What is Call Manager Express?

We’ve all heard of Cisco Unified Call Manager (CUCM). It’s that big monolithic Cisco app used to manage telephony systems in enterprise environments. But have you heard about its little brother, Call Manager Express? Today, we’re going to introduce you to Call Manager Express, explain how it’s different then CUCM, and why Call Manager Express might be used instead of CUCM. 

And, if you’re looking for a quick Call Manager Express primer, check out CBT Nuggets trainer Lalo Nunez’s Cisco CME Configuration training.

An Overview of Call Manager Express

In this video, CBT Nuggets trainer Lalo Nunez explains what Call Manager Express is and its role in enterprise settings.

How is Call Manager Express different from CUCM?

CUCM is a large application that manages telephony systems in enterprise environments. It does everything from managing call plans to handling features like voicemail or parked calls and call routing. Likewise, CUCM can manage telephony systems across remote branches, too. 

Call Manager Express is very similar. It also manages features like call plans and parked calls. However, Call Manager Express runs within the local router instead of in its own node in the core network. For this article, that’s the biggest difference between CUCM and Call Manager Express. 

Of course, that comes with its own limitations. While Call Manager Express offers many of the same features as CUCM, its supported feature set is still limited in comparison. Likewise, Call Manager Express only manages local telephony services. It can’t manage phones at remote branches. Another big difference is that most versions of Call Manager Express are administrated through the CLI, while CUCM is managed through a GUI.

Why use Call Manager Express Instead of CUCM?

CUCM is an excellent option for a centralized telephony management platform, but it isn’t always the best option. It requires additional components, and if your organization is managing remote locations, those remote branches need stable communication back to the core branch via Layer 3. Otherwise, telephony services at those remote branches won’t work. 

That’s a primary use case for using Call Manager Express. Call Manager Express operates within the local router. So, if the router can connect to the PSTN, Call Manager Express and local telephony services will continue to operate despite connectivity back to headquarters. 

Another reason to use Call Manager Express is to decouple the administration layer. For example, some organizations may have multiple remote locations without a primary headquarters. Otherwise, each branch location operates as its own business. It doesn’t make sense to use CUCM in this case. 

Here’s a good example. Let’s say you are a freelance IT administrator, and a fire company or car dealership contracted your services. In both instances, there could be a primary headquarters (city government or a primary dealership location), but that’s not typically the case. Even though firefighters are tax and donation funded, they operate outside of the realm of local government. Likewise, a car dealership with multiple branches is more likely to use cloud services to sync information without a centralized core network. 

Call Manager Express is a perfect use case in both scenarios. Telephony services would be managed and operated at the local offices only. Because there isn’t a core network or management platform, keeping services segregated from other firehouses or car dealerships makes sense. 

Does Call Manager Express Offer Fail-over Services?

Wouldn’t it be nice if your remote branches had an easy telephony fail-over solution? After all, you don’t want call services going down if someone happens to chop the fiber connection to the core network. In a CUCM-only installation, if the core network at headquarters fails, all remote branches bite the dust, too. No one will be ordering pizza for lunch. 

Call Manager Express interoperates with CUCM, however. Remote branches can utilize CUCM as its primary provider, but if communication fails over the WAN, remote branches can fail over to Call Manager Express locally. So it won’t matter if the construction company rebuilding the C-suite offices manages to chop the trenched fiber line with a backhoe. Those remote branches will still be able to order pizza. 

As for that fiber line, there are more likely reasons that WAN connectivity will fail. That’s only a personal nightmare I’ll never let go of. The takeaway here is that Call Manager Express is an easy solution to provide fail-over telephony services in remote locations. 

Starting Leveraging Call Manager Express

By now, you should be biting at the bit to learn more about Call Manager Express. It’s a highly versatile option all network engineers need to keep in their back pockets. Now is the perfect time to learn how to use it, too. Sign up for a free week at CBT Nuggets and start watching Lalo Nunez’s Cisco CME Configuration online training. You can complete the course in a weekend and have a solid foundation to build on!