notes: RIP Split-horizon, RIP triggered

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Split-Horizon, RIP Triggered
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- RIP employs split-horizon with poison reverse and triggered updates.

Split-Horizon

- Updates received in an interface will not be sent out of the same interface.
- Might be undesirable on partial mesh NBMA networks like multipoint interfaces.
- Is enabled for all interfaces by default, except main physical interfaces in frame-relay which has it disabled by default.

RIP triggered

- A triggered update occurs whenever the metric for a route is changed and, unlike regularly scheduled updates, includes only the entries that have changed.
- The receiving router does not reset its update timer when a triggered update is received.
- The command "ip rip triggered" enables the triggered extensions of RIP. It is needed on both sides of a link.
- Route table updates are minimized to include only the initial exchange of route tables and updates when changes to the route tables occur.
- The triggered state goes from DOWN, through INIT and LOADING, to FULL.
- Should only be configured on a point-to-point serial link.

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COMMANDS
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1. Enabled triggered updates on interface level.

ip rip triggered

- Only available on serial link, if both sides are enabled

2. Disables split-horizon

no ip split-horizon

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verification
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1. show ip protocols