Which multicast address does EIGRP use to send hello and updates packets?

EIGRP uses the multicast address 224.0.0.10 for sending hello packets, updates, and other EIGRP messages. This address is reserved specifically for EIGRP and ensures that EIGRP messages are received by all EIGRP-speaking routers on the broadcast domain without disturbing other protocols. By contrast, 224.0.0.5 and 224.0.0.6 are used by OSPF (all OSPF routers and designated routers respectively), while 224.0.0.9 is used by RIPv2. Using protocol-specific multicast addresses improves efficiency by allowing devices to filter unwanted traffic at the hardware layer.