DVMRP
RPM forwarding tree built on demand from a DVMRP group-independent routing table
Source-based trees, data-driven (broadcast-and-prune), implicit join, dense mode
TTL and admin scoping available; physical or tunnel interfaces possible
Limitations:
- distance-vector => slow to adapt to topology changes;
- Must store source-specific sate even when not on tree => more scaling problems
- No hierarchy (flat routing domain)