Black Box LH8000A-C, Инструкция по установке и эксплуатации

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Black Box Dual-Speed Stackable Hubs Installation and User Guide
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Packet
Source Destination Address Table Filter/Forward
Source Address Address Maintenance Action
10 Mb Not in table Not in table Add source to table Forward
10 Mb Not in table In table Add source to table Filter
10 Mb In table Not in table None Forward
10 Mb In table In table None Filter
100 Mb Not in table Not in table Add source to table Forward
100 Mb Not in table In table Add source to table Filter
100 Mb In table Not in table None Forward
100 Mb In table In table None Filter
Table 4.1: LH8000A-M Dual-Speed Hub Functionality
2. Address Learning (Address Table Maintenance)
The LH8000A-M bridge module is a state machine design which has a total address
table capacity of 8K addresses. With a large address table, LH8000As can serve the needs of a
medium-sized to large network. Table 4.1 shows what filter / forward action the LH8000A-M
will take in each packet-processing situation, and when a new node address will be added to
the internal Address Table. When a new node-address packet comes into a port for the first
time, then the new source address is “learned” at the same time that the packet is forwarded.
After learning, subsequent packets from the same node address are routinely processed. The
address tables are flushed periodically to update the network status and to purge any inactive
stations from the tables of both domains.
3. Throughput Increase
By selectively forwarding packets from each domain to the other domain based on
its switching (bridging) logic, the LH8000A-M increases the available bandwidth for the users
on both sides of the network. As shown in Figure 4.1, it keeps the local traffic on each side
contained, preventing unnecessary packets and bad packets from traveling to the other domain
and using up bandwidth needlessly over there. This results in more available network
bandwidth on both sides and a throughput increase on for all users on both domains.
4. Software Transparency
The LH8000A-C and -M Dual-Speed Hubs need no software set-up and are
transparent to system and application software, including network management software.