Cisco Certified Network Associate (CCNA) Practice Exam

Which protocol can cause overload on a CPU of a managed device?

1. Netflow

2. WCCP

3. IP SLA

4. SNMP

The correct answer is: SNMP

The correct answer is SNMP (Simple Network Management Protocol). When a managed device, such as a router or switch, is configured to respond to SNMP polling requests from management systems, it can lead to CPU overload if the number of requests is high. This overload occurs because SNMP operates by polling the device for status and performance metrics, which can consume significant CPU resources, especially on devices with limited processing capacity or when configured to handle extensive management tasks. NetFlow, WCCP, and IP SLA serve different purposes. NetFlow is primarily used for traffic analysis and monitoring, which does have some resource implications but is generally optimized for performance. WCCP (Web Cache Communication Protocol) is utilized for redirecting web traffic for caching purposes, and while it requires some CPU resources, it doesn't typically cause the same level of overload as SNMP might. IP SLA (Internet Protocol Service Level Agreement) is designed to monitor the performance of network services and typically runs in a way that minimizes CPU usage. Thus, SNMP is the protocol most likely to be responsible for it if improperly configured or excessively polled, leading to potential strain on the device's CPU resources.