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Evaluating Direct Routing for Microsoft Teams telephony

Direct Routing for Microsoft Teams may be the best path to the PSTN for most companies. But organizations should weigh their specific needs when choosing a Direct Routing partner.

Microsoft Teams has come a long way since it was first introduced as the successor to Skype for Business. The pandemic only accelerated the adoption of Teams, as many organizations relied on cloud-based collaboration software to maintain workflows and business continuity as employees worked from home.

Organizations that have successfully used Microsoft Teams over the last year for collaboration should consider using Teams as their phone system, said Kevin Kieller, co-founder of Microsoft consulting firm EnableUC. While Teams users can make peer-to-peer calls within the platform over the internet, Teams is also capable of being an enterprise PBX for many organizations, he said.

Voice is often the first communication channel used when someone needs to get in touch with a company or solve a problem, said Alex Gruber, vice president of product management at Vonage.

"Getting voice embedded into Teams is really bringing the outside world to the inside world," he said.

Kieller, Gruber and other industry insiders spoke at an Enterprise Connect virtual summit on Direct Routing for Microsoft Teams and why Teams customers should consider using the platform as a phone system.

Connecting Teams to the public switched telephone network (PSTN) offers organizations a few benefits, Kieller said, including the following:

  • Consolidation and simplification. Organizations can consolidate their phone system to a single platform to make both PSTN and internet-based calls and transition off a legacy PBX.
  • Resiliency. With many employees still working from home, PSTN connectivity through Teams can address poor internet connections by enabling users to make and receive Teams calls on their mobile device.
  • Direct inward dialing (DID). With the mobile app, employees can make calls and have their corporate DID number display on caller ID rather than their personal mobile number.

Organizations with on-premises systems are accustomed to having enterprise-grade functionality, which is not always available with cloud-based telephony, said Shawn Cooke, senior product specialist at Masergy Communications.

Getting voice embedded into Teams is really bringing the outside world to the inside world.
Alex GruberVice president of product management, Vonage

"Moving to the cloud, there ought to be some comparable exchange, not just the promise of cloud telephony," he said.

Teams has lagged in offering feature parity to on-premises Skype for Business. But, now that Teams offers PSTN connectivity, it can fill some of the gaps between cloud-based and on-premises telephony. Microsoft offers two paths to PSTN connectivity, and the question for organizations is which path is the best fit for their business. For many, the answer will be Direct Routing, Kieller said.

Direct Routing vs. Calling Plans

Microsoft offers Calling Plans and Direct Routing to connect to the PSTN. With Calling Plans, Microsoft is the sole carrier for the Teams phone system. Calling Plans are easy to deploy and a nice way to pilot Teams voice, but they do have limitations, Kieller said.

While an international plan is available, it is not available in all countries. This presents a challenge for global and multi-tenant organizations. Calling Plans also don't support integrations with existing equipment and use a pay-per-user price model, which can be costly for larger organizations, he said.

The second approach to a Microsoft Teams phone system is Direct Routing. Approximately 80% of medium and large organizations use this approach, Kieller said. Direct Routing is available worldwide and enables organizations to integrate Teams with their existing PBXs and analog devices, as well as continue existing carrier contracts.

However, configuring Direct Routing for Microsoft Teams is more complex compared with Calling Plans and may require some Capex spending for equipment. Direct Routing also requires additional management of existing on-premises hardware, he said.

Direct Routing requirements and considerations

Direct Routing has some requirements that organizations must meet, Kieller said. First, organizations must have the appropriate licensing to enable the phone system. Organizations also need a physical or virtual session border controller (SBC) that connects through a Session Initiation Protocol (SIP) trunk to the PSTN.

Organizations also need to consider their own requirements for using Teams as a phone system, including reporting, monitoring and management. For example, organizations should determine the level of monitoring and reporting they require from a Direct Routing partner. Some providers may only monitor the quality of PSTN calls, while others may also include peer-to-peer calls placed over the internet, Kieller said.

Organizations must also decide how much phone system management they want to dedicate in-house or offload to their provider.

"A number of partners can help you manage Teams voice on an ongoing basis should you decide that's not a focus for your IT resources," he said.

This will also help organizations decide which type of provider to use, as some providers will only manage and monitor basic SIP connectivity, while others will take on more responsibilities, like moves, adds and changes.

Choosing a Direct Routing partner

While Microsoft has improved the Teams phone system, some organizations may find feature gaps for their particular voice needs, such as attendant consoles and contact center functionality. Here is where organizations can find value in working with a third-party provider.

"Partners can both help you set up Teams voice and help you fill any gaps in functionality for your organization that you've identified," Kieller said.

Direct Routing partners come in three different flavors, said David Lee, vice president of platform products at RingCentral.

First are basic access providers, which typically provide only SIP connectivity between Teams and the PSTN. The organization is responsible for managing an SBC. These types of providers don't offer PBX capabilities, he said.

Second are Direct Routing-as-a-service providers, which manage SBC and SIP connectivity. They also offer basic PBX capabilities, such as call minutes and phone numbers, Lee said.

Third are enhanced Microsoft Teams telephony services in which the third-party provider includes SBC and SIP connectivity, advanced support and advanced PBX capabilities, such as toll-free dialing, extension setup and voicemail greetings, he said.

Organizations evaluating Direct Routing partners need to determine the level of support and functionality they require to choose the right provider for their telephony needs.

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