HP-UX VLAN Administrator's Guide, February 2007

1 Introduction
This chapter provides an introduction to and technical overview of HP-UX Virtual LANs (VLANs).
It addresses the following topics:
• “Overview of VLANs” (page 13)
• “Features and Benefits of HP-UX VLANs” (page 23)
• “Administrative Methods for Managing HP-UX VLANs” (page 24)
• “Configuration and Administration Tasks” (page 25)
• “HP-UX VLAN Attributes” (page 25)
• “Using VLANs with HP Serviceguard” (page 27)
• “Unsupported Functionality” (page 28)
• “Hardware and Software Requirements” (page 28)
Overview of VLANs
This section provides an overview of VLANs.
For more information, including a customer implementation example, see the white paper HP-UX
VLAN: Planning and Implementing VLANs with HP-UX, available at:
http://www.docs.hp.com/en/netcom.html#Virtual%20Lan.
What Is a VLAN?
A virtual LAN (VLAN) is a logical (virtual) network segment that can span multiple physical
network segments. VLAN technology provides a means for separating logical network connectivity
from physical connectivity. More specifically, VLAN technology can be used to divide a physical
LAN into multiple logical LAN segments or broadcast domains.
The advantages of VLANs include:
• VLANs provide traffic isolation among the logical LAN segments, which leads to enhanced
security.
• VLANs reduce broadcast and multicast traffic, which leads to improved network
performance.
• VLANs can be used to implement a software patch panel for improved network
manageability. Because the physical location of an end station does not define its LAN
boundary you can change the network view simply by reconfiguring the VLAN membership;
a physical move is not required.
For example, using VLANs, you can group switched network and end stations by various
combinations, including the following:
• Department, such as engineering and manufacturing
• Type of user, such as power users or those with special needs
• Application
• Project
• Other
As shown in Figure 1-1 you do not have to group switched network and end stations by physical
location.
Overview of VLANs 13