Alcatel-Lucent 7750 SR OS, Руководство по настройке интерфейса

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Interface Configuration
7750 SR OS Interface Configuration Guide Page 83
DSLAM Dual Homing in Layer 2 TPSDA Model
Figure 20: DSLAM Dual-Homing Using MC-LAG
Figure 20 illustrates a network configuration where DSLAM is dual homed to pair of redundant
PEs by using MC-LAG. Inside the aggregation network redundant-pair of PEs is connecting to
VPLS service which provides reliable connection to single or pair of Broadband Service Routers
(BSRs).
MC-LAG and pseudo-wire connectivity, PE-A and PE-B implement enhanced subscriber
management features based on DHCP-snooping and creating dynamic states for every subscriber-
host. As in any point of time there is only one PE active, it is necessary to provide the mechanism
for synchronizing subscriber-host state-information between active PE (where the state is learned)
and stand-by PE. In addition, VPLS core must be aware of active PE in order to forward all
subscriber traffic to a PE with an active LAG link. The mechanism for this synchronization is
outside of the scope of this document.
VPLS
OSSG110
PE-A
PE-B
DSLAM
HGW
HGW
BSR
Synchronise
DHCP-state
IGMP-snooping
Arp-reply-agent
response