Introduction To Multi-Role Host - 3Com 8800 Configuration Manual

3Com Switch 8800 Configuration Guide
interface, routing table, and sends VPN routing information over MPLS network using
BGP/OSPF interaction.
If supporting OSPF multi-instance, one router can run multiple OSPF procedures,
which can be bound to different VPN instances. In practice, you can create one OSPF
instance for each service type. OSPF multi-instance can fully isolate different services
in transmission, which can solve security problems with low cost to meet the needs of
customers. Generally, OSPF multi-instance is run on PEs; The CE running OSPF
multi-instance in the LAN is called multi-VPN-instance CE. At present, isolation of LAN
services implements by VLAN function of the switch. OSPF Multi-VPN-Instance CE
provides schemes of services isolation implemented on routers.
VPN-RED VPN-RED
Site1 Site1
OSPF Area0 OSPF Area0
Area 0 Area 0
OSPF 100 VPN-RED OSPF 100 VPN-RED
OSPF 200 VPN-GREEN OSPF 200 VPN-GREEN
Area 1 Area 1
VPN - G R EEN VPN - G R EEN
Si t e1 Si t e1
O SPF Ar ea1 O SPF Ar ea1
Figure 37-6 OSPF multi-instance application in MPLS/BGP VPN PE
Figure 37-7 Multi-VPN-instance CE application in conventional LAN

37.1.6 Introduction to Multi-Role Host

The VPN attribute of the packets from a CE to its PE lies on the VPN bound with the
ingress interface. This, in fact determines that all the CEs forwarded by the PE through
the same ingress interface belong to the same VPN; but in actual network
environments, a CE may need to access multiple VPNs through one physical interface.
Though you can configure different logical interfaces to meet this need, this
VPN - G R EEN VPN - G R EEN
Si t e2 Si t e2
O SPF Ar ea2 O SPF Ar ea2
PE3 PE3
CE11 CE11
MPLS VPN Backbone MPLS VPN Backbone
PE1 PE1
CE12 CE12
ospf 100 ospf 100
vpn-engineering vpn-engineering
opsf 200 opsf 200
vpn-rd vpn-rd
ospf 300 ospf 300
PE PE
vpn-finances vpn-finances
Multi-VPN-Instance CE Multi-VPN-Instance CE
37-9
Chapter 37 BGP/MPLS VPN Configuration
CE31 CE31
Area 2 Area 2
OSPF 100 VPN-GREEN OSPF 100 VPN-GREEN
CE21 CE21 VPN - R ED VPN - R ED
Si t e2 Si t e2
O SPF Ar ea1 O SPF Ar ea1
Area 0 Area 0
OSPF 100 VPN-RED OSPF 100 VPN-RED
OSPF 200 VPN-GREEN OSPF 200 VPN-GREEN
Area 1 Area 1
PE2 PE2
CE22 CE22
ospf 100 ospf 100
vpn-engineering vpn-engineering
opsf 200 opsf 200
vpn-rd vpn-rd
ospf 300 ospf 300
vpn-finances vpn-finances