Knative Serving uses an Ingress controller to serve all incoming traffic. This package configures Knative Serving with Contour. Make sure you install the Contour package before installing Knative Serving.
Two configurations are supported: one Contour instance used for both external and internal services, or two separate instances. Either way, you're required to specify the namespace where to find the Contour instance to use in each case.
ingress:
contour:
external:
namespace: projectcontour
internal:
namespace: projectcontour
For more information, check the Knative Serving documentation about installing a networking layer.