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Interviews, incidents, and design drills
Cited answers in the lesson body, one-variable incidents, and interconnect checklists.
7 rooms42 quiz items
Rooms
- Signaling drill with the cited answer
Each signaling answer is written here, with the RFC, before the quiz asks it.
- Media drill with the cited answer
488, 422, telephone-event, RTP, and the SRTP keying choice, each answered in the prose.
- SBC drill with the cited answer
B2BUA, where PSTN SIP lands, the trusted list, and Teams TLS, answered in the body.
- Symptom, ladder, one packet, one variable
The sequence is symptom, ladder, one packet, change one variable. The log in this lesson is synthetic.
- An interconnect checklist, not a config dump
Record TLS, codecs including telephone-event, E.164, trusted addresses, OPTIONS, and the SRTP keying choice.
- CUCM, a certified SBC, and Teams Direct Routing
CUBE or another certified SBC can sit between CUCM and Teams. No architecture SKU is invented here.
- When the RFC number moves
SDP, ICE, STUN, and TURN moved. The RFC Editor banner beats a blog, and an uncited successor stays an open question.
Ecosystem
SIP does not replace workforce management, quality monitoring, CRM, emergency policy, or a messaging registry. It is the session seam those systems hang from. Compliance notes on this page are educational and are not legal advice.
Sources and go deeper
- RFC 3261 §8 — last checked 2026-10
- RFC 3261 §12 — last checked 2026-10
- RFC 3261 §17 — last checked 2026-10
- RFC 3261 — last checked 2026-10
- RFC 3261 §13 — last checked 2026-10
- RFC 6026 — last checked 2026-10
- RFC 3261 §21 — last checked 2026-10