Optical Card Protection; Protection Switching; Xtc Cards (Xtc-28-3/Xtc-14); Xtc Card Description - Cisco ONS 15327 User Documentation

Chapter 13 Card Reference
Electrical protection in the ONS 15327 is bidirectional; after a failure, automatic protection switching
(APS) switches the traffic from the working card to the protect card, where the signal stays until it is
manually switched back. In the ONS 15327, the working XTC card is installed in Slot 6, the protect XTC
is installed in Slot 5. If any circuits fail on the working XTC, all functionality switches to the protect
XTC card (not just the failed circuit).

13.2.3 Optical Card Protection

The ONS 15327 currently supports 1+1 protection to create redundancy for optical cards. Working and
protection spans are defined by card slot pairs. The same optical cards in any two slots can be paired for
protection. 1+1 protection pairs a single working card with a single dedicated protect card. If the working
card fails, the protect card takes over.

13.2.4 Protection Switching

Unidirectional switching allows traffic on the transmit and receive fibers to switch independently. With
bidirectional switching, transmit and receive lines switch together.
With non-revertive 1+1 protection, APS switches a signal after a failure from the working card to the
protect card and the signal stays switched to the protect card until it is manually switched back. Revertive
switching automatically switches the signal back to the working card when the working card comes back
online. 1+1 protection is unidirectional and non-revertive by default; revertive switching is easily
provisioned using Cisco Transport Controller (CTC).
The ONS 15327 Release 3.3 supports unidirectional path switched ring (UPSR) and bidirectional line
switched ring (BLSR) configurations, providing additional methods of optical protection.

13.3 XTC Cards (XTC-28-3/XTC-14)

This section describes the features and functions of the XTC cards.

13.3.1 XTC Card Description

The XTC cards perform system initialization, provisioning, alarm reporting, maintenance, diagnostics,
IP address detection and resolution, SONET DCC termination, system fault detection, and cross-connect
maintenance and management for the ONS 15327. The XTC cards also provide the circuitry for the DS-1
and DS-3 interfaces and ensure that the system maintains Telcordia timing requirements.
An XTC card is required to operate the ONS 15327 and can be used in a redundant or non-redundant
configuration.
Figure 13-5
Note You can connect to either the active or standby XTC using the LAN or CRAFT port, but cannot connect
to both cards simultaneously. Connecting to both the active and standby XTC at the same time results in
a loss of connectivity.
June 2002
Figure 13-2 shows the XTC-28-3 faceplate,
diagrams the functionality.
XTC Cards (XTC-28-3/XTC-14)
Figure 13-3 shows the XTC-14 faceplate, and
Cisco ONS 15327 User Documentation, R3.3
13-3