Appendix A. Internet Resources and More

Chapter 1

A concise but easy explanation of the OSI model can be found in Wikipedia:

Available OSI protocols:

The Internet Protocol (IP):

A basic introduction to IPsec:


A very good overview on Layer 2 Forwarding (L2F) can be found here:

The Internet Engineering Task Force details can be found at:

Read the IPsec article in Wikipedia:

The Linux ...

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