Shared load balancers support only IPv4 networks. Dedicated load balancers support both IPv4 and IPv6 networks.
When a client communicates with a dedicated network load balancer using an IPv6 address, the load balancer must communicate with backend servers using an IPv6 address. When a client communicates with an application dedicated load balancer using an IPv6 address, the load balancer must communicate with backend servers using an IPv4 address.