04 · Network and QoS
This table is the QoS interview. It is also the ACL.
The QoS article’s initial ranges are audio UDP or TCP 50000–50019 at DSCP 46 EF, video 50020–50039 at 34 AF41, sharing 50040–50059 at 18 AF21, and calling and meeting signaling 50070–50089 at 40 CS5. Signaling ports are not configurable.
Browser joins do not use those fixed ranges. Mac and mobile hard-code audio as EF. Windows can follow policy, and the client process to match is ms-teams.exe, not the previous client’s name.
Audio DSCP 46, video 34, sharing 18, signaling 40. Browser joins do not use the fixed client ports.
Audio is 46 on ports 50000 to 50019. I can place the other three without a card.
If it fails: An ACL matches the old client or the wrong port range, so marks never land.
A colleague reports: Every remote user shows high RTT and the office does not. Where do you start?
Every remote user shows high RTT and the office does not. Test a call on the VPN and off it before you blame the carrier. Source: https://learn.microsoft.com/en-us/microsoftteams/qos-in-teams accessed 2026-10-14.
Which description of ExpressRoute is optional is accurate?
Teams does not require ExpressRoute. Local internet egress is the usual design. If you do use ExpressRoute, follow the current network article rather than assuming media is happier there. A contract for ExpressRoute is not a QoS design. Source: https://learn.microsoft.com/en-us/microsoftteams/prepare-network accessed 2026-10-14.
A colleague reports: Media was forced onto a long private path and RTT jumped. Where do you start?
Media was forced onto a long private path and RTT jumped. Decide the path, then mark DSCP on the path you actually use. Source: https://learn.microsoft.com/en-us/microsoftteams/prepare-network accessed 2026-10-14.
Around the call: compliance recording, workforce management, emergency location, analytics, CRM screen pop, and an agent with a human escape. Each one has its own failure.
An ACL matches the old client or the wrong port range, so marks never land.
Cisco CUBE is one of the SBC families named in this lab’s certification lesson. A certified release can be the Direct Routing SBC between Unified CM and Teams.
The tenant still needs a verified domain on the SBC FQDN, and the user still needs Teams Phone. The studio translator does not open a live AXL session. Confirm the current certified release before you build.
Teams Phone and Webex Calling are separate clouds. This lab does not describe a feature that registers a Webex Calling user into a Teams tenant.
A number move is usually a carrier port, a certified SBC, or a meetings interop product. Confirm before relying.
Unified CCE stays the ACD until you migrate it. Microsoft’s contact-center articles name Connect, Extend, and Unify. They do not name a UCCE connector in the notes this lab cites.
Voice into Teams is still Direct Routing or Operator Connect. The routing script stays on the contact-center product you bought. Confirm the vendor’s current model. Source: https://learn.microsoft.com/en-us/microsoftteams/teams-contact-center.
Copilot Studio, Azure Communication Services, and Graph are later tracks in this lab. Treat any uncited limit as confirm before relying.
Opened 2026-10. A row marked confirm did not open. Wikipedia is background. The Teams blog row is the community index.
