Magnum DS880 Dual-Speed Stackable Hubs Installation and User Guide (05/01)
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Example 3 :
For additional expansion, DS880s can be expanded by stacking DS880-A “add-on”
units. The additional stacked ports are all auto-sensing dual-speed, and can be used at either
10Mb or 100Mb on a per-port basis.
The stacking cables connect the DS880 units and carry the signals for both the 100Mb
and the 10Mb domains. In a stack, all 10Mb ports are together in a 10Mb traffic domain while
all 100Mb ports are similarly together on a separate 100Mb traffic domain. When one DS880-B
unit with a bridge inside is present in a stack, its bridge will support all of the ports in the stack
and enable network traffic to move between the two stacked domains.
A Magnum DS880 stack operates as one dual-speed repeater. A dual-speed repeater is
both a 10Mb hub and a 100Mb hub at the same time. This means that the 10Mb traffic domain
obeys all of the rules of 10Mb shared Ethernet networks (hop counts, cable types, cable
distances, etc.) and can be treated as one 10Mb repeater accordingly. Separately, the 100Mb
traffic domain obeys all of the rules of 100Mb Fast Ethernet shared networks (hop counts,
PDVs, cable types, cable distances, etc.) and can be treated as one 100Mb repeater. Both traffic
domains function within the same physical DS880 hub or stack of hubs.
Figure 2.7.3 :
Stackof Magnum
DS880’s operate as
one 10/100 dual-speed
repeater
When expanding an Ethernet or Fast Ethernet installation, the Magnum DS880 Hubs
are ideally suited for connecting servers and stations that have (or may have in the future ! )
mixed speeds. Each traffic domain or segment has its own local traffic with the Magnum
DS880-B performing bridge-isolation of one domain from the other, filtering and selectively
forwarding 10Mb and 100Mb packets between the two domains. This keeps the traffic between
the domains to a minimum and provides peak performance on both domains.
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Print Server
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Router
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GARRETT
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