Cloud Firewall's elastic traffic billing handles bandwidth spikes beyond your subscription plan by automatically scaling up and billing only for the excess traffic you use. Your base subscription covers normal traffic at a fixed monthly cost; any excess is charged at 0.06 USD/GB on a pay-as-you-go basis.
When traffic stays within your purchased bandwidth, no elastic charges apply.
Use cases
Periodic daily peaks: Traffic spikes during fixed windows, such as peak transactions from 09:00 to 09:30 each day.
Occasional minor spikes: Brief, unexpected increases caused by business or interface adjustments.
Promotional and event surges: Traffic surges during events such as the Double 11 Shopping Festival or security drills.
Billing
Starting October 15, 2025, Cloud Firewall introduced Billing Method 2.0. New users are on Billing Method 2.0 by default; existing users continue with Billing Method 1.0. The two methods differ in how elastic traffic is enabled and calculated.
Billing method comparison
| Billing Method 2.0 | Billing Method 1.0 | |
|---|---|---|
| Status | Enabled by default; cannot be disabled | Disabled by default; enable as needed |
| Price | 0.06 USD/GB | 0.06 USD/GB |
| What counts as excess | Total excess traffic across all borders | Excess outbound + inbound traffic across Internet Border, NAT Border, and VPC Border |
| Free quota | None | 10 GB/day shared across all borders (after enabling) |
| Elastic bandwidth limit | 10 Gbps | 10 Gbps |
| Billing cycle | Billed the next day | Billed the next day |
Billing Method 2.0 details
The charge is: excess traffic (GB) × 0.06 USD/GB.
To monitor usage, go to System Settings > Alert and configure an Elastic Billing Alert. The alert triggers when peak bandwidth reaches a specified percentage of your purchased bandwidth.
For custom bandwidth limits above 10 Gbps, contact your business manager or architect.
Billing Method 1.0 details
If elastic traffic billing is not enabled and your bandwidth exceeds the purchased limit, your Service-Level Agreement (SLA) is not guaranteed. Excess traffic may trigger downgrade rules, including security feature failures, firewall shutdowns for top assets with excess traffic, rate limiting, or packet loss.
The charge is: (excess outbound Internet Border + excess inbound Internet Border + excess outbound NAT Border + excess outbound VPC Border + excess inbound VPC Border) × 0.06 USD/GB.
After enabling, you receive 10 GB of free elastic traffic per day, shared across all borders.
To enable elastic traffic billing:
Go to the Overview page and click Upgrade.
Set Elastic Traffic Processing Capacity to Yes.
The change takes effect immediately. You can enable it only once per day.
To monitor usage, go to System Settings > Alert and configure an Elastic Billing Alert.
To reduce costs further, use elastic traffic billing with pay-as-you-go savings plans.
Billing example
This example compares the cost of handling excess bandwidth through a permanent upgrade versus elastic traffic billing.
Scenario: A company has Internet Border protection enabled with 30 Mbps of purchased bandwidth. Normal daily peak is 10-20 Mbps, with occasional 10-minute bursts to 100 Mbps. Over one month:
Excess bandwidth: 70 Mbps
Total excess traffic: 200 GB
| Approach | Calculation | Monthly cost |
|---|---|---|
| Permanent bandwidth scale-out | 70 Mbps × 7 USD/Mbps/month (standard bandwidth unit price) | 490 USD |
| Elastic traffic billing | 200 GB × 0.06 USD/GB | 12 USD |
For short, infrequent bursts, elastic traffic billing costs far less than permanently upgrading your subscription bandwidth.