Blade ICE G8000 - Manual (Page 54)

RackSwitch G8000 Application Guide
54 „ Chapter 3: VLANs BMD00041, November 2008
In Figure 3-4 , tagged incoming packets are assigned directly to VLAN 2 because of the tag
assignment in the packet. Port 5 is configured as a tagged member of VLAN 2, and port 7 is
configured as an untagged member of VLAN 2.
Figure 3-4 802.1Q tag assignment
As shown in Figure 3-5 , the tagged packet remains unchanged as it leaves the switch through
port 5, which is configured as a tagged member of VLAN 2. However, the tagged packet is
stripped (untagged) as it leaves the switch through port 7, which is configured as an untagged
member of VLAN 2.
Figure 3-5 802.1Q tagging (after 802.1Q tag assignment)
Port 6
DA SA Tag Data CRC
Tagged packet
BS45013A
Port 7 Port 8
Port 1
Port 4 Port 5
Port 2 Port 3
802.1Q Switch
PVID = 2
Untagged member
of VLAN 2
Tagged member
of VLAN 2
B efore
BS45014A
Port 6 Port 7 Port 8
Port 1
Port 4 Port 5
Port 2 Port 3
802.1Q Switch
Key
Priority
CFI
VID - User_priority
- Canonical format indicator
- VLAN identifier
PVID = 2 Tagged member
of VLAN 2
Untagged member
of VLAN 2
After
DA
SA
Data
CRC* (*Recalculated)
Outgoing
untagged packet
changed
(tag removed)
DA SA Data CRC Tag
VID = 2 Priority
16 bits 3 bits 1 bit 12 bits
8100 CFI