Traffic prioritisation so voice and critical applications keep working when the link is saturated.
QoS matters at exactly one moment: when the link is full. Until then everything works and it looks unnecessary. The instant someone starts a large upload, voice quality collapses — and that's what QoS prevents.
The work is classification and policy. Voice and video get priority with guaranteed bandwidth and low latency; bulk transfers and backups are explicitly deprioritised so they use whatever is left instead of competing.
It has to be configured consistently end to end. QoS applied on your router but ignored across the transport network achieves nothing, which is why we prefer to control both.
Publishing exclusions is deliberate. Nobody in this market does it, and it's the fastest way to avoid a variation conversation later.
If yours isn't here, ask — we'd rather answer it before you buy than after.
Sometimes, and we'll tell you when that's the honest answer. But bandwidth doesn't fix prioritisation — a saturated 1 Gbps link degrades voice exactly like a saturated 10 Mbps one. If saturation is occasional, QoS is far cheaper than a permanent upgrade.
Only to the edge. Your markings aren't honoured beyond your provider, which is one of the real arguments for MPLS where performance is contractual.
Free site survey first. You keep the findings whether or not you buy.