Table of Contents

BPX Switch Common Core Components

BPX Switch Common Core Components

This chapter describes theBPX Switch's common core hardware components:

• Broadband Controller Card (BCCs)
  
  
• 19.2 Gbps Operation with the BCC-4V
  
  
• Alarm/Status Monitor Card
  
  
• BPX Switch StrataBus 9.6 and 19.2 Gbps Backplanes
  
  

The BPX switch Common Core group includes the components shown in Figure 3-1:

• Broadband Controller Cards:
  
  • BCC-4 backcard
    
    
  • or BCC-32 and associated BCC15-BC backcard
    
    

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    Note   The BCC-4 is required for VSI and MPLS features operation

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• Alarm/Status Monitor (ASM), a Line Module for the ASM card (LM-ASM).
  
  
• StrataBus backplane.
  
  

The BCC-4V provides a 16 x 32 crosspoint switch architecture to extend the BPX peak switching capability from 9.6 up to 19.2 Gbps peak. The BCC-4V also provides 4 MBytes of BRAM and 128 MBytes of DRAM.

The functions of the common core components include:

• ATM cell switching.
  
• Internal node communication.
  
  
• Remote node communication.
  
  
• Node synchronization.
  
  
• Network management communications (Ethernet), local management (RS-232).
  
  
• Alarm and status monitoring functions.
  
  

Broadband Controller Card (BCCs)

The Broadband Controller Card is a microprocessor-based system controller and is used to control the overall operation of the BPX switch. The controller card is a front card that is usually equipped as a redundant pair.

Slots number 7 and number 8 are reserved for the primary and secondary (standby) broadband controller cards. Each broadband controller front card requires a corresponding back card.

• For non-redundant nodes, a single BCC is used in front slot number 7 with its appropriate backcard.
  
  
• For redundant nodes, a pair of BCCs of matching type, are used in front slot numbers 7 and 8.
  
  

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  Note   The three types of BCCs with their proper backcards may be operated together temporarily for maintenance purposes, for example, replacing a failed controller card. Throughout a network, individual BPX switches may have either a single BCC-4V controller card or a pair of the identical type of BCC.

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The term BCC is used in this manual to refer to the functional operation of the Broadband Controller Card. When a difference in operation does occur, the specific type of BCC is specified.

The BCC-4V provides a 16 x 32 cross-point architecture that increases the peak switching capacity of the BPX switch to 19.2 Gbps, with a sustained non-blocking throughput of 9.6 Gbps.

Features

The Broadband Controller Card performs these major system functions:

• Runs the system software for controlling, configuring, diagnosing, and monitoring the BPX switch.
  
  
• Contains the crosspoint switch matrix operating at 800 Mbps per serial link or up to 1600 Mbps (BCC-4V).
  
• Contains the arbiter which controls the polling each high-speed data port and grants the access to the switch matrix for each port with data to transfer.
  
• Generates Stratum 3 system clocking and can synchronize it to either a selected trunk or an external clock input.
  
• Communicates configuration and control information to all other cards in the same node over the backplane communication bus.
  
  
• Communicates with all other nodes in the network.
  
  
• Provides a communications processor for an Ethernet LAN port plus two low-speed data ports. The BCC15-BC provides the physical interface for the BCC-32.
  The BCC-3-BC provides the physical interface for the BCC-3-32M, BCC-3-64M, and BCC-4V.
  

Each Broadband Controller Card includes the following:

• 68EC040 processor operating at 33 MHz.
  
  
• 32 Mb or 64 MB option for BCC-4.
  
  
• 4 Mb of Flash EEPROM for downloading system software.
  
  
• 512 Kbytes of BRAM for storing configuration data.
  
  
• EPROM for firmware routines.
  
  
• 68302 Utility processor.
  
  
• SAR engine processor operating at 33 MHz.
  
  
• Communication bus interface.
  
  
• HDLC processor for the LAN connection interface.
  
  
• Two RS-232 serial port interfaces.
  
  

Functional Description

The BPX switch is a space switch. It employs a crosspoint switch for individual data lines to and from each port. The switching fabric in each BPX switch consists of three elements for the BCCs (see Figure 3-2):

• Central Arbiter on each BCC.
  
  
• Crosspoint Switch.
  
  
  • 16 X 32 Crosspoint Switching Matrix on each BCC (2 X [12 X 12]) used for BCC-4V.
    
    
• Serial Interface and LAN Interface Modules on each BCC and on each Function Module.
  
  

The arbiter polls each card to see if it has data to transmit. It then configures the crosspoint switching matrix to make the connection between the two cards. Each connection is unidirectional and has a capacity of 800 Mbps (616.7 Mbps for cell traffic plus the frame overhead).

Only one connection at a time is allowed to an individual card.

Each card contains a Switch Interface Module (SIM) which merely provides a standardized interface between the card and the data lines and polling buses. The SIM responds to queries from the BCC indicating whether it has data ready to transmit.

With the BPX switch equipped with two BCCs, the cell switching is completely redundant in that there are always two arbiters, two crosspoint switches, two completely independent data buses, and two independent polling buses.

The BCC incorporates non-volatile flash EEPROM which permits new software releases to be downloaded over the network and battery-backup RAM (BRAM) for storing user system configuration data. These memory features maintain system software and configuration data even during power failures, eliminating the need to download software or reconfigure after the power returns.

The BPX switch cell switching is not synchronized to any external clocks; it runs at its own rate. No switch fabric clocks are used to derive synchronization nor are these signals synchronized to any external sources.

Node clocking is generated by the BCC. Because the BPX switch resides as an element in a telecommunications network, it is capable of synchronizing to higher-stratum clocking devices in the network and providing synchronization to lower stratum devices. The BCC can be synchronized to any one of three different sources under software control:

• An internal, high-stability oscillator.
  
  
• Derived clock from a BNI module.
  
  
• An external clock source connected directly to the BPX.
  
  

The BCC clock circuits provide clocking signals to every other card slot. If a function card needs to synchronize its physical interface to the BPX switch clock, it can use this timing signal to derive the proper reference frequency. These reference frequencies include DS1, E1, DS3, and E3.

Front Panel Description

The BCC front panel has four Led, three card status LEDs, and a LAN LED. (See Figure 3-3 and Table 3-1.)

The BCC runs self-tests continuously on internal functions in the background and if a failure is detected, the fail LED is lighted. If the BCC is configured as a redundant pair, the off-line BCC is indicated by the lighted stby LED. The stby LED also flashes when a software download or standby update is in progress. The LAN LED indicates activity on the Ethernet port.

19.2 Gbps Operation with the BCC-4V

To operate the BPX switch at up to a 19.2 Gbps peak throughput, these components are required:

• A 19.2 Gbps backplane
  
  
• BCC-4V or later controller cards
  
  
• One or more BXM cards
  
  
• Release 8.4.00 or later switch software
  
  
• A backplane NOVRAM that is programmed to identify the backplane as a 19.2 Gbps backplane.
  
  

Switch software does not allow node operation at 19.2 Gpbs unless it can read the backplane NOVRAM to verify that the backplane is a 19.2 Gbps backplane.

The 19.2 backplane can be visually identified by the small white card slot fan fuses at the bottom rear of the backplane. These fan fuses are approximately 1/4 inch high and 1/8 inch wide. The 9.6 Gbps backplane does not have these fuses.

If the BPX switch is a late model, then a 19.2 Gbps backplane is installed. You can be verify this by running the despond command which will display "Word #2 =0001" if the backplane NOVRAM has been programmed. If anything else is displayed, visually check the backplane for the fuses.

If the backplane is a 19.2 Gbps backplane, but the backplane NOVRAM has not been set to display Word #2 =0001, then you may use the cnfbpnv command to program the NOVRAM:

Are you sure this is a new backplane (y/n).
 

Step 2   Enter y

Step 3   Confirm that the change has been made by entering dspbpnv to confirm the response:

Word #2 =0001

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Note   If the change does not take place, it will be necessary to change the backplane NOVRAM. Contact Cisco Customer Service.

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Step 4   Enter switchcc to make switch software recognize the change.

If the backplane is not a 19.2 Gbps backplane, contact Customer Customer Service.

Back Cards for the BCC-4V

The backcards for the Broadband Controller Card serve as an interface between the BPX switch and the BPX switch network management system.

For the BCC-4V, the backcard is the BCC-3-BC. (These backcards are also known as the BCC backcards).

The BCC-4V provides important features such as support for up to 19.2 Mbps peak operation with BXM cards. Both BCCs in a node should be of the same type.

The backcard provides these interfaces:

• An 802.3 AIU (Ethernet) interface for connecting the node to a CWM NMS.
  
  
• A serial RS-232 Control Port for connecting to a VT100-compatible terminal or modem.
  
  
• A serial RS-232 Auxiliary Port for connecting to an external printer.
  
  
• External clock inputs at T1 or E1 rates, output at 8 kHz.
  
  

The face plate connectors are described in Table 3-2 and Table 3-3 and shown in Figure 3-4. The BCC15-BC is shown on the left and the BCC-3-BCC is shown on the right.

For specifications on cabling, refer to Chapter 32, BPX Switch Cabling Summary .

Another function of the line module back card is to provide two low-speed, serial communications ports, as described in Table 3-3:

CONTROL port
A bidirectional port for connecting the BPX switch to a local terminal or to a modem for a remote terminal dial-in connection.

AUXILIARY port
An output only port, typically used to connect to a printer dedicated to printing logs.

The Cisco WAN Manager NMS is connected to the LAN port on the BCC backcards. When control is provided via an Ethernet interface, you configure the node IP address by using the cnflan command for the BPX switch. For redundancy, also configure the LAN ports on both BCC back cards, each connected to an AUI adapter.

The LAN port of the primary Broadband Control Card is active. If the secondary Broadband Control Card becomes primary (active), then its LAN port becomes active. The Cisco WAN Manager workstation will automatically try to restore communications over the LAN and will interface with the newly active Broadband Controller Card.

For small networks, one Cisco WAN Manager workstation is adequate to collect statistics and provide network management. For larger networks additional Cisco WAN Manager workstations may be required. Refer to the Cisco WAN Manager Operations Guide.

Alarm/Status Monitor Card

The Alarm/Status Monitor (ASM) card is a front card. Only one is required per node and it is installed in slot 15 of the BPX switch. It is used in conjunction with an associated back card, the Line Module for the ASM (LM-ASM) card.

The ASM and LM-ASM cards are non-critical cards used for monitoring the operation of the node and not directly involved in system operation. Therefore, there is no provision or requirement for card redundancy.

Features

The ASM card provides a number of support functions for the BPX switch:

• Telco compatible alarm indicators, controls, and relay outputs.
  
  
• Node power monitoring (including provision for optional external power supplies).
  
• Monitoring of shelf cooling fans.
  
  
• Monitoring of shelf ambient temperature.
  
• Sensing for the presence of other cards that are installed in the BPX switch.
  
  

Functional Description

BPX switch system software commands the ASM card to activate the major and minor alarm indicators and relays.

There are four significant circuits controlled by the ASM processor:

• Alarm
  The alarm monitor controls the operation of the front panel alarm LEDs and ACO and history pushbuttons as well as the alarm relays that provide dry contact closures for alarm outputs to customer connections.
  
  
• Power supply monitor
  The power supply monitor circuit monitors the status of the -48V input to the shelf on each of the two power buses, A and B. The status of both the A bus and B power bus is displayed on the ASM front panel.
  
  
• Fan and temperature monitor
  Each of the three cooling fans is monitored by the fan monitor circuit which forwards a warning to the BPX switch system software if any fan falls below a preset RPM. Cabinet internal temperature is also monitored by the ASM which sends the temperature to the system software to be displayed on the NMS terminal. The range that can be displayed is 0 degrees to 60 degrees Centigrade.
  
• Card detection.
  
  

Front Panel Description

The front panel displays the status of the node and any major or minor alarms that might be present. Figure 3-5 illustrates the front panel of the ASM card. Each front panel feature is described in
Table 3-4.

Line Module for the Alarm/Status Monitor Card

The Line Module for the Alarm/Status Monitor Card (LM-ASM) is a back card to the ASM card. It provides a simple connector panel for interfacing to your alarm system. It is not required for system and ASM operation.

The LM-ASM backcard must be installed in back slot number 15.

Figure 3-6 illustrates the face plate of the LM-ASM which contains a single subminiature connector (see Table 3-5). The Alarm Relay connector provides dry-closure (no voltage) relay contact outputs.

BPX Switch StrataBus 9.6 and 19.2 Gbps Backplanes

The BPX switch may be equipped with a backplane that supports either a 9.6 or up to 19.2 Gbps operation. The 19.2 Gbps backplane can physically be identified by the card slot fuses on the bottom rear of the backplane. All BPX switch modules are interconnected by the BPX switch StrataBus backplane physically located between the front card slots and the back card slots.

Although the ATM data paths between the switching fabric and the interface modules are individual data connections, there are also a number of system bus paths for controlling the operation of the BPX switch. The StrataBus backplane, in addition to the 15 card connectors, contains these signal paths:

• ATM crosspoint wiring
  Individual paths to carry ATM trunk data between both the network interface and service interface modules and the crosspoint switching fabric.
  
  
• Polling bus
  To carry enable signals between the BCC and all network interface modules.
  
  
• Communications bus
  For internal communications between the BCC and all other cards in the node.
  
  
• Clock bus
  To carry timing signals between the BCC and all other system cards.
  
  
• Control bus
  Enables either the A-bus wiring or B-bus wiring.
  
  

All StrataBus wiring is completely duplicated and the two sets of bus wiring operate independently to provide complete redundancy. Either the A-side wiring or B-side wiring is enabled at any particular time by signals on the Control bus.