Network Core Engine

Principle

The Net module defines a low-level network framework for embedded devices. This module allows you to manage connection (TCP)- or connectionless (UDP)-oriented protocols for client/server networking applications.

Functional Description

The Net library includes two sub-protocols:

  • UDP: a connectionless-oriented protocol that allows communication with the server or client side in a non-reliable way. No handshake mechanisms, no guarantee on delivery, and no order in packet sending.
  • TCP: a connection-oriented protocol that allows communication with the server or client side in a reliable way. Handshakes mechanism used, bytes ordered, and error checking performed upon delivery.

Dependencies

  • LLNET_CHANNEL_impl.h, LLNET_SOCKETCHANNEL_impl.h, LLNET_STREAMSOCKETCHANNEL_impl.h, LLNET_DATAGRAMSOCKETCHANNEL_impl.h, LLNET_DNS_impl.h, LLNET_NETWORKADDRESS_impl.h, LLNET_NETWORKINTERFACE_impl.h (see LLNET: Network).

Installation

Network is an additional module. In the platform configuration file, check NET to install this module. When checked, the properties file net > net.properties is required during platform creation to configure the module. This configuration step is used to customize the kind of TCP/IP native stack used and the Domain Name System (DNS) implementation.

The properties file must / can contain the following properties:

  • stack [optional, default value is “custom”]: Defines the kind of TCP/IP interface used in the C project.
    • custom: Select this configuration to make a “from scratch” implementation glue between the C Network Core Engine and the C project TCP/IP interface.
    • bsd: Select this configuration to use a BSD-like library helper to implement the glue between the C Network Core Engine and the C project TCP/IP interface. This property requires that the C project provides a TCP/IP native stack with a Berkeley Sockets API and a select mechanism.
  • dns [optional, default value is “native”]: Defines the kind of Domain Name System implementation used.
    • native: Select this configuration to implement the glue between the C Network Core Engine DNS part and the C project TCP/IP interface.
    • soft: Select this configuration if you want a software implementation of the DNS part. Only the IPs list of the DNS server must be provided by the C Network Core Engine glue.

Use

A classpath variable named NET-1.1 is available.

This library provides a set of options. Refer to the chapter Application Options which lists all available options.