ACA-Cloud1 Exam Dumps : ACA Cloud Computing Associate

 Alibaba Cloud CDN can directly accelerate the access to the files stored in OSS and reduce OSS traffic costs. Alibaba Cloud CDN is a global network of points of presence (POPs) that are distributed across the globe. Alibaba Cloud CDN serves to reduce back-to-origin traffic. This in turn prevents network congestion and reduces latency. If you use Alibaba Cloud CDN to accelerate access to OSS, you can benefit from the following advantages1:

• Improved user experience: Alibaba Cloud CDN caches the files stored in OSS to the POPs that are nearest to the users. This reduces the distance that the files need to travel and improves the access speed and user experience.
• Reduced OSS traffic costs: Alibaba Cloud CDN reduces the number of requests that are sent to OSS. This reduces the OSS traffic costs and the load on the OSS servers.
• Enhanced security: Alibaba Cloud CDN supports HTTPS secure acceleration and anti-leech protection. This ensures the security and integrity of the files stored in OSS. References: Use Alibaba Cloud CDN to accelerate access to OSS

A large shopping mall deploys a new video surveillance system. The five-floor building in which the mall is located installed 35 HD cameras to monitor the major exits. The surveillance system is deployed on an ECS instance, which has four 2 TB data disks to store video data.

However, video data grows rapidly and the engineers find that the ECS will run out of storage space within 2 weeks.

In this case, OSS is thought to be the best solution for addressing the storage challenge while ensuring quick access to historical video data when needed. OSS is a cloud-based object storage service that provides massive, secure, low-cost, and highly reliable storage for unstructured data such as images, videos, and documents. OSS can store any amount of data and scale up or down on demand. OSS also supports direct video stream storage capabilities, removing the need for a video segmentation cluster. OSS can be accessed through RESTful APIs, SDKs, or web consoles, and can be integrated with other Alibaba Cloud services such as CDN, ECS, and SLB. OSS provides various storage classes for different data storage scenarios, from hot data storage to cold data storage. For video surveillance data, the Infrequent Access (IA) or Archive storage classes can be used to reduce the storage cost while maintaining high data durability and availability123. References: 1: Alibaba Cloud Multimedia Solutions | Video Monitoring & Surveillance1 2: Overview - Object Storage Service - Alibaba Cloud2 3: OSS Concepts - Alibaba Object Storage Service Course - Cloud Academy

 = A is the correct answer because the memory size of an ECS instance is determined by the instance type, and it cannot be changed independently. If you want to change the memory size of an ECS instance, you must change the instance type to another one that has a different memory size12

B, C, and D are incorrect answers because the system disk size, data disk size, and number of data disks of an ECS instance can be changed without changing the instance type. You can use the ECS console or API to resize the system disk or data disks of an ECS instance, or add or remove data disks from an ECS instance3456

References: 1: Overview of instance families 2: Change the instance type 3: Resize disks 4: Resize a disk 5: Attach or detach data disks 6: Attach or detach a data disk