Implementing and Operating Cisco Enterprise Network Core Technologies (ENCOR) v1.2InfrastructureMedium
A network engineer is troubleshooting an intermittent connectivity issue for several end-users connected to a Cisco Catalyst switch. The issue appears to be related to excessive broadcast traffic causing network slowdowns. The engineer suspects a misconfigured device or a loop creating a broadcast storm. Which Layer 2 feature can be configured on the switch ports to prevent excessive broadcast traffic from consuming all available bandwidth?
- ABPDU Guard
- BStorm Control
- CDHCP Snooping
- DPort Security
Show answer & explanationAnswer & explanation
Correct answer: B. Storm Control
Storm Control is a Layer 2 feature that monitors incoming broadcast, multicast, and unicast traffic on an interface and, when the configured threshold is exceeded, suppresses the excess traffic. This prevents excessive traffic from consuming switch resources and causing network outages, making it ideal for mitigating broadcast storms.
Why the other options are wrong
- A. BPDU Guard is a Spanning Tree Protocol (STP) feature that shuts down a port if it receives a BPDU, typically used on edge ports to prevent loops, but not for general broadcast storm mitigation from end devices.
- C. DHCP Snooping is a security feature that prevents unauthorized DHCP servers and ensures valid DHCP leases, not for broadcast storm prevention.
- D. Port Security restricts the number of MAC addresses allowed on a port, preventing unauthorized devices, but does not directly control broadcast traffic volume.
Storm Control
A Layer 2 feature that prevents excessive broadcast, multicast, or unicast traffic from consuming network resources by suppressing traffic that exceeds a configured threshold on an interface.
- Monitors incoming traffic on a port.
- Suppresses traffic (broadcast, multicast, unicast) exceeding a threshold.
- Prevents broadcast storms and network degradation.
- Can be configured with different actions (shutdown, drop, trap).
Memory trick: Layer 2: Protecting the local network from bad actors and storms.