(I) Classification of Billing Modes

Currently, eSurfing Cloud Distributed Message Service (Kafka) provides two billing modes: subscription (annual and monthly) and pay-as-you-go.

(1) Subscription

You can subscribe resources by month or by year. This offers a larger discount than the pay-as-you-go mode, and is recommended for long-term users. The fees are billed based on your subscription cycle.

(2) Pay-as-you-go

Pay-as-you-go billing is based on the billing cycle of the resources. When the billing cycle is reached, the system generates a bill and charges you accordingly. If your account balance is insufficient, the resources enter the grace period. If the payment is not completed during the grace period, the resources are stopped and reclaimed.

(II) The following table describes the differences between the two modes.

Billing Mode	Yearly/Monthly subscription	Pay-As-You-Go
Payment Methods	Prepaid and billed by your subscription cycle.	Postpaid and billed by the service duration.
Billing Cycle	Billed based on your subscription cycle.	Billed by hour.
Instance Upgrade	Scale-up is supported. The new data takes effect after the ticket is completed. The service is not available when the ticket is being carried out. Scale-down is not supported.	Scale-up is supported. The new data takes effect after the ticket is completed. The service is not available when the ticket is being carried out. Scale-down is not supported.
Changing Billing Mode	Can be changed to pay-as-you-go.	Can be changed to annual/monthly subscription.
Change Specification	Instance type can be changed.	Instance type can be changed.
Application Scenarios	This mode is ideal when you can estimate the resource usage period. The price is more favorable than that of the pay-as-you-go billing mode. This mode is recommended for long-term users.	This mode is ideal when you want more flexibility and control over resource usage. The service can be enabled and disabled anytime.

(III) Changing Billing Mode

eSurfing Cloud DMS (Kafka) supports billing mode changes. For more information, seeBilling Conversion.