Overview

CFW provides two billing modes, yearly/monthly and pay-per-use billing, to meet requirements in different scenarios.

Yearly/Monthly billing is a prepaid mode in which you pay for the service before using it. Your bill is settled based on the required period. The longer the subscription term, the bigger the discount. Yearly/Monthly billing is a good option for long-term, stable services.
Pay-per-use is a postpaid billing mode. You pay as you go and just pay for what you use. The CFW usage is calculated by the second but billed every hour. With the pay-per-use billing mode, you can easily adapt to resource requirement changes, reducing the risk of over-provisioning of resources or lacking capacity. In this mode, there are no upfront commitments required. Pay-per-use billing is a good option for scenarios where there are sudden traffic bursts, such as e-commerce promotions.

Table 1 lists the details about the yearly/monthly billing modes.

**Table 1** Billing mode
Billing Mode	Yearly/Monthly	Pay-per-use
Payment	Prepaid Billed by the subscription term you purchase	Postpaid Calculated based on the actual usage duration and traffic processed by the CFW.
Billing Period	Billed by the subscription term you purchase	Billed by the second and settled by the hour
Billing Item	Edition Number of extended packages (added EIP protection capacity, added peak traffic protection capacity, and added VPCs)	Edition Usage duration
Changing the Billing Mode	The billing mode cannot be changed to pay-per-use.	The billing mode cannot be changed to yearly/monthly.
Changing the Specifications	Service version specifications can be changed.	N/A
Application Scenarios	It is suitable when your resource usage duration is predictable because you can pay less by using longer. It is more favorable than pay-per-use billing mode. Recommended for resources expected to be in use long-term.	Recommended when the resource demands are likely to fluctuate and you want more flexibility.