Transparent Bridging for Ethernet LANs

Transparent Bridge Figure 27 shows how the Forwarder and the Hardware Accelerator process a frame.

Forwarder Example

A frame arrives at the

Drop

TB Forwarder.

the frame.

YES

 

YES

 

 

 

 

 

 

 

 

 

 

Is

NO

Do

NO

Is

NO

 

the MAC

the inbound

Learn the Source

Source Address in the

 

filters

 

flag for a Unicast or

 

forwarding

 

match?

 

Multicast frame

 

Address.

table?

 

 

 

set?

 

 

YES

 

 

 

YES

 

 

Is

 

 

 

Is

 

 

the MAC

NO

TB Forwarder checks

 

the MAC

YES

 

 

Source Address on the

 

Destination Address in

 

if any filters are set.

 

 

 

the forwarding

 

 

Permanent Station

 

 

 

 

 

 

 

table?

 

 

 

Address

 

 

 

 

 

 

List?

 

 

YES

 

Do

NO

NO

 

 

 

 

 

 

 

 

 

filters

Drop

 

 

TB Forwarder checks

 

 

 

 

 

match?

 

 

 

 

 

the frame.

 

 

if any filters are set.

 

 

 

 

 

 

 

 

 

 

 

 

 

YES

 

 

 

 

Do

YES

Drop

TB Forwarder gives the

 

 

filters

 

 

 

 

 

match?

 

the frame.

frame to the handlers

 

 

 

 

 

 

that are in the

 

 

 

 

 

forwarding state.

 

 

NO

 

 

 

 

 

 

TB Forwarder gives the

 

 

 

 

 

 

frame to the appropriate

 

Handler sends

 

 

 

 

handler as found in the

 

the frame.

 

 

 

 

forwarding table.

 

 

 

 

 

 

Figure 27. How the Forwarder and Hardware Accelerator Process a

Frame

Forwarder

In addition, the Forwarder collects the following types of statistics:

Statistics

• Filtering

 

LAN link

WAN link

Link error

Bridging

49

T0008-16F

Release 5.2M

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Image 53
EXP Computer S200 manual Forwarder Example, Statistics, Filtering, LAN link WAN link Link error