Transparent Lan Service (Tls); Tls Network Example - ZyXEL Communications MSC1000G User Manual

MSC1000G User's Guide
Table 47 Supported VDSL Profiles (continued)
PROFILE
Tone Spacing
(kHz)
Line Power
(dBm)

Transparent LAN Service (TLS)

10.8.3
Transparent LAN Service (also known as VLAN stacking or Q-in-Q) allows a service provider
to distinguish multiple customers VLANs, even those with the same (customer-assigned)
VLAN ID, within its network.
Use TLS to add an outer VLAN tag to the inner IEEE 802.1Q tagged frames that enter the
network. By tagging the tagged frames ("double-tagged" frames), the service provider can
manage up to 4,094 VLAN groups with each group containing up to 4,094 customer VLANs.
This allows a service provider to provide different services, based on specific VLANs, for
many different customers.
A service provider's customers may require a range of VLANs to handle multiple
applications. A service provider's customers can assign their own inner VLAN tags to traffic.
The service provider can assign an outer VLAN tag for each customer. Therefore, there is no
VLAN tag overlap among customers, so traffic from different customers is kept separate.
Before the switch sends the frames from the customers, the VLAN ID is added to the frames.
When packets intended for specific customers are received on the MSC, the outer VLAN tag is
removed before the traffic is sent.

10.8.4 TLS Network Example

In the following example figure, both A and B are Service Provider's Network (SPN)
customers with VPN tunnels between their head offices and branch offices respectively. Both
have an identical VLAN tag for their VLAN group. The service provider can separate these
two VLANs within its network by adding tag 37 to distinguish customer A and tag 48 to
distinguish customer B at edge device 1 and then stripping those tags at edge device 2 as the
data frames leave the network.
140
8A 8B 8C
4.3125 4.3125 4.3125
+17.5 +20.5 +11.4
8D 12A
4.3125 4.3125
+14.5 +14.5
Chapter 10 DSL Port Setup Screens