Does QoS on letter Q share fate with other letters?

The control plane is shared. Data-plane queues for QoS stay isolated, so incident q-01 cannot drain neighbor letters.

Where is QoS measured first?

From Santiago (SCL) toward Bogotá. A global average is not an SLO for letter Q.

How fast is rollback for q-03?

The runbook is a command plus a named owner. There is no wait for a weekly change freeze.

Is transit the default path?

No. Peering in Miami is default; transit to São Paulo is overflow and is billed that way.

QoS queues that protect control traffic first

When a link saturates, BGP, DNS and health probes must still pass. XServ marks that traffic before bulk transfers.

QoS: Why it matters on this continent

Design for QoS on letter Q starts in São Paulo (GRU). Runbook q-01 keeps a single owner, a written rollback, and a traffic split that can be reversed without a global freeze. Neighbors in Santiago only take overflow after the local pool fails a health window.

QoS: How XServ runs it day to day

Probes for QoS (q-02) leave Santiago every 15s toward Bogotá. XServ pages the named owner if loss or RTT crosses the letter budget. A probe never shares a queue with bulk transfers, so a saturated WAN does not hide a dead PoP.

QoS: What operators should measure

Policy for QoS is versioned as q-03. Operators measure error rate, p95 from Bogotá, and time-to-rollback — not a worldwide average. Changes land in Bogotá first, then Miami, with a hold if either region regresses.

QoS: Failure modes we actually see

Capacity notes for q-04 assume rainy-season power in Miami and festival peaks toward São Paulo. The failure we actually see is a single uplink, not a cartoon partition of the whole continent. Spare ports and a second provider sit on the same runbook.

QoS: How this letter ties to the rest

Handoff from letter Q QoS into the rest of the platform uses the same request IDs as the gateway. Runbook q-05 names who accepts the ticket after São Paulo pages out. Santiago does not silently inherit the incident.

QoS: A note on cost and transit

Rollback for q-06 is a documented command, not a hope. Transit is billed as backup while QoS prefers peering in Santiago. If cost spikes, the runbook cuts overflow to Bogotá before touching customer prefixes.

QoS design Q-01

QoS probe Q-02

QoS policy Q-03

QoS capacity Q-04

QoS handoff Q-05

QoS rollback Q-06

QoS peering Q-07

Peering for QoS (q-07) prefers the IX fabric that already carries last-mile ISPs in Bogotá. Session counts and prefix limits are on the same page as the Miami backup path.

QoS cache Q-08

Cache rules for QoS on q-08 keep language-correct objects near Miami. São Paulo is a sibling cache, not an origin. TTLs are short enough that a bad asset does not live through a weekend.

QoS headers Q-09

Headers for q-09 carry the letter, the region (GRU) and a request id. QoS debugging in São Paulo should not require a packet capture in Santiago first.

QoS timeouts Q-10

Timeouts on q-10 are tighter than the WAN RTT to Bogotá. QoS in Santiago fails fast and retries once; a third try needs a human because it is no longer a blip.

QoS regions Q-11

Region names on q-11 match DNS and tickets: Bogotá / BOG, with Miami as the documented pair. QoS dashboards never say “LATAM” as if it were one RTT.

QoS docs Q-12

Public docs for letter Q stay aligned with identifier xserv-q-pack. Page q-12 is the QoS slice operators search before the homepage. Edits in Miami show up in São Paulo on the next publish.