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Top 5 considerations when moving multi-vendor and legacy PBXs to Cloud Phone System

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Top 5 considerations when moving multi-vendor and legacy PBXs to Cloud Phone System

Written by Modality Newsroom on 27, June 2017

Head of Pre Sales Peter Vasey shares his view of the top 5 considerations your business should be aware of when moving multi-vendor and legacy PBX systems to Microsoft Cloud Phone System (previously Cloud PBX).

Peter Vasey, Head of Pre Sales, Modality Systems

[Note: This blog was updated in February 2019]

I’ve been asked recently what I would list as my top considerations for businesses, when faced with moving multi-vendor and legacy PBXs to Cloud Phone System.

As far as questions go, it is fair to say this one is quite specific, but I am not one to turn away from a question. So here goes; my view of the top 5 considerations you should be aware of when dealing with multi-vendor and legacy PBX systems.


1. Know your current telephony infrastructure

Many clients want to detail everything about their current PBX, and while that is good, the key things that you need to communicate to your partner are detailed below. A lot of the other information is superfluous but not necessarily irrelevant:

  • Where your PSTN ingress and egress points are
  • How many PSTN channels there are
  • What type of PSTN connectivity is presented (analogue/ISDN2, ISDN30e or SIP)
  • If it is ISDN30e, how many channels are active
  • What, if any high availability and disaster recovery services are included


2. Know how your users communicate, who they communicate with and what functions they use

This is massively important and you may be surprised at how your users work, it may not be what you think. Make sure you go through an exercise of profiling your users so you have a clear view of how they work now and so you can prepare them for new ways of working. This step is often missed and assumptions are made that users will just ‘get it’ – sometimes they don’t and that leads to a low take up and adoption.


3. Multi-Vendor thinking

If you have a multi-vendor estate, apply the same logic as in point 1, but make sure you detail any internal routing and any direct SIP trunks between the legacy vendors.


4. Don’t overcomplicate the solution

We see it all the time because ‘that is how the PBX works’: Skype for Business and Cloud Phone System are Unified Communications tools, PSTN services and telephony is a small chunk of what it can do. Many organisations list reams of button functionality, a mandatory desk phone policy and want functions including ring back etc. By profiling your users, you can determine what is a real functional requirement and what is no more than an ‘I want’. Skype for Business does things differently and that is not necessarily a bad thing. Technology and ways of working change. Understand the changes before listing them as must have functions.


5. Know the golden rule: any one user should either use the legacy PBX OR Skype for   Business for their telephony, but never both

This is all about the End User Experience. When you have both a PBX(s) and Skype for Business with Cloud Phone System in your estate, you want to make sure that routing calls between the two environments is possible. You do not want users having calls forked to both the legacy PBX and the Skype for Business solution, this leads to a confused user experience, calls landing on the PBX will be taken out from the Unified Communications platform, and voicemails and notifications will behave differently to those of Skype for Business. Skype for Business calls will have far richer functionality and features. Your users will not thank you for giving them a confused solution and your CFO won’t thank you for having to support two telephony platforms.

A move to Cloud Phone System could be the catalyst for wider business transformation, from reducing costs to allowing your business to grow at a rapid rate.

In an always-on digital age, choosing Cloud Phone System means choosing a more efficient way to work, delivering powerful productivity options and the wider functionality of Skype for your business.

As well as being a reliable, secure solution to transforming your business, Cloud Phone System is also a key communication tool, allowing your business to connect on a much larger scale.


Peter Vasey

Head of Pre Sales | Modality Systems

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