This variable specifies whether to send poison reverse updates on this interface. Poison reverse updates are used to prevent larger loops within the network by setting the metric (cost) of neighboring routes to infinity. This will prevent two-hop loops. By default, RIP uses a technique called split horizon to avoid routing loops and allow smaller update packets. Split horizon specifies that when a RIP update is sent out a particular network interface, it should not include routing information acquired over that same interface. Poison Reverse is a variation of the split horizon technique that specifies that all routes are included in an update out a particular interface, but that the metric is set to infinity for routes acquired over that interface. One drawback is that routing update packet sizes are increased when using poison reverse. Setting the value of this object to 'disable' prevents poison reverse updates, where 'enable' allows poison updates to be sent on this interface. The default value is 'disabled'.