© 2007 Cisco Systems, Inc. All rights reserved. ICND2 v1.0—5-1 Module Summary  EIGRP is a classless routing protocol that supports VLSM.  Path selection is based upon several factors.  EIGRP keeps a next-best alternative path, called a feasible successor, for fast convergence.  EIGRP supports unequal-cost load balancing.  EIGRP uses MD5 authentication for router authenticity.  Troubleshooting EIGRP requires resolving link, neighbor, redistribution, and routing issues.  The following commands help you troubleshoot EIGRP issues: show ip eigrp neighbor, show ip eigrp topology, show ip eigrp interface, and show ip route. © 2007 Cisco Systems, Inc. All rights reserved. ICND2 v1.0—5-2 . routing issues.  The following commands help you troubleshoot EIGRP issues: show ip eigrp neighbor, show ip eigrp topology, show ip eigrp interface, and show ip route. © 2007 Cisco Systems, Inc successor, for fast convergence.  EIGRP supports unequal-cost load balancing.  EIGRP uses MD5 authentication for router authenticity.  Troubleshooting EIGRP requires resolving link, neighbor,. rights reserved. ICND2 v1.0—5-1 Module Summary  EIGRP is a classless routing protocol that supports VLSM.  Path selection is based upon several factors.  EIGRP keeps a next-best alternative path,