In the past few years, Microsoft has focused more and more on online and hybrid solutions, so I guess it's only natural that Microsoft Lync Server heads that way as well with its latest release. Lync Server 2013 brings to the table several models for deployment that organizations can take advantage of:

  • Lync on-premises—In this method, all servers are installed and maintained onsite by your organization. An on-premises deployment provides all of Lync's rich features: IM\presence, conferencing, and Enterprise Voice.
  • Lync Online—This deployment method relies solely on a Lync 2013 cloud services solution such as Lync Online through Microsoft Office 365. Lync services are provided through the cloud, and typically only a subset of Lync features is available.
  • Lync hybrid—This method provides a combination of Lync on-premises and Lync online, with some users hosted in the cloud and others hosted on servers you deploy and maintain. Only users hosted on servers you deploy on premises have a full set of Lync Server features.

Lync Server 2013 has added several new features as well, such as HD with conferencing and more emphasis on group chat. But now let's take a closer look at some of the Lync deployment scenarios to help you choose the right method for your organization.

Lync On-Premises Deployments

Lync Server 2013 on premises is the model with which most of us are familiar in which you deploy your Lync servers onsite in your organization. The servers sit somewhere in your data center, all nice and secure, and you can take a stroll through to see their blinking lights flash so you know everything is working fine, giving you that warm fuzzy feeling. With Lync Server 2013, not a lot has changed with this model; you can still deploy in this method whether you use the Standard or Enterprise edition.

Now, there are some server role changes that have taken place in Lync Server 2013 that make this model still something to strive toward so that you have the total Lync solution. If you're looking at integrating Enterprise Voice with an existing PBX system, Lync Server on premises can be the best choice for a deployment method.

Lync Online Deployments

Microsoft’s Lync Online deployment option is great for simplicity and manageability when considering which type of deployment to consider. Lync Online provides IM\presence, conferencing, and voice (peer to peer) between users in the organization.

Lync Online provides a very similar feature set to Lync on premises. If the concentration of your organization's communications is around IM\presence and making Lync voice calls to each other through your computer, this would make an ideal solution. For small organizations that don't have the skill set or time to get up to speed on server requirements, which server editions to deploy, and so forth, focus on Lync Online.

There are several plans to choose from, such as a basic Lync plan that provides IM, PC-to-PC audio calling between Lync users, and web conferencing. A more advanced plan requires purchasing a calling service from a qualified Office 365 partner for connectivity to the public network and local phone numbers (for incoming and outgoing calls). You can find more information about Lync Online options on Microsoft's Office 365 website.

Lync Hybrid Deployments

A hybrid deployment is a deployment in which some users are homed on-premises and some users are homed online, but they share the same domain. Now the fun begins because the next question that usually comes to mind is: Which modalities or workloads should be where? This question leads me to my next explanation: There are two types of Lync Server 2013 hybrid deployments to be aware of:

  • Hybrid Lync Server—An on-premises Lync server configured for use with Microsoft's Lync Online solution
  • Hybrid voice—An on-premises Lync Enterprise Voice deployment for Lync Online users; this deployment method enables Lync Online users to make and receive calls from on-premises PSTN gateways

There are some requirements to take into consideration with the move to a Lync hybrid deployment. For instance, you'll need to have the following servers installed on premises:

  • An Active Directory Federation Services (ADFS) server running Windows Server 2008 R2 SP1
  • A Microsoft SQL Server instance
  • Lync Server 2013
  • A DirSync Server

You'll also have to meet one or the other of the following topology requirements:

  • Microsoft Office Communications Server (OCS) 2007 R2 with Lync Server 2013 on premises; Lync Server 2013 Edge Server with the next hop being a Lync Server 2013 server
  • Lync Server 2010 with Lync Server 2013 on premises; Lync Server 2010 Edge server with the next hop being a Lync Server 2010 server

You can find additional requirements in the Microsoft TechNet article "Considerations for Lync Server Hybrid Deployments."

Some key considerations for hybrid voice are the Call Park and Response Group applications. These features came out with Lync Server 2010 and have been enhanced for Lync Server 2013. In order to deploy hybrid voice, you'll have to deploy and configure these applications on premises because their functionality applies only to on-premises users. Definitely keep this restriction in mind if you happen to use either of these applications with Lync Server 2010 and you're thinking about moving forward with Lync Server 2013 in a hybrid scenario.

Make the Right Choice

At the end of the day, the type of deployment you choose should be based on your organization's needs. If you're looking for a simple deployment and don't care much about Enterprise Voice or integration into a PBX, then Lync Online might be the best choice. When you're looking for all the rich features of Lync and are looking at replacing your existing PBX, then Lync Server on premises is the way to go. Finally, the hybrid deployment is a good decision when you're looking to make a step toward migrating an existing on-premises deployment to the cloud.