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I recently started looking at implementing Direct Routing in my organisation so I have been doing a fair bit of reading about it. Media bypass, on the face of it, seems like an absolute “must have” when it comes to Direct Routing. However, nothing is ever simple and due to the nature of Microsoft Teams being a cloud-based service as well as being relatively young, media bypass isn’t quite as simple as it could be. In it’s current guise Media Bypass has the following limitations: Media bypass is currently only supported with ICE Lite on the SBC side. This means that clients currently have to connect to the SBC on it’s public interface. This might be difficult for some enterprises to configure which might lead to firewall hair-pinning and actually diminish the advantages of media bypass anyway. Media bypass is not supported by the Teams web/browser clients. They recommend not enabling media bypass if the browser clients are going to be used. Media bypass is not supported for 3PIP devices...

  If you are playing around with location based routing or local media optimization in Microsoft Teams Direct Routing, you will have no doubt had to configure Trusted IPs and network sites in Microsoft Teams. In order for LBR or LMO to work correctly, a client needs to be determined to be “internal”. This is done using Trusted IPs and network subnets in the Network Topology section of the Teams Admin Center. It is often wise to check if what you have configured is correct. I’ve also found that trusted IPs can take a while to filter through the Teams service, so instead of waiting for stuff to miraculously work you can use the process below to check what your client thinks is going on. Alternatively, maybe the networking team has snuck in a new subnet without telling you, or the security team have changed the firewall IP and the clients no longer think they’re internal? I have also found that the  MediaLine_Description_ReflexiveLocalIPAddress_IPAddr  or  Connectivity_...