Here is a list of the most important EIGRP features:
- advanced distance vector routing protocol
- classless routing protocol
- supports VLSM (Variable Length Subnet Mask)
- converges fast
- supports multiple Network layer protocols (IPv4, IPv6, IPX, AppleTalk…)
- uses multicast address of 224.0.0.10 for routing updates
- sends partial routing updates
- supports equal and unequal-cost load balancing
- supports manual summarization on any router within a network
- by default, uses bandwidth and delay to calculate its metric
- Cisco proprietary
- supports MD5 authentication