Dynamic Connections IP VPN support

Aggregate and advertise my RFC 1918 routes - Option 1 (default)

Option 1 is the ideal option if your cloud service provider has a restrictive BGP prefix limit like AWS or GCP and a majority of your prefixes are RFC 1918.

To reduce the number of prefixes sent to the cloud service provider, we automatically aggregate network prefixes according to the RFC 1918 standards.

We only advertise network RFC 1918 prefixes: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16.

Note: Aggregates are not injected into your routing tables.

Advertise all routes except those specified ‑ Option 2

Option 2 is the best option when you want to control which routes are advertised to the cloud service provider (CSP). Please check with your CSP to verify any BGP maximum prefix‑limits before selecting, as it could cause issues with your connection.

By default, the provider edge router advertises all your network prefixes except those that you append the block community to. If you would like to deny specific prefixes, please mark those prefixes in your routing table with the appropriate BGP community.

Blocking communities are assigned per CSP.

• AWS: 6745:8601
  
• Azure: 6745:8600
  
• Google: 6745:8604
  
• Oracle: 6745:8606

Deny all routes except those specified - Option 3

Option 3 is the best choice if your cloud service provider has a maximum prefix-limit and you need to reduce your advertised prefixes. Your network prefixes don’t fall under the option 1 RFC 1918 ranges.

It allows you to pick which prefixes to allow by specifying the aggregates below. Please note, aggregates are not injected into your routing tables.

You also have the flexibility with option 3 to advertise any of your network prefixes to the cloud provider by appending BGP cloud-allow community 6745:8610 to the prefix in your routing table (not below). This will allow advertisement to the cloud provider.