Introduction to NETGRAPH on FreeBSD Systems
Summary
FreeBSD’s NETGRAPH infrastructure can be understood as customizable “network plumbing”.
Its flexibility and the fact that this infrastructure runs in the kernel makes it an attractive enabling
technology where time-to-market, agility, and performance are important.
The goal of the tutorial is to become familiar with FreeBSD’s NETGRAPH framework and the
available NETGRAPH kernel modules. The participants will gain insight and understanding for
which projects lend themselves well to NETGRAPH solutions. A number of examples are shown
which can be used as a starting point for new NETGRAPH projects.
In the first part of the tutorial, the NETGRAPH nodes, hooks, and control messages are described
and the command syntax is explained via demonstrations on simple examples. Participants learn
how they can describe a network connection in terms of its underlying protocols and how to express
a solution using NETGRAPH terminology.
The second part of the tutorial investigates frequently used NETGRAPH nodes and shows how they
interconnect to create network protocols. More complex NETGRAPH examples including VLAN
bridges, UDP tunnels, and the Multi-link Point-to-Point daemon are described. Guidelines and
resources for developing custom NETGRAPH modules are surveyed.
Tutorial Outline
Since its introduction to FreeBSD 3.x over a decade ago, the NETGRAPH system is being
continuously maintained and developed by the community as can be seen by the constant addition
of new ng_* kernel modules supporting additional networking features. The tutorial is structured
along the following outline:
•
History and motivation
•
From TTY device driver to System V STREAMS
•
Transport Protocol Multiplexors and Graphs
•
NETGRAPH Platforms, Software Licensing
•
Evolution on FreeBSD
•
Important Reading Resources
•
How to build a NETGRAPH
•
Prerequisites
•
Creating Nodes
•
Connecting Nodes and Creating Edges
Extended abstract of tutorial and lecturer biography! Introduction to NETGRAPH on FreeBSD Systems
AsiaBSDCon on March 22-23, 2012 in Tokyo, Japan" Page 1 / 3
Dr
.
Adrian Steinmann, <ast@marabu.ch>
! V
ersion 2.5, February 2012
