Gap audit
From fundamentals to the job
Every block below is a page in this lab. The deep campus still holds the long library.
Architecture
Identity, signaling, media, policy, observe.
Deployment
Publisher, time, DNS, certificates, backups.
Configuration
Lab-safe walkthroughs. Not a change window.
Migration
Checklist and a cutover you can roll back.
Playbooks
One hypothesis, one change, one capture.
Firewall matrix
Who talks to whom, from the CUCM 15 port chapter.
PSTN choices
Trunk, Calling Plan, local gateway, Operator Connect, Direct Routing.
Security
Toll fraud, TLS, SRTP, and what this lab will not decide.
Licensing
Smart Licensing, Webex subscriptions, Teams Phone.
Certifications
The February 2026 Cisco exam names.
Interview
Questions from the bank, and a career path with no invented salaries.
What's new
2026 items that are cited, and rows marked unverified.