5 Cables Nortel Secure Router 8012
Hardware Description
5-30 Nortel Networks Inc. Issue 5.3 (6 April 2009)
5.10 HSSI cable

5.10.1 Introduction

High Speed Serial Interface cable has two types: the DTE-to-DCE cable (HSSI interface cable)
and the DTE-to-DTE cable (null modem cable). All are 3 m in length.

DTE-to-DCE cable

DTE-to-DCE cable is the straight-through cable. The line sequences of the twisted pairs in the
(DB-50) SCSI-II connectors at the two ends are the same. They are used for the connection
between the HSSI interface and the communication device in the middle.

DTE-to-DTE cable

DTE-to-DTE cable is the crossover cable. The line sequences of the twisted pairs in the
(DB-50) SCSI-II connectors at the two ends are different. They are used for back-to-back
connection among the DTE devices.

5.10.2 Structure

DTE-to-DCE cable and DTE-to-DTE cable are both shielded twisted-pair cables. They use
the (DB-50) SCSI-II and have similar pin assignment as shown in Figure 5-18.
Figure 5-18 DTE-to-DCE cable
A
A
B
B
Label
W1
X0 X1
Table 5-16 shows the pin assignment of DTE-to-DCE cables (HSSI interface cable). Table
5-17 shows the pin assignment of DTE-to-DTE cables (null modem cable).
Table 5-16 Pin assignment of the DTE-to-DCE cable (HSSI interface cable)
Relation Color (DB50)
SCSI-II
Signal Direction (DB50)S
CSI-II
Signal
White 1 SG 1 SG Pair 1
Blue 26 SG
26 SG
White 2 RT+ 2 RT+ Pair 2
Orange 27 RT-
Å
27 RT-