HP UX 11i v2 Networking Software manual Data Link Layer, Service Interface

Introduction to DLPI

The Data Link Layer

The Data Link Layer

The data link layer (layer 2 in the OSI Reference Model) is responsible for the transmission and error-free delivery of bits of information over a physical communications medium. The model defines networking functionality at several layers and service providers between the layers.

A model of the data link layer is presented here to describe concepts that are used throughout this guide. It is described in terms of an interface architecture, as well as addressing concepts needed to identify different components of that architecture. The description of the model assumes familiarity with the OSI Reference Model.

The Service Interface

Each layer of the OSI Reference Model has two standards:

•one that defines the services provided by the layer.

•one that defines the protocol through which layer services are provided.

DLPI is an implementation of the first type of standard. It specifies an interface to the services of the data link layer. Figure 1-1 illustrates how DLPI performs this function.

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