ENA Express now supports 10 new instances: C6a.48xlarge, C6a.metal, M6a.48xlarge, M6a.metal, R6a.48xlarge, R6a.metal, x2idn.32xlarge, x2idn.metal, x2iedn.32xlarge, and x2iedn.metal. ENA Express is a networking feature that uses the AWS Scalable Reliable Datagram (SRD) protocol to improve network performance in two key ways: higher single flow bandwidth and lower tail latency for network traffic between EC2 instances. SRD is a proprietary protocol that delivers these improvements through advanced congestion control, multi-pathing, and packet reordering directly from the Nitro card.
Source:: Amazon AWS