What is an accurate description of redundancy?
configuring a router with a complete MAC address database to ensure that all frames can be forwarded to the correct destination
configuring a switch with proper security to ensure that all traffic forwarded through an interface is filtered
designing a network to use multiple paths between switches to ensure there is no single point of failure
designing a network to use multiple virtual devices to ensure that all traffic uses the best path through the internetwork
The Correct Answer And Explanation is:
Correct Answer:
Designing a network to use multiple paths between switches to ensure there is no single point of failure
Explanation:
Redundancy in networking refers to the inclusion of additional or alternative devices, equipment, paths, or systems that take over in the event of a failure of the primary components. The goal is to ensure network reliability and continuous availability of services. Redundancy eliminates or reduces the impact of failures, providing a fault-tolerant environment where downtime is minimized or avoided.
In the context of the correct answer, “designing a network to use multiple paths between switches to ensure there is no single point of failure” accurately reflects this principle. By having multiple paths, if one path (or switch, or link) fails, the data can still travel through another available route. This is a fundamental concept in network design, especially in enterprise networks, data centers, and cloud infrastructures.
One of the key technologies that support this is Spanning Tree Protocol (STP). STP is used in Layer 2 switching environments to prevent loops while also allowing redundant links to be available for failover. Similarly, in Layer 3 networks, routing protocols like OSPF, EIGRP, and BGP support path redundancy by selecting the best available route and recalculating paths when a failure is detected.
Let’s contrast the incorrect options:
- MAC address database on a router: Routers forward packets using IP addresses, not MAC addresses. This option is inaccurate and not related to redundancy.
- Security filtering on switches: This relates to access control or traffic management, not redundancy.
- Multiple virtual devices for best path: This may refer to load balancing, which optimizes traffic but does not directly address fault tolerance through multiple physical paths.
In summary, redundancy is all about reliability and fault tolerance, and using multiple paths between switches effectively ensures that no single point of failure can bring down the network.