Prior to this launch, when using an instance ID as a target, an EC2 instance could only receive traffic from the load balancer on its primary IP address and primary network interface. This limits hosting multiple applications on the same instance where each application requires different IP address, network interface, or security group. Using IP addresses as targets removes this limitation as the load balancer can route to multiple network interfaces on the same instance. Load balancing using IP addresses also provides flexibility with microservice based architectures, where each application target can now use a known port instead of a random port simplifying inter-application communication. This feature also enables load balancing to your on-premises resources thereby supporting hybrid architectures.