Network traffic limits on EC2 instances

An instance receives the maximum number of network I/O credits at launch. If the instance exhausts its network I/O credits, it returns to its baseline bandwidth. A running instance earns network I/O credits whenever it uses less network bandwidth than its baseline bandwidth. A stopped instance does not earn network I/O credits. Instance burst is on a best effort basis, even when the instance has credits available, as burst bandwidth is a shared resource.

You can find more information at AWS official documentation .

Specific to c6g instance, you can find the baseline network performance here at https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/compute-optimized-instances.html#compute-network-performance

If you would like to get much higher baseline performance, then look for the instance type that ends with letter "n". For example C5n, M5n, C6gn, etc