networking: Rename to legacy networking

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diff --git a/legacy-networking/network_task_structure.rst b/legacy-networking/network_task_structure.rst
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+.. SPDX-License-Identifier: CC-BY-SA-4.0
+
+.. COMMENT: Written by Eric Norum
+.. Copyright (C) 1988, 2002 On-Line Applications Research Corporation (OAR)
+
+Network Task Structure and Data Flow
+####################################
+
+A schematic diagram of the tasks and message *mbuf* queues in a simple RTEMS
+networking application is shown in the following figure:
+
+.. figure:: ../images/networking/networkflow.png
+  :align: center
+  :alt: Network Flow
+
+The transmit task for each network interface is normally blocked waiting for a
+packet to arrive in the transmit queue.  Once a packet arrives, the transmit
+task may block waiting for an event from the transmit interrupt handler.  The
+transmit interrupt handler sends an RTEMS event to the transmit task to
+indicate that transmit hardware resources have become available.
+
+The receive task for each network interface is normally blocked waiting for an
+event from the receive interrupt handler.  When this event is received the
+receive task reads the packet and forwards it to the network stack for
+subsequent processing by the network task.
+
+The network task processes incoming packets and takes care of timed operations
+such as handling TCP timeouts and aging and removing routing table entries.
+
+The 'Network code' contains routines which may run in the context of the user
+application tasks, the interface receive task or the network task.  A network
+semaphore ensures that the data structures manipulated by the network code
+remain consistent.