switch endpointSlice.AddressType {
	case discovery.AddressTypeIPv4:
		proxier.ipv4Proxier.OnEndpointSliceAdd(endpointSlice)
	case discovery.AddressTypeIPv6:
		proxier.ipv6Proxier.OnEndpointSliceAdd(endpointSlice)
	default:
		klog.ErrorS(nil, "EndpointSlice address type not supported", "addressType", endpointSlice.AddressType)
	}
}

				ObjectMeta:  standardMeta,
				AddressType: discovery.AddressType("IP"),
			},
			newEndpointSlice: &discovery.EndpointSlice{
				ObjectMeta:  standardMeta,
				AddressType: discovery.AddressType("IP"),
			},
		},
		"valid and identical slices with different address types": {
			oldEndpointSlice: &discovery.EndpointSlice{
				ObjectMeta:  standardMeta,
				AddressType: discovery.AddressType("other"),
			},

}

func getAddressType(address string) *discovery.AddressType {
	ip := netutils.ParseIPSloppy(address)
	if ip == nil {
		return nil
	}
	addressType := discovery.AddressTypeIPv4
	if ip.To4() == nil {
		addressType = discovery.AddressTypeIPv6
	}
	return &addressType
}

// newEndpointSlice returns an EndpointSlice generated from an Endpoints
// resource, ports, and address type.

	// +optional
	// +listType=atomic
	Ports []EndpointPort
}

// AddressType represents the type of address referred to by an endpoint.
type AddressType string

const (
	// AddressTypeIPv4 represents an IPv4 Address.
	AddressTypeIPv4 = AddressType(api.IPv4Protocol)
	// AddressTypeIPv6 represents an IPv6 Address.
	AddressTypeIPv6 = AddressType(api.IPv6Protocol)
	// AddressTypeFQDN represents a FQDN.

	}
	return names
}

// warnOnDeprecatedAddressType returns a warning for endpointslices with FQDN AddressType
func warnOnDeprecatedAddressType(addressType discovery.AddressType) []string {
	if addressType == discovery.AddressTypeFQDN {
		return []string{fmt.Sprintf("%s: FQDN endpoints are deprecated", field.NewPath("spec").Child("addressType"))}
	}
	return nil

	// * IPv6: Represents an IPv6 Address.
	// * FQDN: Represents a Fully Qualified Domain Name.
	AddressType AddressType `json:"addressType" protobuf:"bytes,4,rep,name=addressType"`

	// endpoints is a list of unique endpoints in this slice. Each slice may
	// include a maximum of 1000 endpoints.
	// +listType=atomic
	Endpoints []Endpoint `json:"endpoints" protobuf:"bytes,2,rep,name=endpoints"`

			endpointSlice.AddressType = discovery.AddressTypeIPv6
		}

		endpointSlice.Endpoints = append(endpointSlice.Endpoints, getEndpointsFromAddresses(subset.Addresses, endpointSlice.AddressType, true)...)
		endpointSlice.Endpoints = append(endpointSlice.Endpoints, getEndpointsFromAddresses(subset.NotReadyAddresses, endpointSlice.AddressType, false)...)
	}

	return endpointSlice
}

	// DebugType requests debug info from istio, a secured implementation for istio debug interface.
	DebugType                 = "istio.io/debug"
	BootstrapType             = APITypePrefix + "envoy.config.bootstrap.v3.Bootstrap"
	AddressType               = APITypePrefix + "istio.workload.Address"
	WorkloadType              = APITypePrefix + "istio.workload.Workload"
	WorkloadAuthorizationType = APITypePrefix + "istio.security.Authorization"
)

	// * IPv6: Represents an IPv6 Address.
	// * FQDN: Represents a Fully Qualified Domain Name.
	AddressType AddressType `json:"addressType" protobuf:"bytes,4,rep,name=addressType"`

	// endpoints is a list of unique endpoints in this slice. Each slice may
	// include a maximum of 1000 endpoints.
	// +listType=atomic
	Endpoints []Endpoint `json:"endpoints" protobuf:"bytes,2,rep,name=endpoints"`

// types.
type multiAddrTypePortMapKey map[discovery.AddressType]addrTypePortMapKey

// initPorts initializes ports for a subset and address type and returns the
// corresponding addrTypePortMapKey.
func (d *desiredCalc) initPorts(subsetPorts []v1.EndpointPort) multiAddrTypePortMapKey {
	endpointPorts := epPortsToEpsPorts(subsetPorts)
	addrTypes := []discovery.AddressType{discovery.AddressTypeIPv4, discovery.AddressTypeIPv6}