LISP: who you are and where you are, kept apart
Every mechanism has a step-by-step animation, the configuration explained line by line and the exam notes. Where a parameter changes the outcome, you get a simulator in which you change it yourself.
TL;DR
LISP separates identity from location: hosts have EIDs (stable addresses, not routed in the core), edge routers have RLOCs (addresses routed normally), and a mapping system — Map-Server and Map-Resolver — keeps the correspondence between them. The ETR registers its prefixes at the MS with an authenticated Map-Register; the ITR, at the first packet toward an unknown EID, sends a Map-Request and puts the Map-Reply in its map-cache for 24 hours; from then on it encapsulates directly in UDP 4341, with 36 bytes of overhead. Priority and weight give multihoming controlled by the destination, the Instance ID separates VRFs, SMR corrects the caches when a host moves, and PITR / PETR connect to the world that doesn't speak LISP. In SD-Access, LISP remains only the control plane, and the data travels in VXLAN-GPO.
How to read the notes: red = critical for the exam, green = theory, blue = numbers, yellow = pitfalls, cyan = differences RFC ↔ Cisco, classic LISP ↔ SD-Access, and between platforms. In the animations, the configuration lines used in the current step are highlighted automatically; the ← → arrows change the step when the animation is selected.
The analogy, in short
Think of a city where people have stable names, buildings have postal addresses, and at the city hall a civil registry office knows who lives where. Letters aren't sent to the person's name but to the building's address, in an outer envelope that the doorman there opens; if the person moves, only the line in the registry changes, not their name.
The model holds up to §9. From §10 on (address families, SD-Access, LISP-SEC), it breaks; see the full analogy and its limits in §15.