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LTP-8X optical line terminal
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Fig. 19.1. "VLAN for Subscriber" Service Model Architecture
"VLAN for Service" Architecture
S-VLAN model has a separate VLAN for every service. Consider its operation on an example of an
abstract S-VLAN 100 service.
S-VLAN 100 is used between OLT and service routers that is global for all subscribers in terms of this
service. When a service request is generated upstream, records are added to the MAC table in OLT
according to S-VLAN and subscriber's MAC address. In case of downstream traffic, a corresponding
subscriber of the service is determined based on the MAC table.
If destination address of downstream transmission is not known (broadcast or unknown unicast), i. e.
the GEM port can not be determined, two options are possible:
— transmission through a dedicated broadcast GEM port (traffic is transmitted to all subscribers);
— transmission to every subscriber through a GEM port corresponding to the service.
The destination address, in case it is unknown (broadcast or unknown unicast), will be determined
based on the method implemented in a definite service model.
The architecture of this service model is shown in Fig. 19.2.
Fig. 19.2. "VLAN for Service" Service Model Architecture
