Инструкции По Установке для 3com S7906E

 

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When configuring BPDU tunneling, go to these sections for information you are interested in: 

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Introduction to BPDU Tunneling 

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Introduction to BPDU Tunneling 

As a Layer 2 tunneling technology, BPDU tunneling enables Layer 2 protocol packets from 

geographically dispersed customer networks to be transparently transmitted over specific channels 

across a service provider network.  

Customers usually use dedicated lines in a service provider network to build their own Layer 2 networks. 

As a result, very often, a customer network is broken down into parts located at different sides of the 

service provider network. As shown in 

, User A has two devices: CE 1 and CE 2, both of 

which belong to VLAN 100. User A’s network is divided into network 1 and network 2, which are 

connected by the service provider network. When Layer 2 protocol packets cannot be transparently 

transmitted in the service provider network, User A’s network cannot implement independent Layer 2 

protocol calculation (for example, STP spanning tree calculation). In this case, the Layer 2 protocol 

calculation in User A’s network is mixed with that in the service provider network. 

Figure 1-1 BPDU tunneling application scenario 

ISP network

User A network 1

VLAN 100

User A network 2

VLAN 100

CE 1

CE 2

PE 1

PE 2

 

 

With BPDU tunneling, Layer 2 protocol packets from customer networks can be transparently 

transmitted in the service provider network: 

2)  After receiving a Layer 2 protocol packet from User A network 1, PE 1 in the service provider 

network encapsulates the packet, replaces its destination MAC address with a specific multicast 

MAC address, and then forwards the packet in the service provider network;