PLANET XGS3-24042 - Manual (Page 135)

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transmitted in VLAN3 when traveling in the ISP internet network while carrying two VLAN tags (the inner tag is
added when entering PE1, and the outer is SPVID), whereas the VLAN information of the user network is
open to the provider network. When the packet reaches PE2 and before being forwarded to CE2 from the
client port on PE2, the outer VLAN tag is removed, then the packet CE2 receives is absolutely identical to the
one sent by CE1. For the user, the role the operator network plays between PE1 and PE2, is to provide a
reliable layer-2 link.
The technology of Dot1q-tuunel provides the ISP internet the ability of supporting many client VLANs by only
one VLAN of theirselves. Both the ISP internet and the clients can configure their own VLAN independently.
It is obvious that, the dot1q-tunnel function has got following characteristics:
 Applicable through simple static configuration, no complex configuration or maintenance to be needed.
 Operators will only have to assign one SPVID for each user, which increases the number of concurrent
supportable users; while the users has got the ultimate freedom in selecting and managing the VLAN
IDs (select within 1~4096 at users’ will).
 The user network is considerably independent. When the ISP internet is upgrading their network, the
user networks do not have to change their original configuration.
Detailed description on the application and configuration of dot1q-tunnel will be provided in this section.
15.3.2 Dot1q-tunnel Configuration
Configuration Task Sequence of Dot1q-Tunnel:
1. Configure the dot1q-tunnel function on port
2. Configure the protocol type (TPID) on port
1. Configure the dot1q-tunnel function on the ports
Command Explanation
Port mode
dot1q-tunnel enable
no dot1q-tunnel enable
Enter/exit the dot1q-tunnel mode on the
ports.
2. Configure the type of protocol (TPID) on the ports
Command Explanation
Port mode
dot1q-tunnel tpid
{0x8100|0x9100|0x9200|<1-65535>}
Configure the type of protocol on TRUNK
port.
15.3.3 Typical Applications of the Dot1q-tunnel
Scenario:
Edge switch PE1 and PE2 of the ISP internet forward the VLAN200~300 data between CE1 and CE2 of the
client network with VLAN3. The port1 of PE1 is connected to CE1, port10 is connected to public network, the
TPID of the connected equipment is 9100; port1 of PE2 is connected to CE2, port10 is connected to public