Cisco SCE2020-4XGBE-SM - Non-VAS Data Flow

12-7
Cisco SCE 2000 and SCE 1000 Software Configuration Guide
OL-7827-12
Chapter 12 Value Added Services (VAS) Traffic Forwarding
How VAS Traffic Forwarding Works
• Each line represents a flow
– Thick line is a non-VAS flow
– Thin line is a VAS flow
– Black line indicates part of a flow that does not have VLAN tag
– Red line indicates part of a flow that has a VLAN tag
Figure 12-3 illustrates the data flow from the subscriber to the network. Data flow from the network to
the subscriber works in exactly the same way, but is received on the network port (N) and transmitted on
the subscriber port (S).
Figure 12-3 Data Flow in a VAS System
Non-VAS Data Flow
The flow steps for a non-VAS flow are:
• A subscriber packet is received at the SCE platform port 1 (S).
• The SCE platform classifies the flow as non-VAS flow.
• The packet is sent to the network on port 2 (N).
1-S
2-N
3-S
4-N
1-S
2-N
3-S
No VAS
4-N
SCE
VAS
157201
S
N
S
N
VAS (without VLAN)
VAS (with VLAN)