ASN Blocking

Configure ASN Blocking to reject requests from specified autonomous systems.

Block requests from specified autonomous systems by configuring their Autonomous System Numbers (ASNs).

ASN Blocking evaluates the ASN associated with each incoming request and blocks traffic from configured ASNs. Blocked requests receive a 403 response at the CDN edge before cache lookup or origin forwarding.

ASN Blocking is configured for CDN Resources in the Medianova Control Panel.

Configure ASN Blocking

1

Open Security

Open the CDN Resource that you want to configure and select Security - Geo blocking.

2

Enable ASN Blocking

Turn on ASN Blocking.

3

Add Blocked ASNs

Under Blocked ASN, enter the ASN that you want to block and select Add.

ASN numbers can be entered with or without the AS prefix. For example:

• AS13335

• 13335

Add additional ASNs as required.

4

Save the Configuration

Select Save in the pending changes bar.

Review the pending changes and confirm the configuration.

How ASN Blocking Works

When ASN Blocking is enabled, the CDN evaluates the autonomous system number associated with each incoming request.

If the ASN is included in the blocked list:

• The request is rejected with an HTTP 403 response.

• The request is blocked at the CDN edge.

• Cache lookup is not performed.

• The request is not forwarded to the origin server.

Manage Blocked ASNs

Configured ASNs are displayed under Blocked ASNs.

You can remove an individual ASN from the list or select Clear all to remove all configured ASNs. Save the CDN Resource configuration after making changes.

Important Notes

• ASN Blocking uses a blocklist model. Only ASNs added to Blocked ASNs are rejected.

• ASN values can be entered with or without the AS prefix.

• Removing an ASN from the list allows it to stop being subject to this ASN-based block after the updated configuration is saved.

Related Concepts

• IP Restriction

• Geo Blocking

• Security