CTI (Computer Telephony Integration) w/ Office Communications Server

Side Note: I know I haven’t blogged much recently, but I’ve changed roles within Microsoft, been on parental leave and busy working with customers. However I am planning a series of post about creating UC solutions..

I get this question a lot, "Does Office Communications Server integrate with CTI?"  The Answer: It depends

Why do I say that? Well when most people ask about CTI, they are typically asking about CSTA applications. IE: ACD, Predictive Dialing, Screen Pops, etc..  And it depends on your OCS implementation.

Remote Call Control

You can run your current CSTA based CTI application in tandem with your OCS environment in a Remote Call Control scenario as your CTI server will sit as a branch off the PBX. However the Remote Call Control scenario has no real interaction between OCS and the CTI server. Therefore you can't call that real integration. Besides the Remote Call Control scenario doesn't utilize the full potential of our UC platform.


Enterprise Voice with PBX Integration

With a OCS deployment with Enterprise Voice, can it support your CSTA based CTI applications? No for the fact that your internal telephones are no longer "directly" linked to the PBX, but instead all telephone calls are routed through your OCS infrastructure.

Does this mean OCS doesn't support CTI applications?

No, it just means that it doesn't support CSTA based CTI applications. CTI doesn't have to be based on CSTA. If you look at what CSTA is, it is essentially a schema. A schema that defines what a telephone call is and from a software developer perspective this is antiquated approach to solving a common problem. Why don't we have predefined schemas for everything, such as customer data, financial transactions etc... ? All business have customers and money changing hands, yet we don't commonly see standardize schemas. Yes having predefined schemas for everything would solve a lot of problems, but businesses are unique. Just because you run a bakery doesn't mean all bakeries care about the same data.

I know it seems like a Microsoft employee bashing "standards" but keep reading.

Let's take "Screen Pops" for example, when a call is transferred from the IVR application to an agent, the agent should get the customer's information from the data the IVR collected. In a traditional CSTA environment the call information and relevant data is written to the CTI server. When the call gets transferred to the agent, the agent has a piece of software sitting on the desktop which either queries or gets notified with the appropriate data from the CTI server.  If you remove the context of the telephone, it simply is a client application that gets notification from a server application that an event has occurred and passes the data to the client.

.NET and/or Java developers create client/server applications every day! As a .NET developer I'd create a WCF service which the IVR application could call and pass in the data it collected, along with the who it is transferring the call to. On the agent's desktop I would have a small application that would register it's endpoint with the service and listen for any events that pertain to it. The client application could even integrate directly with a CRM application, provided that the CRM application has some sort of API.

I know you are probably reading this and wondering what does this have to do with OCS? Well nothing and that's just the point…

In this Screen Pop solution, the actual Screen Pops have nothing to do with OCS. The OCS APIs could be used to create the front end IVR application and provide business logic presence information for agents, so that the IVR knows who to route the call to.  NOT to display Screen Pops. I know what I am saying goes against what others have suggested such as the UC Client API - Screen Pop Sample. It is however just a sample and is only one way to solve a problem. In my opinion creating a custom OCS client to display “Screen Pops”  does "lock" you down to OCS, not to mention the increase investment of time to develop the application.

You shouldn't try and reinvent the wheel using the UC APIs, but use them for something that doesn't already exist. My rule of thumb is that the UC APIs should be used to serve two purposes: 1.) Provide modalities to your applications. IE: Telephony and IM  2.) Provide your application with presence data. 


CSTA defines a "standard" so that you aren't “locked” down to use proprietary extensions. By applying modern SOA techniques to your solution you create a solution that is loosely coupled and could easily be adapted to any other OCS ish products out there and therefore not forever committing you to a single product and/or platform. Believe it or not as a Microsoft employee, I don’t want you to feel that you are “locked” into our products, I want you to buy our products because they are the best in the industry and will give you the greatest return on your investment. 


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