What is an essential characteristic of OpenFlow?

OpenFlow is a foundational technology in software-defined networking (SDN) that enables the separation of the control layer and the data layer in network devices. Its essential characteristic lies in its ability to allow network administrators to control network traffic through programmable flows.

By using OpenFlow, administrators can define how packets should be processed or forwarded based on various criteria, such as source and destination IP addresses or port numbers. This programmability means that network policies and behaviors can be dynamically adjusted without needing to physically reconfigure devices.

In essence, OpenFlow provides a protocol for communication between the control plane, which makes decisions about where traffic is sent, and the data plane, which forwards traffic to its destination. This greater control and flexibility is what makes OpenFlow a critical component for modern network architectures, enabling more efficient resource utilization, quick policy changes, and the implementation of innovative network services.