Cabling A Dual-Attached Station - 3Com CoreBuilder 3500 Getting Started Manual

44 C 4: C
HAPTER ABLING
Figure 20 Cabling the SAS Connection
SAS port
MODEM TERMINAL
INS
C
100 BASE - FX
1X
L
3C54321
E
T
PWR
4X
L
INS
E
ERR
T
Network cable
For more information about single-attached stations,
see the CoreBuilder 3500 Implementation Guide.
ETHERNET
10BT
2X 3X
L L
E E
T
T
5X 6X
L L
E E
T T
Duplex
SC connector

Cabling a Dual-Attached Station

An FDDI module connected as a dual-attached station
(DAS) is connected to both the primary and secondary
rings of an FDDI network. Use DAS connections
where reliability is important and additional fault
tolerance is required. Each DAS connection consists of
an A port and a B port. In a typical DAS configuration:
The primary ring's light signal is received on Port A
and reenters the primary ring through Port B.
The secondary ring's light signal is received on
Port B and reenters the secondary ring through
Port A.
The six FDDI ports are labelled A1 through A3 and
B4 through B6, as shown in Figure 21.
Figure 21 FDDI Module Front Panel
FDDI MMF
A1
L
3C35410
E
T
B4
PWR
L
INS
E
ERR T
Table 10 shows the associated ports that comprise
each possible DAS connection.
Table 10 DAS Connection Port Assignments
DAS Connection Port A
1 A1
2 A2
3 A3
A2 A3
L L
E E
T T
B5 B6
L L
E E
T T
Port B
B4
B5
B6