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Calling All Centrex Users: Your Cloud Solution Is Dead! (Part 2)


In my earlier post and Part 1 of “Calling All Centrex Users: Your Cloud Solution Is Dead,!” I provided a synopsis for the original Centrex and what it was known for (more about reliability than features and functions of the premise-based systems of yesteryear). Centrex and its sister ACD were the original “cloud,” now UCaaS and CaaS respectively. Both yesterday’s and today’s cloud solutions are OPEX models, allowing an ease of migration factor from a financial perspective.

We also covered the various risks associated with staying with the legacy TDM (or some IP) Centrex. We have a customer with a 7,000+ line Centrex with no availability of adding any more end points and is at end of manufacturer support. The vendor providing the system is offering an on-premise managed solution as the replacement.

In this post, we will cover several factors including more robust solutions in today’s IP-centric world, costs involved with a replacement model, time-to-implement factor. In Part 3, I will provide an overall Centrex replacement plan.

One Centrex Example - Genband and Their Options

I had a discussion with Greg Zweig of Genband, since my original post. By end of support I am referring to legacy Centrex based on Nortel DMS technology or AT&T #5ESS technology. Our discussion included:

  • Greg pointed out that Genband has offered an upgrade path for legacy Nortel DMS carriers to a UCaaS solution “under the skin” to its carrier customers selling Centrex and UCaaS solutions, and it is up to the individual carrier to provide that infrastructure and upgrade

  • According to Greg, all legacy digital Nortel end points, including 2000 series, 3000 series and even P sets are fully supported through Genband’s UCaaS solution. That same technology also supports a full IP suite of Genband end points

  • Genband no longer sells or supports legacy DMS Centrex, so if the carrier serving your Centrex has not upgraded to Genband’s current UCaaS platform you are at risk as the customer, i.e., end of support

  • It should be noted that all digital end points have been manufacturer discontinued 36+ months and have no software upgrades since their discontinuance. Any software enhancements or possible software bugs are no longer provided. It is up to the individual carrier to pass on any upgrade costs or maintain legacy Centrex pricing

  • Legacy Centrex pricing, in my experience has been $10-$15 per end point monthly and difficult to maintain such a low price point (UCaaS typically runs $20-$40 per end point monthly depending on the carrier and feature/functionality offered)

  • It is also up to each Centrex provider to offer SLAs, guaranteed up time a.k.a. 99.999%

Genband is just one manufacturer that offers Centrex and UCaaS to carriers. Others include Lucent Technologies, NEC, Ericsson, and BroadSoft (IP) among others.

So What Is An Enterprise User To Do?

First and foremost, do not panic:

  • Realize that there are newer more robust solutions available, some on premise and others in the cloud (now UCaaS – Unified Communications as a Service, or CaaS - Contact Center as a Service). That new UCaaS or new UC solution with all the “bells and whistles” you have dreamed about could be finally here.

  • Determine if your Centrex is served through a Genband IP solution supporting digital end points, Genband Centrex solution, or other manufacturer. Note that digital end points are manufacturer discontinued and, in my opinion, have some level of risk and offer basic digital features and do not offer IP end point features such as Active Directory, and in some cases, Caller ID

  • Plan on a higher cost replacement model. Many legacy Centrex users are currently charging between $10 - $15 per user (non-Contact Center), well below the OPEX cost for a replacement solution

  • Note that the older Centrex is of course, no longer supported and running risk to your environment

  • In return, you will get a fully supported system and a full UC suite of features and functions

  • You can offset these costs with savings derived from key areas including flat-rated domestic long distance, SIP trunking, IP audio conferencing, IP videoconferencing, Contact Center optimization, Contact Center centralization, Customer Loss Avoidance, internal SLAs for abandoned calls, Average Speed of Answer, and other areas

  • Time-To-Implement a Replacement Solution –

  • May not take as long as one would think. Since most UCaaS infrastructures are already built, the time to build a cloud infrastructure, unlike premise, can be half or even less than the time to build a premise-based solution

  • In less than 24 months (from the time of contract execution), we were able to help a client replace a legacy communications solution with a new UCaaS solution with over 5,000 end points

  • We helped another client migrate from an end of support CaaS Contact Center to a new CaaS solution in less than 90 days (again from time of signing the agreement)

  • For any replacement solution, one needs to assume that the current data infrastructure and cabling infrastructure are current for a fully executed IP environment – you will need a QoS-based LAN and WAN for all voice and video communications, and can use CAT5e/6/7 for voice IP end points (in lieu of cabling replacement you can also consider long range switches that capitalize on legacy CAT3 cabling, NVT Phybridge being one example)

  • Build Your Centrex Replacement Plan to UCaaS or a new premise-based solution – for the following reasons

  • Minimize economic loss

  • Manage disruptions to operations

  • Provide an orderly replacement

  • Protect organizational assets

  • Reduce IT exposure

  • Take on the following Centrex Replacement Plan steps necessary for CxO management approval

  • Identify the Centrex “Under The Skin” (if Available) and Determine your level of risk with the current legacy Centrex – for staying with the Centrex and capacities and possible outages due to lack of spare parts, (lack of) knowledge base, and fewer trained technicians

  • Baseline and inventory your current enterprise Centrex and data infrastructure - for possible replacement purposes

  • Review your corporate and IT strategic plans - for possible growth and change and how a replacement to your Centrex could incorporate such updates

  • Develop and execute a Request for Information (RFI) - for budgetary purposes, as needed, for a replacement UCaaS solution or premise-based solution

  • Leverage any capital investment or increase in OPEX with cost-saving and cost-avoidance opportunities to manage cost increases

  • Develop a budget for the project

  • Document and execute on the Centrex Replacement Plan and overall project plan


In Part 3 of this series, I will detail a Centrex replacement plan based on the seven points above. Ask your carrier if your Centrex is legacy digital or IP “under the skin” (you may or may not be able to get this data). If the Centrex serving you is digital, then it is definitely time to look at a replacement IP technology, cloud or premise.

Lastly, have your Centrex costs stayed flat or have they increased pointedly in the last 12-24 months? That could be your clue that an upgrade has taken place.

Ask yourself - does the carrier offer new UCaaS-like UC functionality beyond basic telephony? And if like many of our clients, you are looking to manage your corporate costs - what you currently have at any increased cost may or may not be the best financial solution. Going shopping is always a way to validate if what you have will support where you want to go.

This article was originally published on BCStrategies.


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