In fact, the average enterprise employee has far more inboxes and communications tools today than in the pre-"unified" era. This is in part because communication modalities evolve more quickly than enterprise systems. Unified messaging, for example, made sense because it unified voicemails with emails, but then messaging expanded to include SMS, over-the-top apps, and social network inboxes.

Today UC is accepted to generally describe modern business communications that likely include:

  • APIs
  • Instant messaging and presence
  • Mobility
  • Telephony
  • Unified messaging
  • Video (sometimes)

But when we look at the situation today, a name change doesn't seem necessary. The PBX had already nailed telephony and voicemail, so it had to be other functions that forced the change.

Mobility? Everything has a mobile app. We didn't change CRM to "unified CRM" with the introduction of mobile clients. A mobile app is a fact of life -- even the Apple iPhone is still a phone. The concept of mobility is very important, but gets captured with terms like "mobile first," "thin client," or even just "app." There is no reason to change the term PBX for the sake of mobility.

APIs? These are important, but to some degree, the same can be said of APIs as mobility -- nothing unusual here. However, the bigger picture might suggest the UC communications-enabled business process story to be a failure. While every UC vendor has pushed APIs and SDKs, Twilio has become a billion-dollar company. APIs are here to stay, but "integrated" communications makes more sense than unified communications. "PBX APIs" also works.

As for IM, which had been a significant new capability, it seems we hit peak usage -- at least from a UC perspective. Various forms of messaging are more important than ever, but people like to IM outside their organizations. UC solutions are well suited for intra-company communications. This is one reason why inter-organizational messaging solutions such as Facebook, Google Hangouts, Slack, Skype, WhatsApp, and even Twitter are growing in popularity.

UC and video have a very tight relationship, at least on paper. Video interoperability is inexplicably easier than IM/p, yet it is common to still use separate video products and services. If you choose to use video in a UC client, that's fine too -- but then you can do so with a PBX client just as easily.

Long Live the PBX
Now let's look at some of the recent innovations in UC: contact center, wideband audio, improved conferencing solutions, cloud-delivered services, and many other mostly voice-related technologies. Can you name a recent major upgrade to UC-powered IM?

UC is really just a PBX. It evolved a bit since we renamed it in 2000, but nothing like the jump from pull cord to mechanical. The PBX is now software-based, ready to integrate, multimodal, and available as a product or a service.

The analysts won't care either way. They never stopped counting voice ports to measure market share.

Enterprises should still replace old PBXs, but with modern PBX solutions, either onsite or hosted. Where to get one? Just search for "PBX." Here is what I found:

  • 8x8: "A virtual PBX is the modern alternative to costly, clunky PBX equipment."
  • Microsoft recently introduced a Cloud PBX capability for Skype for Business.
  • Mitel offers PBX solutions.
  • NEC: Has Univerge 3C, which "delivers a fully functional IP-PBX."
  • RingCentral Office is a "virtual PBX."
  • ShoreTel promises the "easiest IP PBX phone system."

I understand that language changes. I am OK with texting someone instead of sending a text message. I'm even OK with changing "telephones" to "endpoints," even though they basically look and act the same. But it's time to upgrade "UC" back to "PBX."

To be clear, I am not saying UC is dead. I am saying it was an illusion. The PBX is alive, well, and evolving.

Dave Michels is Contributing Editor and Analyst at TalkingPointz.

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