• Split horizon -the routing switch does not advertise a route on the same interface as the one on which the
routing switch learned the route.
• Poison reverse - the routing switch assigns a cost of 16 ("infinity" or "unreachable") to a route before
advertising it on the same interface as the one on which the routing switch learned the route. This is the
default.
These loop prevention methods are configurable on an individual VLAN interface basis.
NOTE:
These methods are in addition to RIP's maximum valid route cost of 15.
Chapter 8 Routing Information Protocol (RIP)
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