EIGRP (Enhanced Interior Gateway Routing Protocol) uses the Diffusing Update Algorithm (DUAL) to calculate the shortest path to each network and allows for unequal cost load balancing with the variance command. OSPF (Open Shortest Path First), on the other hand, uses the Dijkstra algorithm to build a shortest-path tree for each route and does not support unequal cost load balancing by default. References: The Implementing and Operating Cisco Service Provider Network Core Technologies (SPCOR) source book would contain more information on the differences between EIGRP and OSPF, including their algorithms and load balancing capabilities.