Cisco Certified Support Technician (CCST) NetworkingIP ConnectivityMedium
A network engineer is designing a routing solution for a network where fast convergence and support for unequal-cost load balancing are critical requirements. Which IP routing protocol is best suited for these requirements?
- ABGP
- BOSPF
- CRIPv2
- DEIGRP
Show answer & explanationAnswer & explanation
Correct answer: D. EIGRP
Enhanced Interior Gateway Routing Protocol (EIGRP) is known for its fast convergence, often attributed to its DUAL algorithm, and its ability to perform unequal-cost load balancing using the `variance` command. These features make it well-suited for scenarios requiring rapid adaptation to network changes and efficient use of all available paths.
Why the other options are wrong
- A. BGP is an Exterior Gateway Protocol (EGP) used for inter-autonomous system routing, not typically for fast convergence or unequal-cost load balancing within an enterprise.
- B. OSPF is a link-state protocol with faster convergence than RIP but only supports equal-cost load balancing by default.
- C. RIPv2 is a distance-vector protocol with slow convergence and only supports equal-cost load balancing.
EIGRP Features
Enhanced Interior Gateway Routing Protocol (EIGRP) is a Cisco proprietary advanced distance-vector routing protocol known for fast convergence, unequal-cost load balancing, and efficient use of bandwidth.
- Uses DUAL (Diffusing Update Algorithm) for fast convergence.
- Supports unequal-cost load balancing with the `variance` command.
- Classified as a hybrid routing protocol (advanced distance-vector).
Memory trick: EIGRP: Fast and Flexible Paths.