Configure Vlan Support - HP ProCurve 7000dl Series Basic Management And Configuration Manual

Configuring Ethernet Interfaces

Configure VLAN Support

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Configure VLAN Support
VLANs enable you to group users by logical function rather than physical
location. Creating VLANs on your network provides several advantages:
VLANs allow you to segment your network into smaller broadcast
domains. In networks that have large broadcast domains, broadcast
storms can disrupt network traffic.
VLANs enhance your network security. Because each VLAN is a separate
broadcast domain, members of a particular VLAN cannot "see" traffic
from other VLANs.
VLANs simplify network management. For example, you can use VLANs
to grant users access to network resources.
ProCurve Networking devices support the IEEE 802.1Q standard for VLAN
tagging. When you define a VLAN on an 802.1Q-compliant device, it inserts a
four-byte tag into the Ethernet frame. This tag identifies the packet's VLAN
membership. The 802.1Q tag contains:
the tag value, which identifies the data as a tag
the VLAN ID
As per the 802.1Q specification, the default tag value is 8100 (hexadecimal).
The VLAN ID is determined by the VLAN on which the packet is being
forwarded.
Figure 3-3 shows the format of Ethernet frames that contain the 802.1Q tag.
Because a VLAN tag is inserted into the Ethernet frame, it is called VLAN
tagging in a ProCurve environment. (In a Cisco environment, VLAN tagging
is referred to as VLAN trunking.)