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An interconnect checklist, not a config dump
Record TLS, codecs including telephone-event, E.164, trusted addresses, OPTIONS, and the SRTP keying choice.
Learn in 5 minutes
- Fill the six checklist rows
- Keep E.164 with the tel URI RFC
- Stop before a full configuration dump
Visual
Each row is a decision. None of them is a full IOS build.
Worked example
Find two rows on the INVITE The INVITE hop carries a number and an offer. Which checklist rows are those?
- Press Play.
- Step until the hop named in the question.
- Inspect that message and answer the check.
Fault
The design ticket pastes a full dial-peer list, a private key, and a queue map, and it never records whether keying is SDES or DTLS-SRTP.
The deliverable is the checklist. Keying is RFC 4568 or RFC 5764.
Quiz
Ecosystem
Glossary, sister systems, and the integration seam for this room.
CRM Screen pop uses data the contact center already has: ANI, DNIS, case id. Those values may arrive in SIP headers or in a CTI event after the call is up. The CRM is not a SIP element.
Sources and go deeper
- Direct Routing OPTIONS and TLS — last checked 2026-10
- RFC 4733 — last checked 2026-10
- RFC 3264 — last checked 2026-10
- RFC 3966 — last checked 2026-10
- Cisco CME toll-fraud prevention — last checked 2026-10
- Cisco SRST trusted IP authentication — last checked 2026-10
- RFC 3261 §11 — last checked 2026-10
- RFC 3711 — last checked 2026-10
- RFC 4568 — last checked 2026-10
- RFC 5764 — last checked 2026-10
- RFC 3246 — last checked 2026-10
- RFC 4594 — last checked 2026-10
- Cisco CUBE basic SIP configuration — last checked 2026-10