Capture at the network egress, not only on the PC.You want the DSCP value on the wire after the VPN, the switch, and the router.Port mirroring is the usual way.
If audio ports 50000–50019 leave the building marked 0, the client policy missed or a device rewrote the mark.Fix that before you argue about codecs.
Prove QoS at the network egress.A mark that dies on the VPN is not a design.
A site map for Proving the mark survived. LBR is toll-bypass control, not emergency location by itself.Sequence. Counts in this drawing are teaching order, not customers.
Add an 18-byte Ethernet header to the G.711 20 ms packet and the figure is 87.2 kbit/s per direction. WAN sizing that stops at layer 3 is already short on a LAN you police. Source: https://learn.microsoft.com/en-us/microsoftteams/qos-in-teams accessed 2026-10-14.
A colleague reports: The policer drops the header you forgot. Where do you start?
The policer drops the header you forgot. Use 87.2 kbit/s when the policer sees Ethernet. Source: https://learn.microsoft.com/en-us/microsoftteams/qos-in-teams accessed 2026-10-14.
Which description of Comfort noise and SID is accurate?
Silence suppression changes the average bitrate. Do not size a link only from a G.711 average that assumed comfort noise you did not enable. The peak is still the number that fills the queue. Source: https://learn.microsoft.com/en-us/microsoftteams/qos-in-teams accessed 2026-10-14.
Shortest media path Microsoft’s network guidance prefers a short path to the Microsoft network, without a proxy in the media path. Config: Egress Teams media locally. Do not hairpin a branch through a distant data center unless you mean to. Fault: One city’s CQD is poor and the firewall team finds a proxy.
VPN and real-time media Microsoft recommends that you avoid sending real-time Teams media through a VPN. QoS on the VPN does not fix the extra delay. Config: Test a call on the VPN and off it before you blame the carrier. Fault: Every remote user shows high RTT and the office does not.
ExpressRoute is optional 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. Config: Decide the path, then mark DSCP on the path you actually use. Fault: Media was forced onto a long private path and RTT jumped.
QoS markers enabled The Teams admin center setting that allows clients to insert DSCP. Without it, a correct ACL still sees unmarked client traffic from managed endpoints that honor the policy. Config: Turn the insert-markers setting on, then verify at the WAN edge. Fault: The network is marked and the clients were never told to mark.
Sister technologies
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.
Config and troubleshooting
The laptop looks correct and the WAN sees best effort.
Cross-platform bridges
CUCM
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.
Webex
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.
UCCE
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.
Quality of service — Wikipedia — last checked 2026-10. Wikipedia fallback for background. Confirm the vendor page before you change a tenant
Microsoft Teams blog index — Community — last checked 2026-10. Community index for the Microsoft Teams blog. This is the index, not a claim that a post discusses this room
