Integrated Messaging vs. Unified Messaging


HaileyI’ve read a number of threads about this topic online and am surprised to see that a lot of folks only tend to focus on the technical differences between Integrated Messaging and Unified Messaging.  I find this funny simply because there’s not much debate there…they are what they are.  I think you have to look deeper than that to figure out what you or your clients need, want, and/or are even capable of supporting.  So, let’s get the obvious out of the way.  What is the technical difference between Integrated Messaging and Unified Messaging?  In the most simplistic terms, there are really 2 key differences and they are the Message Store and the Email Inbox. 

With Unified Messaging, there is a single message store where all messages (voice and email) are stored.  For example, Microsoft Exchange.  In turn, there is a single Email Inbox where all email, voicemail, and even fax messages are received.  For example, the Microsoft Outlook “Inbox”.

With Integrated Messaging, voicemail and email is stored separately.  For example, email is stored in Microsoft Exchange.  Voicemail is stored separately on Unity Connection.  In turn, there are separate inbox folders for email and voice messages.  For example, email will be in the “Inbox” of your Microsoft Outlook.  Voicemail may be seen in Outlook too but it will be in a separate folder created when you configure an IMAP account in Outlook that points to the Unity Connection server.

So what kinds of things do we need to consider here to make the right decision? 

1.      Do you want voicemail to be received in your email inbox?

2.      In a UM deployment, you need to consider not only the additional storage space that may be needed for the mailstore to support what is essentially just more email, but also the additional impact this will have on transaction logging (ex:  increase in number of messages received and subsequently deleted in a given timeframe).  This is not always easy to calculate.  In a migration scenario, you need data from the legacy voicemail system to calculate what the amount of voicemail traffic may shape up to be.  It’s also been my experience that once the UM solution catches on, the use of voicemail (intra-company) typically goes down but the use of email equally goes up (if I know my voicemail is going to your email, I’ll just email you anyway).

3.      Do the AD/Exchange and Voice teams interact with each other well or are they separate groups with separate agendas and priorities?  If so, this can cause a problem (in general) but specifically in a UM deployment because, in the case of Cisco Unity, the application is tightly integrated with AD/Exchange.  Not every Voice engineer grasps the concepts of LDAP and email just as I’m sure that not every AD/Exchange engineer grasps the concepts of call routing, dial plan, and so forth.  When there is a problem, you may be completely reliant on the other group to help you out.  However; in an Integrated Messaging environment, the Voice team may have more control over the solution (i.e., it’s now a voice application).

4.      Are you moving away from a Windows-based server environment and towards an appliance model?  If so, Unity Connection and Integrated Messaging may be the right choice for you.  On the other hand, are you moving towards virtualization of applications?  Unity 7x supports VMWare for production use.

5.      Are there regulatory factors regarding storage of electronic records that may come into play for your organization?  With UM, technically everything is email.  What sorts of storage and retention policies are being placed on email, voicemail, and so forth?  Do those policies change once everything is stored in the same place?  I’ve consulted with clients that had to really think about these sorts of things.  They usually give some serious consideration to Unity Connection.

So, which is better?  You tell me.  This is intended to get you thinking…not to outline every consideration that needs to be made.  My main point here is that simply trying to answer which is right for you based solely on end user experience might, in some cases, be short-sighted.  Sometimes it’s as simple as “I want UM” but often not.  In other cases, what a customer thinks they want turns out to be exactly what they don’t want…how do you find out?  You have to ask them the right questions and you may have to play Devil’s Advocate for a bit which means you need to think about things from a number of angles.

One response to “Integrated Messaging vs. Unified Messaging

  1. Couldn’t have explained it better myself. Simple, easy to understand the differences and what makes it different.

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Nick Kelly

Cybersecurity Engineer, Cisco

Nick has over 20 years of experience in Security Operations and Security Sales. He is an avid student of cybersecurity and regularly engages with the Infosec community at events like BSides, RVASec, Derbycon and more. The son of an FBI forensics director, Nick holds a B.S. in Criminal Justice and is one of Cisco’s Fire Jumper Elite members. When he’s not working, he writes cyberpunk and punches aliens on his Playstation.


Virgilio “BONG” dela Cruz Jr.

CCDP, CCNA V, CCNP, Cisco IPS Express Security for AM/EE
Field Solutions Architect, Tech Data

Virgilio “Bong” has sixteen years of professional experience in IT industry from academe, technical and customer support, pre-sales, post sales, project management, training and enablement. He has worked in Cisco Technical Assistance Center (TAC) as a member of the WAN and LAN Switching team. Bong now works for Tech Data as the Field Solutions Architect with a focus on Cisco Security and holds a few Cisco certifications including Fire Jumper Elite.


John Cavanaugh

CCIE #1066, CCDE #20070002, CCAr
Chief Technology Officer, Practice Lead Security Services, NetCraftsmen

John is our CTO and the practice lead for a talented team of consultants focused on designing and delivering scalable and secure infrastructure solutions to customers across multiple industry verticals and technologies. Previously he has held several positions including Executive Director/Chief Architect for Global Network Services at JPMorgan Chase. In that capacity, he led a team managing network architecture and services.  Prior to his role at JPMorgan Chase, John was a Distinguished Engineer at Cisco working across a number of verticals including Higher Education, Finance, Retail, Government, and Health Care.

He is an expert in working with groups to identify business needs, and align technology strategies to enable business strategies, building in agility and scalability to allow for future changes. John is experienced in the architecture and design of highly available, secure, network infrastructure and data centers, and has worked on projects worldwide. He has worked in both the business and regulatory environments for the design and deployment of complex IT infrastructures.