Cisco Certified Support Technician (CCST) NetworkingIP ConnectivityMedium
A network engineer is troubleshooting an EIGRP routing issue. They suspect that the EIGRP metric calculation is incorrect, leading to suboptimal path selection. Which components are used by EIGRP to calculate its composite metric by default?
- ABandwidth, Delay, Reliability, and Load
- BBandwidth and Delay
- CBandwidth and Load
- DDelay, Reliability, and Hops
Show answer & explanationAnswer & explanation
Correct answer: B. Bandwidth and Delay
By default, EIGRP uses Bandwidth and Delay as the primary components to calculate its composite metric. Reliability and Load are also factors but are not used by default unless specifically configured.
Why the other options are wrong
- A. This option lists all potential components, but Reliability and Load are not used by default.
- C. This option is incomplete, as Delay is also a default component.
- D. Hops are not a direct component of the EIGRP composite metric; Delay and Reliability are, but Hops are not, and Bandwidth is missing.
EIGRP Composite Metric
EIGRP calculates a composite metric for path selection using several components, with Bandwidth and Delay being the default factors.
- Default components: Bandwidth and Delay.
- Optional components: Reliability and Load.
- Uses K-values (K1-K5) to weight these components.
- Lower metric values indicate a better path.
Memory trick: EIGRP's path choice depends on how fast and how long.