Teams: Direct Routing Review
Review
As we all know, the Direct Routing is well entering into a week of Public Preview mode.
As observed so far:
- The "Silk Codec" originally developed by Skype has become first priority Codec for PSTN Gateway(s) created in the Microsoft Office365 Tenant.
- Though MediaBypass is disabled by default but when the call is established, the on-premise SBC, in my case, Sonus 1K, is showing "Connected with Media Bypass" as shown. Please kindly highlight if it's not what you saw in your SBC gateway.
- One of the compelling capabilities in Direct Routing is that setting up High Availability (HA) for on-premise SBC Gateways (PSTN Gateways) is a matter of running a few commands (will write up a more elaborated guide) in the Office365 Tenant through SFB Online PowerShell.
- And there is a mechanism/parameter to disable a particular SBC Voice Gateway(s) when it is needed a "downtime" for firmware upgrade, servicing or even to bring it down on-demand basis due to a fault by setting "Enabled" to "False" as shown in the Get-CsOnlinePSTNGateway output.
- A user homed in SFB Online MUST use the Teams client to make a successful incoming and outgoing call through SBC Voice Gateway (PSTN Gateway) configured/integrated with Direct Routing. In my SFB-Hybrid environment, for a testing purpose, I used an SFB Online homed user logged into SFB client and made a call, it was NOT using the SBC Voice Gateway (PSTN Gateway) I configured/integrated with the Direct Routing but instead it went to the On-Premise Hybrid Frontend server which in turn routed the call to respective SBC Voice Gateway.
- Most importantly, and equally interesting is how do we go about migration from current SFB Online users to Microsoft Teams? I'll cover more about it in my next write-up.
https://gallery.technet.microsoft.com/site/view/file/200478/1/1.png
Enhancements needed for Direct Routing
Built-in Monitoring
One fundamental and critical enhancement Direct Routing needs is to have a "monitoring feature" - as basic as an admin/support team getting an email alert when a paired SBC (PSNT Gateway) is down by monitoring, for example, port 5061 - this should be a built-in fundamental component of DR - helping customers achieve more and complementing what DR already has.
Office365 Backend Logging
Also, Direct Routing should have a "logging feature" for troubleshooting calls routing related issue in the Office365 Tenant backend, for example; I have a Microsoft Calling Plan in US HQ configured with a dozen of Direct Routing PSTN Gateways in 5 different regions -- we need to have a visibility on whether customer SBC (PSTN Gateway) are getting signalling from Direct Routing SIP Proxy, whether Teams calls are routed successfully from Direct Routing Media Processor to PSTN Gateway on-premise -- currently Direct Routing doesn't have these logging features yet. I believe, Microsoft will gradually turn these feature on in the newly launched Microsoft Teams Admin Portal in the future?
It would be better if Teams client has comprehensive client-side logging features like what SFB client does (Lync-UccApi-x.UccApilog), having that will not only help reduce support calls to Microsoft as well as troubleshoot end-users' issues more effectively. And Yes, logs should be able to open and view using the Snooper or Teams Snooper?
By the way, we can retrieve Microsoft Teams' log files as mentioned here. /en-us/microsoftteams/log-files . However, they are not as friendly and instructive as of SFB client log file.
Call forwarding is working fine.
CodecPriority can be changed for PSTN Gateway configured with Direct Routing.
DR currently doesn't support
As of now, Call transfer feature is not available yet in Direct Routing?, once I clicked "Transfer or Consult then transfer" the call was immediately put on hold? Anyone could verify on that?
Peeking inside Microsoft Direct Routing.
sip-all.pstnhub.microsoft.com is load-balanced by Akamai CDN as shown in the DNS lookup leveraging on its global network coverage to better serve customers.
sip-all.pstnhub.microsoft.com. IN A ; ANSWER sip-all.pstnhub.microsoft.com. 3593 IN CNAME sip-all.pstnhub.akadns.net. sip-all.pstnhub.akadns.net. 29 IN A 52.114.132.46 sip-all.pstnhub.akadns.net. ``29 IN A 52.114.14.70 sip-all.pstnhub.akadns.net. ``29 IN A 52.114.7.24 sip-all.pstnhub.akadns.net. ``29 IN A 52.114.148.0 sip-all.pstnhub.akadns.net. ``29 IN A 52.114.75.24 sip-all.pstnhub.akadns.net. ``29 IN A 52.114.76.76 ``
Backend SIP Proxy servers are running on TCP port 8000 as shown in the SIP session message.
Current Direct Routing SIP server version (world-wide) is "v.2018.5.23.1" as shown -- a hint to see amelioration, improvement, betterment in the future version.
As seen in the SIP session message, Teams Client's most preferred Audio Code is 104 = Silk Wideband Codec, immediately followed by 117=G.722
https://i1.gallery.technet.s-msft.com/direct-routing-fro-review-1-a3f492e8/image/file/200498/1/4-call-transfer%20-%20copy.png Setting up High Availablity for PSTN Gateway in Direct Routing.
1.
**Step-1 - Create two PSTN gateways.** New-CsOnlinePSTNGateway -Fqdn sbc1.thetnaing.com -SipSignallingPort 5061 -ForwardCallHistory $true -Enabled $true New-CsOnlinePSTNGateway -Fqdn sbc2.thetnaing.com -SipSignallingPort 5061 -ForwardCallHistory $true -Enabled $true
Step-2 - Create 1 more more Routes associating with 1 or more PSTN Gateways (creating HA) New-CsOnlineVoiceRoute -Identity "Singapore Local" -NumberPattern "^\65\d{8}$" -OnlinePstnGatewayList sbc1.thetnaing.com,sbc2.thetnaing.com -Priority 1 -OnlinePstnUsages "Singapore" New-CsOnlineVoiceRoute -Identity "All calls" -NumberPattern "." -OnlinePstnGatewayList sbc1.thetnaing.com,sbc2.thetnaing.com -Priority 1 -OnlinePstnUsages "Singapore"
Step-3 - Create Voice Routing Policy New-CsOnlineVoiceRoutingPolicy "SingaporeVRP" -OnlinePstnUsages "Singapore".
Step-4 - Grant Voice Routing Policy to a user(s) Grant-CsOnlineVoiceRoutingPolicy -Identity "thet@thetnaing.com" -PolicyName "Singapore"
Above steps are also mentioned in the slide number 29-to-32 in the attached PPTx deck.
https://i1.gallery.technet.s-msft.com/direct-routing-fro-review-1-a3f492e8/image/file/200544/1/1.png
