Chapter 2 Network configuration 59
In Figure 15, 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 15 802.1Q tag assignment
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Tagged packet |
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CRC | Data | Tag | SA | DA |
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Port 1 |
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Port 6 |
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| Port 8 |
Port 5
Tagged member of VLAN 2
Untagged member of VLAN 2
BS45013A
As shown in Figure 16, 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 16 802.1Q tagging (after 802.1Q tag assignment)
PVID = 2
Port 4
Port 1 |
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| Port 3 |
| 802.1Q Switch | |||
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Port 6 |
| Port 7 |
| Port 8 |
Port 5
Tagged member of VLAN 2
CRC Data Tag SA DA
Untagged member | CRC* (*Recalculated) | ||
of VLAN 2 |
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Data | |||
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| Priority |
| CFI |
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SA | Outgoing | |
untagged packet | ||
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DA | ||
(tag removed) |
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Key |
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Priority | - User_priority |
CFI | - Canonical format indicator |
VID | - VLAN identifier |
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BS45014A
