IBM PC Server 520 User Handbook Manual page 151

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10BaseT
10BaseT
Net 1
Net 5
HUB HUB
10BaseT
10BaseT
Net 6
Net 2
HUB
HUB
Router
Protocol
LAN Driver
LAN Driver
Port 1 Port 2 Port 3 Port 4
Port 1 Port 2 Port 4
Port 3
Adapter 1 Adapter 2
System Bus
Net 7
Net 3
10BaseT 10BaseT 10BaseT
10BaseT Net 4
Net 8
HUB HUB HUB HUB
.