VoIP over VPN Design and Security Considerations

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Application Note
LANs and VLANs
A Simplified Tutorial
Version 3.0
Avaya Labs
May 2002
COMPAS ID 90947
1Companion document
•
IP Addressing: A Simplified Tutorial
COMPAS ID 92962
2Introduction
As the name implies, the purpose of this presentation is to
provide a simplified tutorial on local area networks (LANs) and virtual
local area networks (VLANs).
The instructions and terminology used in this presentation attempt
to comply with industry practices and written standards. They represent
the generally accepted implementations of the written standards.
It is important to understand that written standards are sometimes
ambiguous, and are thus implemented differently among various
vendors. This tutorial seeks to balance between the two and does not
rely solely on written standards or specific implementations.
All IP addresses and numbering schemes in this tutorial are
hypothetical, and used for illustration purposes.
3First, the basics
4OSI and TCP/IP
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•
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