K8TRE - base infrastructure options: Load balancers

[manics]

All public clouds provide load balancer. This may not be the case for on-prem clusters. We should describe where load balancers are required in K8TRE. For example, if the load balancer only provides HTTP/HTTPS access to an ingress controller which handles multiply endpoints there are alternatives to a load balancer controller and we could rename this infrastructure option to "external ingress access". If we intend to spin up multiple services each with an independent load balancer this complicates things for on-prem systems as well as increasing cloud costs.

[manics]

AWS:

• The AWS load balancer controller provisions elastic load balancers. These can be Application load balancers (layer 7, effectively an ingress controller) or Network load balancers (layer 4). From a cost perspective it is desirable to minimise the number of load- balancers as they are individually charged for.

[t-young31]

+1 for NLB for that e2e TLS goodness