| A | B |
|---|
| autonomous system | A set of routers running the same routing protocol under a single realm of control and authority. |
| feasibility condition | A condition under which, for a route to be considered a backup route, the reported distance received for that route must be less than the feasible distance calculated locally. This logic guarantees a loop-free path. |
| feasible distance | The metric value for the lowest-metric path to reach a destination. |
| feasibility successor | A route that satisfies the feasibility condition and is maintained as a backup route. |
| hello packets | Packets that are sent out at periodic interval to detect neighbors for establishing adjacency and ensuring that neighbors are still available. |
| hello timer | The amount of time between the advertisement of hello packets and when they are sent out an interface. |
| K vlaues | Values that EIGRP uses to calculate the best path. |
| reported distance | The distance reported by a router to reach a prefix. The reported distance value is the feasible distance for the advertising router. |
| successor | The first next-hop router for the successor route. |
| successor route | The route with the lowest path metric to reach a destination. |
| summarization | A method of reducing a routing table by advertising a less specific network prefix in lieu of multiple more specific network prefixes. |
| topology table | A table used by EIGRP that maintains all network prefixes, advertising EIGRP neighbors for prefixes and path metrics for calculating the best path. |
| variance value | The feasible distance (FD) for a route multiplied by the EIGRP variance multiplier. Any feasible successor’s FD with a metric below the EIGRP variance value is installed into the RIB. |
| wide metric | A new method of advertising and identifying interface speeds and delay to account for higher-bandwidth interfaces (20 Gbps and higher). |
