3Com S7902E, Configuration Manual

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1-2
Figure 1-1 Scenario for one-to-one/multiple-to-one VLAN mapping
PC
VoD
VoIP
VLAN 1
VLAN 2
VLAN 3
PC
VoD
VoIP
VLAN 1
VLAN 2
VLAN 3
PC
VoD
VoIP
VLAN 1
VLAN 2
VLAN 3
PC
VoD
VoIP
VLAN 1
VLAN 2
VLAN 3
Home gateway
Home gateway
…
…
Home gateway
Home gateway
Campus switch
VLAN 1-> VLAN 101
VLAN 2-> VLAN 201
VLAN 3-> VLAN 301
VLAN 1-> VLAN 102
VLAN 2-> VLAN 202
VLAN 3-> VLAN 302
VLAN 101~200-> VLAN 501
VLAN 201~300-> VLAN 502
VLAN 301~400-> VLAN 503
VLAN 1-> VLAN 111
VLAN 2-> VLAN 211
VLAN 3-> VLAN 311
VLAN 1-> VLAN 112
VLAN 2-> VLAN 212
VLAN 3-> VLAN 312
Corridor switch
VLAN 111~210-> VLAN 501
VLAN 211~310-> VLAN 502
VLAN 311~410-> VLAN 503
Distribution
network
DHCP client
DHCP server
Corridor switch
…
…
…
…
To differentiate home users that are using the same service, you need to perform one-to-one VLAN
mapping to map the service traffic to different VLANs by user on the corridor switches. However, an
access device on the distribution layer is likely unable to support the number of VLANs required for this
type of VLAN mapping. To reduce the number of VLANs required on the edge device at the distribution
layer, you can adopt many-to-one VLAN mapping. This type of VLAN mapping maps the VLANs
carrying the same service of different users to the same VLAN while isolating the service traffic of
different users.
One-to-Two VLAN Mapping and Two-to-Two VLAN Mapping
One-to-two VLAN mapping and two-to-two VLAN mapping are mainly applied in networking
environments as shown in Figure 1-2 . In Figure 1-2 , two VPN A users located in different regions (Site 1
and Site 2) communicate with each other across two service provider (SP) networks, that is, SP 1 and
SP 2.