Intel 480T, Руководство пользователя

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C H A P T E R 5 Virtual LANs (VLANs)
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Figure 7 illustrates two VLANs spanning two switches. On System
1, ports 9 through 12 are part of VLAN
Accounting ; ports 13
through 16 are part of VLAN Engineering . On System 2, ports 1
through 4 are part of VLAN Accounting ; ports 5 through 8, 15, and
16 are part of VLAN Engineering .
Figure 7: Two port-based VLANs spanning two switches
VLAN Accounting spans System 1 and System 2 by way of a
connection between System 1, port 12 and System 2, port 1. VLAN
Engineering spans System 1 and System 2 by way of a connection
between System 1, port 13, and System 2, port 16.
Using this configuration, you can create multiple VLANs that span
multiple switches, in a daisy-chained fashion. Each switch must
have a dedicated port for each VLAN. Each dedicated port must be
connected to a port that is a member of its VLAN on the next switch.
Tagged VLANs
Tagging is a process that inserts a marker (called a tag ) into the
Ethernet frame. The tag contains the identification number of a
specific VLAN, called the
VLANid .
The use of 802.1Q tagged packets may lead to the appearance of
packets slightly bigger than the current IEEE 802.3/Ethernet
maximum of 1,518 bytes. This may affect packet error counters in
other devices, and may also lead to connectivity problems if non-
802.1Q bridges or routers are placed in the path.
480t_018
3 4 2 1 7 8 6 5
11 12 10 9
13 16 15 14
3 4 2 1 7 8 6 5
11 12 10 9
13 16 15 14
Accounting Engineering
System 1
System 2