User guide

EDA System Services
48 1/1551-HSC 901 35/3 Uen C 2005-12-02
IP DSLAM
Router/BRAS
Application
Server
Outer VLAN
Inner VLANs Inner VLANs
Figure 36 VLAN per End-user
In the example in Figure 36, each user is assigned a different inner VLAN.
The End-users are thus layer 2 separated, since the IP DSLAM
(terminating and acting upon the inner VLAN) will not allow direct layer 2
traffic between the two End-users. The Router or BRAS terminates both
VLAN tagging, but acting only on the outer VLAN, and therefore supplying
access to the application server for all the End-users.
Figure 37 on page 48 illustrates another example of using QinQ, this time
for Multiple Server Access through the same Service.
IP DSLAM
Router/BRAS
Application
Server
Outer VLAN
Inner VLANs
Inner VLANs
Application
Server
ADSL
PVCs
Figure 37 VLAN per Server
In the example in Figure 37, different PVCs of the same End-user are
assigned with two different services using the same outer VLAN, but
different inner VLAN. When the VLAN tagging is terminated by the Router
or BRAS, traffic from one inner VLAN will be forwarded to one application
server, while the traffic from the other inner VLAN will be forwarded to the
other application server.