User guide

EDA System Services
1/1551-HSC 901 35/3 Uen C 2005-12-02
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As Figure 32 illustrates, EDA Access network support both BRAS and
multiple edge access scenario. The basic service identifier is a PVC
(denoted as logical access channel in Figure 32). A virtual switch controls
the traffic for each PVC in the network. It is important here to remark that
the virtual switch is automatically configured when a service is assigned to
an End-user. The Service VLAN1 in Figure 32 illustrates an EDA Service
that contains two provider services that might have different QoS demands.
The Ethernet in the Access Domain is capable of treating different frames
with different QoS classification differently. The EDA Service allows for
different CoS (Class of Service) flows with different QoS through the same
PVC thus ensuring differential treatment of traffic through the DSL
connection even if only one PVC is used.
A Service VLAN can also be used to create layer-2 connections to other
End-users, either locally or across a transport network, creating a
Transparent LAN Service (TLS).
The traffic to the End-user is identified by the PVC that it came from or was
destined to. Since a Service VLAN is a property of the Service, there is a
one to one traffic mapping between PVC and VLAN. However, it is also
possible to add a parameter to the PVC as the Service identifier. It is
possible to use Ethertype information and to create a service where the
traffic from one PVC is mapped to two VLANs (and two gateways)
according to the Ethertype (PPP or IP). Figure 33 on page 43 illustrates this
scenario.
Internet
Application
Server
BRAS
Access Node
Traffic
Ethertype:
IP
Traffic
Ethertype:
PPP
Service VLAN 2
Service VLAN 1
PPP
IP
Figure 33 Traffic Mapping to Two VLANs