3Com 4007, Implementation Manual, Page: 290 / 684

290 C
HAPTER
14: V
IRTUAL
LAN
S
(VLAN
S
)
■
In allOpen mode, you need not supply the IEEE 802.1Q tagging.
However, to ensure line-speed throughput for overlapped
network-based IP VLANs in allOpen mode, supply the IEEE 802.1Q
tagging.
Example:
Network-based
VLANs
Figure 21 shows two IP network-based VLANs and two IPX
protocol-based VLANs. (The switch fabric module resides in slot 8 but is
logically represented above the other modules.)
In this configuration:
■
There are two Multilayer Switching Modules and the switch fabric
module. One module can handle servers; the other module can
handle clients.
■
There are four user-configured VLANs and the default VLAN:
■
VLAN1, the default VLAN on all modules, is untagged. The default
VLAN is not represented in the figure.
■
VLAN2, a network-based VLAN for IP with Layer 3 address 22.2.2.0
on the Multilayer Switching Module in slot 3. The IP routing
interface for IP VLAN 2 (22.2.2.10) on the Multilayer Switching
Module in slot 3 is on the same subnet as the IP routing interface
that is defined for VLAN2 on the Multilayer Switching Module in
slot 5 (22.2.2.20).
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VLAN3, a protocol-based VLAN for IPX-802.3 on the Multilayer
Switching Module in slot 3. The IPX routing interface is defined to
be on the same IPX network (1) as the IPX routing interface that is
defined for VLAN3 on the Multilayer Switching Module in slot 5.
Although there are overlapping ports in VLAN2 and VLAN3, the
protocol type is the distinguishing factor.
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VLAN4, a network-based VLAN for IP with Layer 3 address 44.4.4.0
on the Multilayer Switching Module in slot 5. The IP routing
interface for IP VLAN 4 is 44.4.4.10.
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VLAN5, a protocol-based VLAN for IPX-802.3 on the Multilayer
Switching Module in slot 5. The IPX routing interface is defined to
be on another IPX network (2).