According to Merriam-Webster dictionary, integrating is "to form, coordinate, blend into a functioning or unified whole." However, the definition does not imply or promise that creating a "unified whole" is better, easier to use, saves money or makes anyone more productive.
When it comes to unified communications, integration has no intrinsic value.
Presence status = Busy (Slightly queasy thinking about bacon and candy canes)
In the culinary world, "fusion cusine" combines elements of various culinary traditions while not fitting specifically into any. And yet in my own kitchen, if I choose to combine (aka integrate) soy sauce, horseradish, peanut butter and tuna, while I clearly have fusion, I most definitely do not have something good! (Try it, you won't like it!)
In a similar fashion, in the UC world, integrating various offerings, in and of itself, does not necessarily provide any value. You win no "brownie" points just because you technically integrated two systems.
This is not to say that integration never provides value; however, the effort and trouble of integration should be aligned with specific business requirements.
Combining for the sake of combining, simply because it can be done, or to prove it technically can be done, is not a sufficient reason to do so.
Click to call is an example of something that is often combined "just because". It is certainly nice to be able to click a name or a phone number on your desktop computer and be able to communicate with that person, be it via instant messaging, voice or video.
However, if you happen to be using for example Microsoft Office Communicator (or if you are an early adopter then say Microsoft Lync) and you happen to have Cisco or Avaya VOIP, the integration and support pain needed to make click to call (via remote call control, aka RCC) is likely not worth the effort.
Unless there is a clear, defined, quantified business benefit associated with click to call, in a multi-vendor environment trying to enable this feature is likely not worth the cost or pain!
Integrating communication solutions from multiple vendors is hard! It is often only supported by one of the two vendors – which is a difficult spot to be in when a problem occurs – and in multi-vendor integrations you can be sure problems will occur! If problems don't occur right away they are likely to appear when either platform involved in the integration is upgraded or patched.
Similarly, supporting rich "telephony" presence, whereby your presence status changes to "in a call" when you pickup your handset, is very nice. However, this functionality is also likely not worth the investment of time and cost if you are trying to do this using components from more than one vendor.
If you have Cisco telephony and have or plan to deploy Cisco Unified Personal Communicator (CUPC) on the desktop to support IM, rich presence and click to communicate then great. Cisco will stand behind any problems you have.
If you have Microsoft OCS or Lync on the desktop and plan to use Microsoft to provide voice services then great. Microsoft will stand behind any problems you have.
If you have Avaya telephony (which includes historical Nortel telephony) and are happy to use the Avaya One-X Communicator on the desktop then great. Avaya will stand behind any problems you have.
Choosing a single vendor makes integrating different communication services a reasonable and supported approach.
If however, you have multiple communication vendors, I would urge you to think long and hard before deciding to integrate services across these platforms.
Of course, things are not always complicated.
Some integrations, for example using one vendor for voice mail and a different for telephony, have better defined boundaries and as such are not as "messy" and troublesome. Using Avaya Modular Messaging along with Cisco VOIP or using Microsoft Exchange Unified Messaging with Avaya or Cisco VOIP generally work well – and interestingly enough are supported by both vendors!
Similarly, call recording solutions (such as NICE) play well with Cisco and other VOIP solutions. These solutions were naturally designed to work well together and the two vendors are cooperating rather than competing.
It should be clear to all that the four communication giants, Cisco, Microsoft, Avaya and Research in Motion all want to control all forms of communication in an organization: voice, voice mail, email, instant messaging, presence, audio conferencing, video conferencing, web conferencing, mobile functionality. The giants may partner, in the short-term, to address gaps in their own product line but the clear long-term goal is for each to be able to provide a complete communication solution by themselves without the involvement of the other three. You may be able to control one giant but I would argue two giants is a lot for any of us to wrestle with.
If you are asked to integrate components from the four communication giants or other directly competing companies, make sure there is a real reason to undertake this integration. Push back on the business users: Is it really that hard to dial a phone number? How important is it that your presence status changes automatically when you pick up the phone? Would you be willing to have users manually change their presence status when they started a call?
Presence status = Available (hungry again but this time thinking about a hamburger and fries; now that's a worthwhile combination!)
Have you successfully integrated communication solutions from multiple vendors? What was your experience like? (Did the recipe taste good in the end?)