Direct Routing

Microsoft announced some Office 365 certificate changes last year: https://learn.microsoft.com/en-us/microsoft-365/compliance/encryption-office-365-tls-certificates-changes?view=o365-worldwide If you’re using Microsoft Teams Direct Routing you need to apply a new root certificate to your SBCs. More specifically if your SBC has “TLS Mutual Authentication” enabled on the Teams SIP interface then you MUST make this change. I would recommend making this change anyway and ASAP! How to check if TLS Mutual Authentication is enabled? Log into your AudioCodes SBC, navigate to Setup > Signalling and Media > Core Entities > SIP Interfaces. ...

History Unlike Lync & Skype for Business, Teams doesn’t have a method to handle unassigned numbers (yet). There is a UserVoice post here requesting the feature: https://microsoftteams.uservoice.com/forums/555103-public/suggestions/38673550-unassigned-number-range Typically the unassigned numbers feature was used to program ALL available number ranges in the system. A number was deemed “unassigned” if it was not populated as a LineURI against an SfB Object (i.e. User, Response Group, Application Endpoint etc). If an unassigned number received a call you had two options: ...

Enable-TeamsDRUsers GUI At the time of writing it’s not possible to enable Teams Direct Routing users via Teams Admin Center, only via PowerShell commands. This PowerShell script launches a WinForms GUI that can be used by anyone. This is useful for enabling or making changes to a couple of Teams DR users. Requirements - Microsoft Teams PowerShell module 2.0 or above - Teams Administrative Rights (Teams Service/Communications Administrator + Skype for Business Administrator) - Users must have a Phone System license ...

A very popular Topology for Direct Routing is to deploy a certified Session Border Controller into Microsoft Azure with SIP Trunks to Teams Phone System and SIP Trunks to a PSTN provider. There are Azure Datacentres all over the world, SBCs are rapid to deploy from Marketplace templates and SBC>Teams traffic effectively stays on the Microsoft CDN. Big carriers may have direct peering with Microsofts network, others will meet the Microsoft Network at Internet Exchanges (i.e. LINX in London). There’s no need to buy expensive WAN circuits and Compute costs for the SBCs are minimal, especially if on 3 year pricing. It’s just an awesome solution! ...

This post explains an easy way to block nuisance callers using an AudioCodes SBC. Whilst it’s possible to use New-CsInboundBlockedNumberPattern with Microsoft Teams, what if another type of PBX or Contact Centre hooked up to your SBC? These calls would bypass the Teams rule. Maybe you just want to do your blocking closer to the SIP carrier which is completely acceptable. I’m achieving this by using AudioCodes Dial Plans which are a super efficient way of routing calls rather than having lots of IP-to-IP rules or Number Manipulations. ...

Microsoft Teams with Calls Icon When enabling users for Microsoft Teams Direct Routing, I have noticed when configuring a user for Enterprise Voice, that it can take up to a day for the “Calls” icon to appear so users can make outbound calls using the Dial Pad. Users can successfully receive Inbound calls over DR immediately. You verify that your user is correctly configured for Teams DR: ...