Figure 21 Policy-Based Vlan Assignment; Figure 22 802.1Q Tagging (After Policy-Based Vlan Assignment) - Nortel business policy switch 2000 User Manual

Figure 21 Policy-based VLAN assignment

Policy VLAN = 3
PVID = 2
Untagged packet
CRC Data SA DA
Before
As shown in
switch through port 5, which is configured as a tagged member of VLAN 3. The
untagged packet remains unchanged as it leaves the switch through port 7, which
is configured as an untagged member of VLAN 3.

Figure 22 802.1Q tagging (after policy-based VLAN assignment)

Policy VLAN = 3
PVID = 2
Untagged member
of VLAN 3
untagged packet
Port 1
Port 6
Figure 22, the untagged packet is marked (tagged) as it leaves the
Port 1 Port 2 Port 3
802.1Q Switch
Port 6 Port 7 Port 8
CRC
Data
SA
Outgoing
DA
(unchanged)
Chapter 2 Network configuration 115
Port 2 Port 3
802.1Q Switch
Port 7 Port 8
Untagged member
of VLAN 3
Tagged member
of VLAN 3
CRC* Data
(*Recalculated)
Key
Priority
CFI
VID
Using the Business Policy Switch 2000 Version 2.0
Tagged member
of VLAN 3
BS45011B
Tag SA DA
8100 Priority CFI VID = 3
16 bits 3 bits 1 bits
After
- User_priority
- Canonical format indicator
- VLAN identifier
12 bits
BS45012B