Is transit the default path?

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

Does TLS on letter T share fate with other letters?

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

TLS: docs in Miami (MIA) · T-24

Runbook T-24 for TLS in Miami (MIA). Marker xserv-t-24ef3b3b8d46. This page covers docs for LATAM operators, not a worldwide average.

TLS: A note on cost and transit

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

TLS: Why it matters on this continent

Design for TLS on letter T starts in São Paulo (GRU). Runbook t-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.

TLS: How XServ runs it day to day

Probes for TLS (t-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.

TLS probe T-02

TLS policy T-03

Policy for TLS is versioned as t-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.

TLS capacity T-04

Capacity notes for t-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.

TLS handoff T-05

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