GarrettCom DS50 - Manual (Page 30)

Magnum DS50 / DS60s Dual Speed Hubs Installation and User Guide (06/02)
4.0 OPERATION
This chapter describes the function and operation of the Magnum DS50 / DS60.
4.1 Dual-Speed Functionality
The repeater ports (port #1-5) of a Magnum DS50 / DS60 handles the two different
traffic domains separately. The DS50 / DS60 provides switched (bridged) connectivity between
the Ethernet (10Mbps) and Fast Ethernet (100Mbps) domains. It joins the two network
domains for unified operation and filters/ forwards packets in both directions to maximize
bandwidth utilization and performance. The Magnum DS50 / DS60 is a hardware plug-and-
play device. There is no software set-up to be done at installation or for maintenance. The
functions of the DS50 / DS60 is described in this manual.
Each time a packet is received on one domain of the bridge logic, the decision is
taken to either filter or forward the packet. Error packets are always filtered. For good packets,
the filter and forward decisions are made based on the destination addresses contained in each
packet. If the destination address is on the same domain from which the packet originated, then
it is filtered and not forwarded to the other domain. If the destination address is not found to be
a match in the address table for the originating domain, then it is forwarded to the other
domain. If it is a new node address coming in which the switch did not previously know about,
it “learns” the new address and puts it in the correct port address table. See “Address Learning”
for more details.
This diagram below shows the filter / forward logic for both domains at port # 1-5.
Magnum DS50 / DS60
Figure 4.1 : Filtering and Forwarding at port (1-5) in DS50 / DS60 Dual-speed Hubs
10 Mbps Domain
100 Mbps Traffic
10Mb Domain : 10Mbps packets are
forwarded when the destination addresse is
NOT in the 10Mb domain address table.
100Mbps Domain : 100Mbps packets are
forwarded when the destination address is
NOT in the 100Mb domain address table.
10Mbps Domain : 10Mbps packets are
filtered when the destination address is
in the 10Mbps domain address table.
100Mbps Domain : 100Mbps packets are
filtered when the destination address is
in the 100Mbps domain address table.
10 Mbps Traffic
100 Mbps Domain
Bridge I.C.
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