Optical Service Channel Module
The optical service channel module (OSCM) provides a point-to-point, bidirectional communications link between DWDM nodes. This communications linkthe optical service channel (OSC)is similar in function to the data communications channel (DCC) used in Synchronous Optical Network (SONET) topologies. However, in addition to providing an out-of-band DWDM communications link, the OSCM interface card provides other functions in an MSTP network, such as clock synchronization and orderwire channel communications. The OC-3 formatted optical service channel is
Because the optical service channel is a point-to-point link, two OSCM interface cards are required for most configurationsone for the East-to-West span, and one for the West-to-East span. The OSCM interface card operates solely in Slots 8 or 10 on the ONS 15454 shelf assembly. It is important to note that the OSCM is used in amplified MSTP configurations only. For amplified MSTP systems, the optical service channel is split from the composite DWDM fiber signal at the booster amplifier before being distributed to the OSCM card. For unamplified (passive) DWDM configurations, the optical service channelcombiner/separator module (OSC-CSM) interface card (detailed in the
In addition to the OC-3 formatted optical service channel, the OSCM card provides a 100-Mbps
Figure 9-3 shows the faceplate layout of the OSCM.
Figure 9-3. OSCM Card Faceplate Diagram
OSC-CSM provides the equivalent functionality of the OSCM interface card. In contrast to the OSCM interface, the OSC-CSM provides
After the OSC is extracted from the composite DWDM fiber signal and distributed to the OSC interface, the remaining composite signal is distributed to optical add/drop multiplexer (OADM) units for customer channel access.
Unlike the OSCM, the OSC-CSM can be operationally inserted in any of the service interface slots of the ONS 15454 shelf assemblySlots 16 or 1217. Figure 9-4 shows the faceplate layout of the OSCM.
Figure 9-4. OSC-CSM Card Faceplate Diagram
Alarm Interface Controller Card
The Alarm Interface Controller (AIC-I) card used for ONS 15454 MSTP operation is the exact same AIC-I card used for ONS 15454 MSPP configurations. The features/functions of the AIC-I interface were covered in Chapter 6. The information is repeated here for convenience.
The AIC-I card is an optional circuit pack that is installed in shelf Slot 9. The faceplate of the card is marked with a red diamond, corresponding to the symbol
When is the AIC-I card required? The card provides four main capabilities to the network operator:
Each of these major functions, along with the associated card faceplate LEDs and cabling connectors, is covered in the
Figure 9-5. AIC-I Card Faceplate Diagram
An earlier version of the Alarm Interface Controller is called the AIC (no- I ). This older version provides a more limited environmental alarm-monitoring capacity and does not provide user data channel access or input voltage monitoring. Although they may be installed in some existing systems, Cisco no longer produces the AIC version.
Similarly to all ONS 15454 common control cards, the AIC-I has a FAIL LED and ACT LED on the upper part of the card faceplate, just below the top latch. The FAIL LED is red and indicates that the card's processor is not ready for operation. This LED is normally illuminated during a card reset, and it flashes during the card boot-up process. If the FAIL LED continues to be illuminated, this is an indication that the card hardware has
Environmental alarms are associated with events that affect the operation of the system and are specific to the
Figure 9-6. Environmental Alarms Reported Using AIC-I Card Interfaces
CTC enables the user to provision several parameters
Figure 9-7. Backplane Environmental Alarm Connections
By using an additional piece of hardware, called the Alarm Expansion Panel (AEP), the AIC-I can actually be used to provide up to 32 alarm inputs and 16 outputs, for a total of 48 connections. The AEP is a connector panel that is wired to a subset of the environmental alarm wire-wrap pins and attached to the backplane. Cables can then be installed from the AEP to an external terminal strip for connecting alarm contacts to the system.
One interesting application that involves the use of both an environmental alarm and a control is referred to as a "virtual wire." A virtual wire enables the user to consider the activation of an incoming environmental alarm as triggering the activation of a control. One such scenario is shown in Figure 9-8, where the activation of an alarm at the remote location of Node A causes a control to activate an audible alarm at the staffed location of Node B. A virtual wire is used to associate the alarm with the control activation.
Figure 9-8. Virtual Wire Operation
Orderwires allow technicians to attach a phone to the faceplate of the AIC-I card and communicate with personnel at other ONS 15454 MSPP sites. The AIC-I provides two separate orderwires, known as local and express. These can be used
Phone sets are connected to the AIC-I using the two standard RJ-11
Phone sets are connected to the AIC-I using the two standard RJ-11 jacks marked LOW (Local Orderwire) and EOW (Express Orderwire). A green LED labeled RING is provided for each jack. The LED lights and a buzzer/ringer sounds when the orderwire channel detects an incoming call.
Power Supply Voltage Monitoring
User Data Channels
Four point-to-point data communications channels are provided for possible network operator use by the AIC-I, with two user data channels (UDC-A and UDC-B) and two data communications channels (DCC-A and DCC-B). These channels enable networking between MSPP locations over embedded overhead channels that are
The UDC-A and UDC-B channels use the F1 Section overhead byte to form a pair of 64-kbps data links, each of which can be routed to an individual optical interface for connection to another node site. The DCC-A and DCC-B use the D4-D12 line-overhead bytes to form a pair of 576-kbps data links, which are also individually routed to an optical interface.