HP (Hewlett-Packard) T1453-90001 Benutzerhandbuch
What are HP-UX VLANs?
HP-UX VLAN Tagging
Chapter 1
15
HP-UX VLAN Tagging
Network switches and end stations that know about VLANs are said to
be VLAN-aware. Network switches and end stations that can interpret
VLAN tags are said to be VLAN-tag-aware. HP-UX VLAN-tag-aware
end stations add VLAN tags to standard Ethernet frames--a process
called explicit tagging. A VLAN tag (Figure 1-2) identifies which
VLAN a data frame belongs to and enables traffic from more than one
VLAN to use the same switch or LAN card port (Figure 1-3).
be VLAN-aware. Network switches and end stations that can interpret
VLAN tags are said to be VLAN-tag-aware. HP-UX VLAN-tag-aware
end stations add VLAN tags to standard Ethernet frames--a process
called explicit tagging. A VLAN tag (Figure 1-2) identifies which
VLAN a data frame belongs to and enables traffic from more than one
VLAN to use the same switch or LAN card port (Figure 1-3).
When a VLAN-aware switch receives data from an end-station, the
switch determines where the data is to go and whether the VLAN ID
should be retained. If the data is to go to a device that can recognize the
VLAN tag, the VLAN tag is retained. If the data is to go to a device that
has no knowledge of VLANs (VLAN-unaware), the switch sends the
data without the VLAN tag.
switch determines where the data is to go and whether the VLAN ID
should be retained. If the data is to go to a device that can recognize the
VLAN tag, the VLAN tag is retained. If the data is to go to a device that
has no knowledge of VLANs (VLAN-unaware), the switch sends the
data without the VLAN tag.
Figure 1-2
IEEE 802.1Q VLAN Tag in Ethernet Frame
You must configure VLAN tagging on switch ports that interface to
end-stations that have tagged VLANs. If a switch or end-station port is
member of only a single, port-based VLAN, tagging is not required.
end-stations that have tagged VLANs. If a switch or end-station port is
member of only a single, port-based VLAN, tagging is not required.
To transmit tagged frames, you must configure a VLAN on the
end-station with a VLAN ID that matches the VLAN ID of a tagged
VLAN on the switch port and the VLAN ID of a VLAN at the remote
end-station. Refer to the next 3 chapters in this guide for complete
details on configuring VLANs on your HP-UX end stations.
end-station with a VLAN ID that matches the VLAN ID of a tagged
VLAN on the switch port and the VLAN ID of a VLAN at the remote
end-station. Refer to the next 3 chapters in this guide for complete
details on configuring VLANs on your HP-UX end stations.
Destination
Address
Source
Address
802.1Q
VLAN Tag
Type/Len
Data
Frame
Check
4 Bytes
User
Priority
Priority
3 bits
Canonical
1 bit
VLAN ID
12 bits
Format
Indicator
Indicator
2 Bytes
Tag
ID
Protocol
2 Bytes (Tag Control Information)