What is the purpose of Virtual Network Interface Cards (VNICs) in OCI?

Virtual Network Interface Cards (VNICs) in Oracle Cloud Infrastructure (OCI) serve as the primary means for connecting compute instances to virtual networks. The creation of VNICs allows compute instances to communicate over the network by associating them with specific subnets. Each VNIC can be configured with its own private and public IP addresses, enabling both internal and external network connectivity as required by the instance.

By managing network traffic, VNICs handle the ingress and egress of data packets for the compute instances, thus playing a crucial role in ensuring efficient communication within the OCI infrastructure. This ability to connect to subnets and manage network traffic underpins the functioning of cloud applications and services deployed on OCI.

Additionally, while VNICs can connect compute instances to the internet via public IP addresses and enable connectivity to other OCI services, their primary purpose relates to managing overall network traffic and facilitating connections within virtual networks. This is what solidifies the role of VNICs in OCI's networking architecture.