Black Box LR1102A-T1/E1 - Manual (Page 131)

26
V
IRTUAL
LAN F
ORWARDING
26.1 Managing VLAN Traffic
Figure 43 VLAN Forwarding: Multi-Tenant Internet Access
The example above shows each multi-tenant customer represented as a separate VLAN on the Ethernet switch. The
connection in the customer office can be routed or bridged, depending on whether the provider will be hosting customer
applications at the POP. The Ethernet switch passes a VLAN trunk to the Black Box LR1114A that forwards traffic,
based on the VLAN tags, from this interface to the multilink bundle.
At the POP, tagged traffic is forwarded to a VLAN trunk port on the Ethernet switch. Routing between customer
VLANs is provided by the POP router using sub-interfaces on the Gigabit Ethernet VLAN trunk. The customer LAN
subnet is extended all the way to the POP router making remote management of LAN services (e.g., DHCP, file servers.
SMTP) possible.
The VLAN forwarding feature has the added benefit of being able to support non-IP traffic since all traffic is forwarded
based only on the Layer 2 VLAN tag. Although Black Box products do not communicate using non-IP Layer 3
protocols, Black Box systems can forward these protocols.
The management VLAN feature provides in-band communication with the Black Box systems as well as the Ethernet
switches while remaining separate from customer traffic. The Black Box systems will examine the destination IP
address of any packets received on the management VLAN. If the destination is the Black Box, the address of the
Ethernet
Switch
Tagged VLAN
Trunk
Tasman 1400
Untagged Customer LANs
Multi-Tenant Building
Telco
Internet
Channelized T3
Tasman 6300
Ethernet
Switch
Gigabit
Ethernet
POP Router
LR1104A
LR1114A