300-415 Question 281
Single answerA company has deployed Cisco SD-WAN across its branches to improve WAN performance. The network administrator notices that applications with high latency sensitivity, such as database replication over TCP, are experiencing performance degradation. How can the administrator use Cisco SD-WAN TCP optimization features to address this issue?
- A
Enable TCP optimization on the vManage controller to apply globally across all sites.
- B
Configure TCP optimization on the vEdge routers to reduce retransmissions and improve throughput.
- C
Enable TCP optimization on the transport-side interface of the vEdge router to leverage WAN optimization.
- D
Configure TCP optimization policies specific to the affected applications at the application-level policy.
Show answer and explanation
Correct answer: B
Explanation
TCP optimization in Cisco SD-WAN is a feature implemented on the vEdge routers to enhance TCP performance by reducing retransmissions, improving throughput, and minimizing latency. This includes techniques like TCP flow control and congestion window adjustments. The administrator must configure TCP optimization on the vEdge routers to address performance issues for applications that rely heavily on TCP.
- A. Incorrect.
TCP optimization cannot be enabled on the vManage controller as it functions primarily for management, not data plane operations. Optimization must be configured on the data plane devices, such as vEdge routers.
- B. Correct.
Configuring TCP optimization on the vEdge routers is the correct approach, as these routers handle data plane traffic and can apply optimization techniques like congestion control, window scaling, and retransmission management to improve TCP performance.
- C. Incorrect.
Enabling TCP optimization on the transport-side interface alone is not sufficient. TCP optimization must be configured at the system level on the vEdge router to have a meaningful impact on TCP performance.
- D. Incorrect.
While application-level policies can prioritize traffic, TCP optimization specifically targets improving TCP protocol performance and is not configured at the application policy level.