There are four primary configuration scenarios available for the Poly Trio which support Microsoft Teams and the ideal option for an organization can depend on several factors. The most important distinction is whether the Trio is deployed standalone as simply a phone or if it is also paired with Visual + or Visual Pro componentry for enabling video conferencing capabilities.
These four scenarios can generally be categorized as:
- Native Mode
- Gateway Mode
- Hybrid Mode
- USB Mode
The first two scenarios are Audio Only where the Trio is deployed as a standalone phone. The second two scenarios are applicable to Video-Enabled deployments of the Trio.
Note that in all but the USB scenario the Trio itself is the registered endpoint and the configuration is performed within the Unified Communications Software (UCS) firmware which runs on the Trio platform. The Trio performs all call control and can be paired to a variety of supported audio and video components, leveraging one or more registration and meeting platforms. Alternatively the USB mode simply turns the Trio into a USB audio device which is then connected to and controlled by a separate video-enabled endpoint like a Microsoft Teams Room.
The configuration steps in each of the following sections assumes that the Trio is in a factory-reset configuration state before starting, so some of these steps may not need to be performed on a currently deployed device.
Native Mode (Audio Only)
The first and newest option available is to simply place the Trio into the Microsoft Teams base profile which will automatically reconfigure the phone to launch and utilize the embedded Microsoft Team Android application designed for Teams-qualified IP phones. This application only provides for audio capabilities with the Trio, so it should only be used with a stand-alone Trio which is used for audio conferencing. (If any video devices are integrated with the Trio then any connected cameras and display monitors will not function in this mode.)
Configuration
Before attempting to use this option the Trio must first be upgraded to at least the 5.9.0 Rev AA firmware release which first introduced this supported capability.
- Open the Settings menu on the Trio and navigate to Advanced > Administration Settings > Network Configuration > Base Profile and then select the Microsoft Teams option. (The default password is ‘456’.) Tap the back arrow and then select Save Config which will immediately reboot the phone.
- After the phone reboots it will display the Microsoft Teams Sign In screen.
A Company Portal screen may be seen while the client software attempts to connect to the Microsoft Teams services. When the Microsoft Sign In screen appears it will provide two different user authentication methods: one option to directly enter the credentials into the phone using the soft keyboard and another to utilize the Web Sign In process to enter the credentials in a web page on another computer.
If it is desired to enter the account credentials directly on the phone then follow this step, otherwise skip to the next step to alternatively use a web browser on another device to enter the account credentials for the phone.
Tap on the username field to bring up the on-screen keyboard and then type in the username for the desired Teams user account (e.g. trio@msteams.net) and select Next.
Enter the password for the provided account name and then select Sign In.
Alternatively this step can be used to sign into the phone by using a web browser on a computer or other mobile device.
Tap the “Sign in from another device” option
From a web browser on another device or computer go to https://microsoft.com/devicelogin and then enter the alphanumeric code currently displayed on the Trio (e.g. e5s7p7alx) in the Enter Code field and then click Next. (As demonstrated in this example the code is not case-sensitive.)
If the Pick an account window appears and the desired account appears in the list then select that account. If not, then select the Use another account option.
If prompted to sign in then enter the username for the desired Teams user account (e.g. trio@msteams.net) and select Next. Then enter the password and select Sign In.
Regardless of which sign-in approach was used the remainder of the process is the same, as are the resulting capabilities and experience. The phone may briefly display the Company Portal page as the Microsoft 365 tenant is located and then the Teams client will appear once completed.
If prompted to select a login account type select Shared. (This is the only mode that will be supported on the Trio, so while Personal can be selected it is not recommended, nor supported.)
Behavior
The Shared option is meant for common area use-cases like conference rooms where only scheduled meetings on the room’s calendar are displayed, along with the dial pad button used to place an outgoing PSTN call. The magnifying glass icon in the upper right corner can also be used to search for other Teams users or devices to place outbound peer calls to.
In the example shown above there are both Teams and Skype for Business scheduled meetings on the Trio’s calendar. Note that the action button on Teams meetings says ‘Join’ while the button on a Skype meeting (denoted by the Skype for Business logo) says ‘Dial’. this is a very important distinction to understand as the Teams client does not have any native support for Skype for Business; it does not speak MS-SIP and cannot talk to a Skype for Business platform. The only way this client can join a Skype meeting is if the meeting organizer is configured for Dial-In Conferencing or is licensed for Audio Conferencing and the meeting invitation includes the necessary PSTN dial-in number(s). Also, the Teams user registered to the Trio must be enabled with Phone Calling using either Direct Routing or with a Microsoft Phone Calling Plan assigned to it. In short, the Trio must be able place an outbound call to the PSTN via Microsoft Teams in order to connect to the Skype meeting via basic audio conferencing.
The Teams presence state for the account can manually be set directly on the phone by tapping the ‘hamburger’ menu in the upper-left corner of the client and selecting the desired presence state.
For comparison the Personal option can be selected during sign in if prompted, but this mode is more resource-intensive and as previous stated is not supported on the current Trio models. This mode is intended for personal handsets like the upcoming Poly CCX devices and will not only show scheduled Meetings, but also provide additional capabilities in the client applicable to individual users like the history of Calls and Voicemail along with Search and Call Park retrieval options. From the Calls screen the Make a Call button can be used to either search for other Teams users or bring up a dial pad to place a PSTN call. The New event button on the Meetings screen allows the user to create a new Teams meeting directly from the phone and then invite other participants.
Gateway Mode (Audio Only)
This configuration uses a single registration into Skype for Business Online which inherently provides a limited set of core functionality into the Microsoft Teams environment. This is provided by way of a SIP to Teams audio gateway which Microsoft has deployed and manages in their cloud. The gateway is not something that devices point to directly as it is more of a set of backend connections between the Skype for Business Online and Microsoft Teams environments, allowing for mainly peer calling and meeting-join capabilities for 3PIP-qualified IP phones like the Polycom VVX, Trio, or other third-party qualified phones. Thus, the simple act of registering the phone to Skype for Business Online provides some inherent connectivity into Microsoft Teams.
Also of importance is where PSTN connectivity comes from. If the environment is currently using Enterprise Voice in Skype for Business then all PBX functionality and PSTN connectivity is retained via the registration to Skype for Business. If (and when) that Enterprise Voice functionality is migrated to Teams, by way of establishing a Direct Route to Teams or utilizing Microsoft Phone Calling Plans, then the Trio (as any 3PIP-qualified phone) will continue to operate the same via the gateway services. Thus, when moving all users in an environment to “Teams Only” mode and also migrating PSTN connectivity directly into Teams there is no impact to these phones which were already functioning; they simply stay in the same configuration and the gateway masks all of those changes.
Be aware that while this functionality does rely on Skype for Business Online it will not initially be impacted by the planned retirement of Skype for Business Online on July 31, 2021 as announced by Microsoft. Microsoft intends to support 3PIP-qualified IP phones via the gateway services for an additional two years, through July 31, 2023 as stated in this FAQ.
Configuration
Before registering the phone the desired user account should be set to Teams Only mode for best functionality. While this is not a requirement to leverage the gateway, but is recommended for proper functionality. If the account is in a different Teams Upgrade mode, like Islands for example, then peer calling behavior may not function correctly.
Open the Microsoft Teams admin center (https://admin.teams.microsoft.com) and in the Users section select the desired account.
Click Edit on the Teams Upgrade section and change Coexistence Mode to Teams only and click Save. (Ignore the setting to ‘Notify the Skype for Business user’ as this only applies to the Microsoft Skype for Business clients and is not relevant for using the account only with a 3PIP-qualified phone.)
- On the Trio access the Settings menu and navigate to Advanced > Administration Settings > Network Configuration > Base Profile and then select the Skype for Business option. (The default password is ‘456’.) Tap the back arrow and then select Save Config which will immediately reboot the phone.
After the phone reboots tap the Sign In button and select the preferred option for registering to Skype for Business Online using the desired user account.
Behavior
When the Trio is registered to an account which is homed in Skype for Business Online it will retain all currently supported Skype capabilities as it is still in the Skype Base Profile. When a specific event occurs (like placing a call from the phone to another user in Teams Only mode) then Skype for Business Online knows to route that call through the gateway services into the Teams environment. Understand that if a phone is registered with an account homed on a Skype for Business Server which is not part of a Hybrid deployment then this will not function as the gateway service is only accessible via Skype for Business Online connectivity.
As pointed out above, this is an Audio Only experience with Microsoft Teams as the gateway only supports audio. Thus, this configuration is also intended specifically for audio-only deployments and should be avoided with video-enabled configurations. (There is a known issue where video sessions can erroneously be established through this gateway when joining a Teams meeting. This may not be resolved by Microsoft as the gateway is essentially in a maintenance mode and will likely not have any future feature development. Microsoft’s focus is the wholesale replacement of devices to new products which will run the native Microsoft Teams client.)
To provide some insight into how the gateway works simply save a Teams meeting invitation in Outlook as an .html file then open it in any text editor or viewer. Search for the text “focus:id” and the following OnlineMeetingConfLink section should be seen.
Note that this looks exactly like a Lync or Skype for Business conference URI, except for the additional teams:2:0!19: string. The Trio does not look at the actual Teams meeting link embedded in the Join Microsoft Teams Meeting link at the top of the invitation, but will identify these invitations as a ‘Skype Meeting’ by recognizing the conference URI embedded in the message as shown above.
A native Teams client would join this meeting using the native Teams meeting URL.
https://teams.microsoft.com/l/meetup-join/19%3ameeting_NQG2ODNzMTItZTU5Yy95ZTFhLWFmYjgtYjk4MjQ1N2Q0ZmY4%40thread.v2/0?context=%7b%22Tid%22%3a%22bc7c5f16-c55e-417d-aac0-ff6bbfc27f76%22%2c%22Oid%22%3a%22aff3cdcc-4551-4de6-8bec-e7f9e07edf61%22%7d
Yet the phone will leverage the ‘legacy’ Skype conference URI in the invitation which looks much different.
conf:sip:jeff@msteams.net;gruu;opaque=app:conf:focus:id:teams:2:0!19: meeting_NQG2ODNzMTItZTU5Yy95ZTFhLWFmYjgtYjk4MjQ1N2Q0ZmY4-thread.v2! aff3cdcc45514de68bece7f9e07edf61!bc7c5f16c55e417daac0ff6bbfc27f76
Note that both formats utilize the same unique identifier, indicating that this is the same meeting. But since the phone registered to Skype for Business cannot leverage the first URL then continues to see this invitation as a Skype meeting and then attempts to connect to the conference URI above. As far as the phone is concerned though it thinks it is talking to a Skype for Business MCU, but in reality it has been pointed to the gateway (focus:id:teams:2:0!19:) which then handles the rest of the connection to the actual Teams MCU and locates the correct meeting via the provided meeting ID (NQG2ODNz…).
Hybrid Mode
The mode is the only option which is supported by Microsoft for interoperability when the Trio is deployed as video-enabled when paired with a Poly Visual Plus (Visual+) or Visual Pro solution. This is because the Trio will leverage the supported Cloud Video Interop (CVI) approach by joining Microsoft Teams meetings using the Poly RealConnect Service.
The Hybrid name comes form the fact that the Trio can support multiple concurrent registrations to different SIP-based platforms and yet still join native Teams meetings with video and desktop sharing capabilities. One basic configuration option is to have a single line registered natively to Skype for Business to retain any existing functionality as well as utilize Enterprise Voice in Skype for PSTN connectivity, but then leverage a second (unregistered) line to join Teams meetings by placing standards-based SIP calls directly into the Azure-based interop service. Another common option comes into play when another common IP-PBX platform (e.g. Cisco or Avaya) is used in the environment and PSTN connectivity is not provided by Skype or Teams. This configuration is a true ‘hybrid registration’ option as the Trio will sustain multiple concurrent SIP registrations: one to the PBX platform for voice calling and a second to Skype for Business. The third line can be used for unregistered calls in to the CVI service or even be actively registered to any standards-based video proxy (e.g. Poly DMA/RPAD, Cisco VCS/VCS-E, etc.) for eventual routing into the video interop service (or alternatively the Poly Clariti-based configuration of RealConnect for Microsoft Teams interop.
In short, the Hybrid approach is the most flexible as it can be used to connect into any number of IP-based voice platforms and/or meeting solutions. It is not uncommon to see a Trio configured to support joining meetings scheduled on several different meeting services like Skype for Business, Microsoft Teams, Cisco WebEx, Zoom, etc. all in the same room.
Configuration
The example configuration in this article will address a single use-case, showing how register the Trio to Skype for Business and also configure it so that RealConnect will be used to join Teams meetings. This approach still retains existing Skype for Business functionality, only leveraging the interop service for joining Teams meetings
Before configuring the Trio itself a set of UCS parameters will need to be prepared to import into the phone. This is accomplished by creating a custom configuration text file and saving it with a .cfg file extension. There are several applicable parameters, most of which are required to successfully place calls into the RealConnect Service from the Trio. Only a few of the parameters need to be customized, while some of the parameters can be omitted depending on the desired capabilities.
At minimum the following parameters are required to allow the Trio to place a SIP call into RealConnect by using an additional, unregistered line. As mentioned above this specific example will configure the Trio to use Line 2 to place these calls, but for a Trio using a different configuration with potentially more than 2 registrations then simply alter the following example to use an available line number.
| Attribute | Value |
| call.autoOffHook.2.contact | 680450644@t.plcm.vc |
| call.autoOffHook.2.enabled | 1 |
| call.teluri.showPrompt | 0 |
| dialplan.2.applyToDirectoryDial | 1 |
| dialplan.2.digitmap | ^.+@t\.plcm\.vc$ |
| dialplan.2.digitmap.mode | regex |
| dialplan.2.digitmap.timeOut | 4 |
| dialplan.digitmap.lineSwitching.enable | 1 |
| exchange.meeting.realConnectProcessing.outboundRegistration | 2 |
| exchange.meeting.realConnectProcessing.skype.enabled | 0 |
| exchange.meeting.realConnectProcessing.teams.enabled | 1 |
| reg.2.address | trio |
| reg.2.keepalive.sessionTimers | 1 |
| reg.2.label | Teams Meeting |
| reg.2.server.1.address | t.plcm.vc |
| reg.2.server.1.register | 0 |
| reg.2.server.1.transport | TCPpreferred |
| reg.2.srtp.offer | 1 |
| reg.limit | 2 |
The three highlighted parameter values above must be customized as explained below.
- Most important is the specific Tenant Key (e.g 680450644) assigned to the Office 365 tenant where the RealConnect Service is used, as this controls which tenant entry queue is called when simply tapping the new line key which will appear on the phone.
- Also enter the preferred name used to identify the phone in SIP calls (e.g. trio); this name can be pretty much anything unique to the specific device except for the SIP URI of the account already registered to Skype for Business as that would cause a conflict.
- Finally select the desired label name which will appear under the new Line key button on the Trio’s home screen (e.g. Teams Meeting).
The following text can be copied into a new file and then saved as with a .cfg file extension for importing into the phone in a later step.
<?xml version=”1.0″ encoding=”utf-8″ standalone=”yes”?>
< !–Description: Template for configuring a Trio to connect and dial into Teams RealConnect via an unregistered Line 2. The Lobby will be autodialed when Line Key is selected.–>
< PHONE_CONFIG>
<ALL reg.limit=”2″ dialplan.digitmap.lineSwitching.enable=”1″ call.autoOffHook.2.contact=”680450644@t.plcm.vc” call.autoOffHook.2.enabled=”1″ dialplan.2.applyToDirectoryDial=”1″ dialplan.2.digitmap=”^.+@t\.plcm\.vc$” dialplan.2.digitmap.timeOut=”4″ dialplan.2.digitmap.mode=”regex” reg.2.address=”trio” reg.2.keepalive.sessionTimers=”1″ reg.2.label=”Teams Meeting” reg.2.server.1.address=”t.plcm.vc” reg.2.server.1.register=”0″ reg.2.server.1.transport=”TCPpreferred” reg.2.srtp.offer=”1″ exchange.meeting.realConnectProcessing.teams.enabled=”1″ exchange.meeting.realConnectProcessing.outboundRegistration=”2″ call.teluri.showPrompt=”0″ />
< /PHONE_CONFIG>
(Note that is configuration is identical to the “Trio-Teams-RealConnect-Line2-unregistered-Template” provided in the Polycom Device Management Service (PDMS).)
As mentioned above this specific example will configure the Trio to use Line 2 to call the RealConnect Service to join a Teams meeting. If it is preferred to move this functionality to a different line number for phones with more than a single registration then simply update each call.autoOffHook, dialplan, and reg parameter to change the .2. to the desired line number (e.g. 3). Also change the the exchange.meeting.realConnectProcessing.outboundRegistration parameter to match the same line number (e.g. 3) and finally set reg.limit parameter value from 2 to match the highest line number in the phone’s specific configuration.
On the Trio access the Settings menu and navigate to Advanced > Administration Settings > Network Configuration > Base Profile and then select the Skype for Business option. Tap the back arrow and then select Save Config which will immediately reboot the phone.
After the phone reboots tap the Sign In button and select the preferred option for registering to Skype for Business using the desired user account.
The next step is to apply the configuration file to the Trio which can be accomplished in one of several ways. If using a provisioning server solution with the Trio then that is the preferred approach, but for the purposes of this article the file will be manually imported into a single phone using the local web management administration interface. The web management interface is not available by default when the Trio is set to the Skype for Business profile, so it may need to manually be enabled. If it is already enabled on the Trio then skip this step.
On the Trio access the Settings menu and navigate to Advanced > Administration Settings > Web Server Configuration, enable Web Server, and then select the desired Web Config Mode (e.g. HTTP/HTTPS). Tap the back arrow and then select Save Config which will immediately reboot the phone.
After the phone has rebooted tap the hamburger menu in the top left corner and look for the device’s IP address as displayed in the menu (e.g. 192.168.1.167).
Open a web browser on a workstation and connect to the IP address using either HTTP or HTTPS, based on the previously-configured option(s) (e.g. https://192.168.1.167) and then sign in using the Admin account. (The default password is ‘456’.)
Go to the Utilities > Import & Export Configuration menu and then click Choose File under the Import Configuration section.
Select the previously created configuration file (e.g. Trio_RealConnect.cfg) and then click Import which should immediately trigger the Trio to reboot.
Behavior
After the phone reboots the additional line button (e.g. “Teams Meeting”) should appear on the home screen indicating that the new parameters were successfully imported. The new “Teams Meeting” line key can be used to simple call directly into the RealConnect Service’s entry queue which will prompt for the specific meeting’s video conferencing ID. The Meetings button on the home screen will provide aJoinbutton which can be used to connect directly into a scheduled Teams meeting.
USB Mode
This mode simply turns the Trio into a USB-only audio device for when it will be physically connected to any supported Microsoft system like the Microsoft Teams Room or a Surface Hub. The Trio no longer performs any registration and is turned into an accessory to perform as a microphone and speaker.
Configuration
On the Trio access the Settings menu and navigate to Advanced > Administration Settings > Network Configuration > Base Profile and then select the Microsoft USB Optimized option. Tap the back arrow and then select Save Config which will immediately reboot the phone.
Behavior
Once the phone reboots a very simple interface will appear. When the connected room system is not in an active call the display is relegated to only showing the Date and Time. When the connected room system is in a call then the Trio will display a call timer along with Mute and End Call buttons.
