GarrettCom Mini-Concentrator Magnum 700X - Manual (Page 33)

Magnum 700X Mini-Concentrators Installation and User Guide (05/98)
GARRETT
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Should the table become full, the
BPM will clear all entries in the
table by reinitializing itself.
When an external
packet’s source address is in the
address table, it is purged. This
can occur if a node has physically
moved to a different location. Figure 4.2d: External Packet Filtered
A summary of the filtering, forwarding, and address table maintenance performed by
the BPMs is shown in Table 4.2.
Table 4.2: BPM Functionality
Packet Source Destination Address Table Filter/Forward
Source Address Address Maintenance Action
Internal Not in table Not in table Add source to table Forward
Internal Not in table In table Add source to table Filter
Internal In table Not in table Nothing Forward
Internal In table In table Nothing Filter
External Not in table Not in table Add source to table Filter
External Not in table In table Add source to table Forward
External In table Not in table Purge source from table Filter
External In table In table Purge source from table Forward
2. Throughput Increase: By using a BPM to isolate a user group segment having
significant local traffic, it is possible to increase overall network throughput. For
example, a segment containing a group of workstations and servers may have heavy
local traffic, but only a small amount of traffic that is directed outside the segment. A
BPM connecting this segment to the rest of the network, as shown in Figure 4.2e, will
keep the local segment traffic isolated from the rest of the network, thus increasing the
effective bandwidth on both the local segment and the rest of the network.
External packets
are filtered when
the destination is
NOT IN the
address table.