If you offer hosted PBX or UCaaS services from your Metaswitch deployment, then you’re likely familiar with MaX UC. This is the software phone client developed by Metaswitch for business users, and it has some nice features:
- Mobile and Desktop versions
- Contact lists automatically pulled from the directory of business group phone users.
- Presence information for other members of the business group.
- Instant messaging inside the business group, and SMS to external contacts.
- Integration with MaX Meeting (based on Zoom) so you can easily jump into video calls with your coworkers.
However, MaX UC is not the only option for a phone client on the Metaswitch, and we’ve recently spent some time exploring the alternatives.
Technology / Interop Overview
As a starting point, it’s helpful to understand how the key features of MaX UC work, which will help us understand how a third-party client could provide these features for Metaswitch subscribers.
- Voice Calling: Not surprisingly, voice functionality is provided using SIP, according to industry standard RFCs, so any SIP client should be able to register to the Metaswitch and make phone calls. This is the easiest piece of the puzzle.
- Provisioning: MaX UC and physical phones are usually provisioned through Metaswitch Endpoint Packs, which create a configuration file that the client downloads via HTTPS. This isn’t necessary for the clients to work, but as long as the client supports provisioning URLs, it should be possible to create endpoint packs for this purpose (we’ve done it before).
- Directory, presence and IM: On MaX UC this is all provided using the XMPP protocol, with the Metaswitch AMS (Advanced Messaging Server) as the central server providing all the data. XMPP is a standard that other clients could support (and we know people who’ve successfully connected other apps to AMS using XMPP), so that’s one option if you have an AMS server available. Alternatively, some business users might prefer their contact lists to come from another source – e.g. their corporate Office 365 directory – rather than the Metaswitch business group, and some applications support these kind of integrations.
- SMS/MMS: MaX UC supports SMS (not MMS) by connecting the AMS server to an SMSC from a provider such as Bandwidth. Another option might be for an application to integrate directly (perhaps with some middleware) with the APIs provided by Bandwidth / Sinch (or whoever provides your carrier messaging). One benefit of this approach is that it would likely support MMS as well as SMS.
As you look at this list, hopefully you’ll see that it’s not that easy to simply switch MaX UC out for another client. Back when phone software simply made calls, then any SIP client would do, but it’s more complicated now that we need to provide a more holistic communications experience.
MaX UC replacement options
If you only want SIP voice functionality, then any SIP client can register with your Metaswitch CFS through the Perimeta SBC – however if business subscribers are accustomed to the advanced features of MaX UC, you’re likely to need more power than that.
We have not yet performed an exhaustive evaluation of the options, but we have identified a couple of products that we plan to evaluate further.
Acrobits Cloud Softphone
Background: Acrobits is a European company that has been around since 2008, and in 2019 it was acquired by Voyant (later acquired by Inteliquent in 2020, which in turn was acquired by Sinch in 2021). Acrobits has an independent brand, but is labelled as “a Sinch company”.
Product: The Acrobits Cloud Softphone can be highly customized depending on your use case, and you can created branded versions of both desktop and mobile apps. A few features of note:
- It’s possible to create a separate tab on the app for CommPortal, so users can easily access their online phone settings.
- Contacts integration is supported via a variety of methods, including Office 365.
- Messaging is via SIP SIMPLE, and supports both SMS and MMS.
- The application supports Busy Lamp Field functionality via SIP, so even if you don’t have full presence you could fairly easily implement basic line monitoring using SIP.
CounterPath Bria
Background: CounterPath is the company behind Bria and also X-Lite, which was my preferred app for testing back in the day (almost 20 years ago!) when I first started working in VoIP. In 2021 CounterPath was acquired by Alianza for $25M.
Product: There are three versions of Bria, one for individuals, one for SMBs (Bria Teams) and finally Bria Enterprise. It’s only the enterprise version that supports presence and SMS, so most likely that’s what would be needed to most closely match the MaX UC experience.
Update: September 2024
A group of service providers joined our Evaluation Insiders program back in April to sponsor an in-depth assessment of the various clients that could potentially replace MaX UC. Over the course of several months we tested both Bria and Acrobits products, along with applications from Zoiper and Linphone.
Following our testing we have concluded that both the Acrobits Cloud Softphone and the Alianza Bria Enterprise client are viable alternatives to MaX UC, although neither is an exact functional replacement.
If you’re a service provider and would like more information on our assessment, please complete our contact form and we can send you some information on how to purchase our report. If you would like an introduction to either Alianza or Acrobits we would be happy to connect you – again please fill out our contact form and we can touch base before connecting you with the right contact.
