How to Make Microsoft Teams Work With Your Existing Cisco Phone System 

How to Make Microsoft Teams Work With Your Existing Cisco Phone System 

In our last post, we talked about why so many companies are adopting Microsoft Teams and what options are available to add PSTN calling to Microsoft Teams.  Today, let’s dive into more specifics on the Microsoft Direct Routing option.

A large portion of our clients have migrated to Microsoft Teams for more advanced messaging and collaboration capabilities. They often do this just because it’s included in their Microsoft O365 licensing subscription.  After the initial hurdle of helping users adopt this new platform, the next thing to do is get Microsoft Teams to make outside calls.  

Out of the box, Microsoft Teams easily connects users either in direct calls between team members or into internal team meetings.  This usually results in a large decrease of internal calls on the old phone system.  Why use the old phone system when you can connect with a fellow team member at the click of a button? 

And to make it even simpler, Microsoft Teams doesn’t care where that other person is located.  Click a button and you’re connected to your teammate no matter where they’re located or what device they’re using.  It can be an audio or video call, or a multi-person team meeting.  

So great, it works internally.  But how do you make it work for outside calls? 

You don’t want to bounce back and forth between using Microsoft Teams for internal calls and your old phone system for external calls.  

Microsoft Direct Routing

This is where Microsoft Direct Routing comes into play. Direct Routing works like this:   

First, we add a SIP voice gateway on-premise in your data center.  On the external side of the SIP gateway, we configure it to talk to the Microsoft Teams cloud and allow SIP calls to be passed back and forth. 

On the internal side of the SIP gateway, we configure it to talk to your existing phone system.  So when a call comes into your existing phone system that is for a Microsoft Teams user, it gets directed to the SIP gateway and towards the Microsoft Teams cloud. The cloud then directs the call back to the user wherever they may be located. 

It sounds like a lot of back and forth, but happens so quickly that it’s unnoticeable to either person on the call.   

Enabling Direct Routing allows your organization to keep your existing phone numbers and whatever agreement you have with your current carrier. In most cases, it keeps your overall dial-tone costs as competitive as possible, too.  From our perspective, it allows you to maintain maximum control of your dial-plan with the least amount of disruption.   

If you already have a Cisco phone system in place, this is relatively simple to build out and can be completed as a 1-2 day project.  In some cases, the SIP gateways already exist and we can simply add the necessary configuration to those gateways.  In other cases, we recommend a separate Cisco router (or virtual router in a VM) to function as a SIP gateway to keep the overall configuration simple and clean.   

On the Microsoft side, the subscription plan must be enabled for Direct Routing and costs $3-5/user.  

If you’ve already made the jump to Microsoft Teams, we highly recommend you make the additional jump to add Direct Routing. This gives you the full functionality of Microsoft Teams and lets you keep all the advanced functionality of your existing phone system and services. 

Additional Reading 
Microsoft 365 and Office 365: Making a Move to the Cloud
Using Microsoft Teams for Messaging? Consider Adding Voice Calling Too