Do I need to configure a Data Transfer Plan after purchasing it?

No.

After you purchase a Data Transfer Plan, the IPv4 traffic generated by pay-by-data-transfer Elastic Compute Service (ECS) instances, Elastic IP addresses, Server Load Balancer (SLB) instances, and Internet Shared Bandwidth instances are automatically deducted from the plan.

Does a Data Transfer Plan affect the peak bandwidth of cloud products?

No. A Data Transfer Plan is a resource package product and does not affect the peak bandwidth of cloud products.

Is traffic first deducted from the Data Transfer Plans that are purchased earlier?

No.

Traffic is deducted from Data Transfer Plans sequentially based on expiration time of the plans, that is, Data Transfer Plans that expire earlier are used first to cover the traffic usage. For example, if you have purchased two Data Transfer Plans, one expires on June 1, 2017, the other one expires on February 1, 2017. The Data Transfer Plan that expires on February 1, 2017 is first used to cover the traffic usage because it expires earlier than the other one.
Note If two Data Transfer Plans expire at the same time, traffic is first deducted from the one that is purchased earlier.

Can traffic generated by cloud products in regions not included on the purchase page be deducted from Data Transfer Plans?

No.

If a region is not displayed on the purchase page, traffic generated by cloud products in the region cannot be deducted from Data Transfer Plans.

Can traffic generated by pay-by-bandwidth cloud products be deducted from Data Transfer Plans?

No.

Data Transfer Plans can only be used to cover the IPv4 traffic generated by ECS instances, Elastic IP addresses, SLB instances, and Internet Shared Bandwidth instances that incur fees based on the pay-by-data-transfer basis.