internal organization of the network layer (OSI) (IONL)

Internal Organization of the Network Layer (IONL) is the OSI standard for the detailed architecture of the network layer. IONL divides the network layer into three sublayers: Subnetwork Access, Subnetwork-Dependent and Subnetwork Independent.

The Subnetwork Access sublayer provides an interface through which data can be transferred across the subnetwork and the network. The Subnetwork Dependent sublayer assumes a specific network architecture, and the Subnetwork Independent sublayer supports the Internetworking of the layers above it.