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Moving Skype for Business Voice to the Cloud?

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Moving Skype for Business Voice to the Cloud?

Written by Modality Newsroom on 17, May 2016


Cloud Phone System (formerly known as Cloud PBX) is coming down the track like a freight train; it doesn’t cover all possibilities, but you can certainly look to reduce your on-premises footprint now, whilst planning for the future. Learn more about the Skype for Business Cloud considerations from Head of Pre Sales Peter Vasey.

pete vasey circle

[Note: This blog was updated in January 2019] 

We do a lot with Enterprise Voice in Skype for Business across Office 365, On Premise and Hybrid. Without Enterprise Voice, the architecture and the placement of a Skype for Business solution is pretty straightforward and comes down to cloud strategy more than anything else.

On premise Enterprise Voice is well established, but can you really move all your voice to Cloud Phone System? Well, yes and no… (I am a consultant, so you’re going to get a consultant’s answer!).



What are the different ways you can deploy voice?

1. On Premise Skype for Business

This gives you the full features and functionality of Enterprise Voice and access to APIs to integrate with a contact centre, call recording etc.


2. Skype for Business online

The APIs associated with Skype for Business Server are not accessible in Skype for Business Online. This can lead to functionality gaps or the need to augment some of the more advanced functionality with third party products. Cloud Phone System PSTN services are available in two ways:

A. Through Microsoft provided PSTN and PSTN Conferencing services.

B. Through local breakout for PSTN and conferencing by using the Cloud Connector Edition (CCE), which enables routing to legacy PBXs and allows you to migrate away from traditional telephony.


3. Hybrid

This offers a part on premise and part Office 365 solution giving you the best of both worlds. It also allows a combination of Cloud Phone System and Local PSTN breakout alongside legacy PBX routing.


Is Office 365 ready for Enterprise Voice and PSTN?

Largely yes. The key point here is that (at the time of writing) not all functionality you’d expect is available yet. Response Groups, for example, are on their way but not currently available and if you are planning your solution correctly, if a function is not available you need to plug the gap. The other key area that is being worked on by Microsoft is that of access to the APIs. In fairness to Microsoft, hosting such a complex and large platform does mean that if you want to allow applications to communicate with Office 365, you have to make sure that testing is executed thoroughly. I am strongly with Microsoft on this approach, they need to be 100% certain it is carried out correctly and securely.

In reality, this means that if you have a need for contact centre, call recording or some other kind of application integration (and by this I mean integrating it properly, not like some of the fudges/ workarounds that are available on the market right now) then Office 365 with PSTN or CCE is not going to tick all your boxes - a lot, yes, but not all.

This is where Hybrid comes in to its own. If you already have a Lync 2013 or Skype for Business infrastructure on premises, then consider using it in conjunction with Office 365. Put information workers in Office 365 and leave those who require more complex voice functionality on the on premise infrastructure (or get someone else to host it for you). That way, you can have all the functionality you need for all of your users. This almost always results in a reduced on premise foot print. Microsoft releases more functionality in Office 365, then moves more users over to it. Look at it as a migration strategy, not a sliver bullet… not yet anyway.


What are some of the points to watch out for?

  • Users on Cloud Phone System will have different Conferencing details

Our software development team have created a very nice tool to overcome this issue called CustomInvite.

  • Users in response groups will all need to remain on premises
  • Make sure you understand the licensing models fully

Not many understand the Cloud Phone System licensing models yet and where the PSTN Conferencing/ Cloud Phone System PSTN add on comes in to play when looking at E3/ E5.

  • Don’t be afraid of Hybrid

The technology has been about for quite some time, just treat it as a stage of the migration to Cloud Phone System.

  • Consider contact centres

For those seeking more advanced call distribution functionality, consider the use of a contact centre to plug the gap. Cloud-centric contact centre products are gathering speed, and in some cases licensing models will allow an organisation to manipulate call flow very effectively. This can be delivered through on premises, hybrid or cloud hosted services - this final option is by far the most popular at the moment.

  • Considerations for defining solution SLAs

When defining solution SLAs, remember that Microsoft only offer a 99.9% uptime if you have Cloud Phone System. Even if you define a 99.99% SLA or OLA, you will be subject to the Office 365 SLA.


In summary, Cloud Phone System doesn’t cover all possibilities, but you can certainly look to reduce your on-premises footprint now, whilst planning for the future. 

Skype_for_Business_cloud_PBX_deployment_guide_image.pngFind out more about Skype for Business Cloud Phone System deployment models, and our range of services available to help you in our user-guide





Peter Vasey
Head of Pre-Sales | Modality Systems

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