GarrettCom 1016 Magnum 1000 Workgroup Hubs, Installation and User Guide 04/02, Packet Forwarded

Internal packets are forwarded when the destination is NOT IN the address table.

FWD-X LED “ON”

Figure 4.2a: Internal

Magnum 1000 Workgroup Hubs Installation and User Guide (04/02)

4.2Magnum 1000’s with BPM Local Bridge Functionality

When configured with a BPM, a Magnum 1000 Workgroup Hub and its

attached devices are bridge-isolated from the network segment connected through the BPM. The bridge functionality of the BPM bridge modules is described here.

1.Bridge Functions: Each BPM card contains a compact local bridge module which filters and forwards packets at full Ethernet wire speed. These micro-bridges are self learning and have small (256 user) address tables.

Packet filter/forward decisions are made based on whether the packet source is internal (originates within the local Magnum 1000) or external (originates from upstream

on the attached segment). If the packet’s source is internal, it is forwarded to the outside only if the destination address is not in the address table. Figure 4.2a shows

an internal packet being forwarded to the external segment.

Packet Forwarded

Figure 4.2b show the

cases where an internal packet is filtered. When the packet’s source is external, it is forwarded to the inside only if the destination address is in the address table.

Internal packets are filtered when the destination is IN the address table.

The filter/forward

handling of external packets

are shown in figures 4.2c and 4.2d respectively. When an internal packet’s source address is not already in the address table, it is written

Figure 4.2b: Internal Packet Filtered

External packets are forwarded when the destination is IN the address table.

FWD-I LED “ON”

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