Abbreviated as DUAL, the diffusing update algorithm
is a routing protocol used by
EIGRP to calculate
and create routing tables to determine whether a path is looped or loop-free. It
also allows a router running EIGRP to find alternate paths without waiting on
updates from other routers. The diffusing update
algorithm (DUAL) was developed at SRI International
by Dr. J.J. Garcia-Luna-Aceves.
Enhanced Interior Gateway Routing Protocol (EIGRP) EIGRP contains several important protocols that greatly increase its operational efficiency relative to other routing protocols. One of these protocols is the Diffusing update algorithm (DUAL) developed at SRI International by Dr. J.J. Garcia-Luna-Aceves. DUAL enables EIGRP routers to determine whether a path advertised by a neighbor is looped or loop-free, and allows a router running EIGRP to find alternate paths without waiting on updates from other routers.