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Navigating Microsoft Teams Direct Routing


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Direct Routing for Microsoft Teams provides those implementing Teams Phone System with the flexibility to use their own session border controllers (SBCs) and SIP trunking services to connect Teams to the PSTN. Compared with Microsoft’s own Calling Plan PSTN connectivity service, Nemertes finds five adoption drivers for Direct Routing:
  1. Faster migration to Teams – Direct Routing allows companies to maintain control over their phone numbers, reducing the complexity of migrating to Teams by eliminating the need to port phone numbers to Microsoft.
  2. Lowers costs – Companies adopting Teams on average spend about $7.91 per month/per phone line for PSTN connectivity (not including staffing and management costs), compared to $12 for Microsoft’s domestic-only Calling Plan or $24 per-month for international plans. Direct Routing enables organizations to implement or preserve existing least-cost-routing of calls, especially for international locations, and to take advantage of new billing models such as fractional per-minute pricing.
  3. Increases flexibility – Maintaining one’s own SBCs and SIP trunking services provides the opportunity to avoid being locked into Microsoft, and to easily support other communications platforms, such as on-premises or cloud contact center.
  4. Supports global calling needs – Such as local phone number presence in regions not supported by Microsoft Calling Plan
  5. Minimizes disruptions – Allows for the continued support of on-premises PBXs during the transition and avoids having to wait until current SIP/PSTN contacts expire before making the transition to Teams
Given these advantages of Direct Routing, it’s no wonder that 89% of Nemertes research participants adopting Microsoft Teams Phone System are doing so via Direct Routing.
Successfully implementing Direct Routing requires a multi-step approach, with the transition to Teams often serving as an inflection point to consider new SBC and SIP trunking options. Key tasks include:
  1. Assessing current SBCs to determine if they are certified for use with Teams or evaluating the potential benefits of shifting SBCs from appliances to virtual software, or SBC-as-a-Service bundled as a cloud service with a SIP-trunking offering
  2. Evaluating existing SIP trunking services to compare the cost to alternatives
  3. Determining the ability of SIP trunking services to support automated provisioning as well as additional advanced features including SMS and APIs to enable integration of calling into other business applications
  4. Evaluating performance management and analytics capabilities to ensure high-quality Teams calling experiences
  5. Considering the ability of SBC and SIP trunking providers to support enhanced E911 capabilities including support for Microsoft dynamic emergency calling, as well as security desk notification and granular location transmission as required by Kari’s Law and RAY BAUM’S Act
Additional considerations in selecting a SIP trunking provider to support Direct Routing include network connectivity options, geographic reach, reliability, and whether a provider has directly peered with other top-level PSTN network service providers.
Compared to Microsoft Phone System Calling Plan, Direct Routing coupled with bring-your-own SBC and SIP trunking may offer significant benefits in terms of costs, flexibility, and ease of migration. Those adopting Teams Phone System should carefully evaluate Direct Routing, as well as providers offering SBC and SIP trunking services.