Table of Contents

Trunk Interface Cards

Trunk Operating Modes
Trunk Card Maintenance
Loopback Test

Common Alarms, Controls, and Indicators
Universal Switching Module Enhanced

Introduction to the UXM-E Trunk Mode

Determining the UXM-E's Mode of Operation
Example Networks with UXM-Es

UXM-E Trunk Features

UXM-E Interfaces
Maximum Number of UXM-Es
Y-Cabled UXM-E Redundancy
Switchover to a Redundant UXM-E
Card Mismatch
The UXM-E as a Clock Source

Cellbus Bandwidth Usage

Planning for Cellbus Bandwidth Allocation
Calculating Cellbus Bandwidth Changes
ATM Across a Public ATM Network
Routing over Cell Trunks Only

The UXM-E in Trunk Mode

Types of Supported Traffic
Types of Connections on a UXM-E Trunk
Inverse Multiplexing over ATM on IGX Trunks
Adding an IGX Feeder
Adding and Removing IMA Group Links
Supported Segment Connections on the IGX Feeder Node
Activation and Configuration of a UXM-E in Trunk Mode
Alarms for Physical Lines and Logical Trunks

SCR and PCR Policing at Less than 50 CPS on UXM-E
Trunk Statistics for Troubleshooting

Summary Statistics

UXM-E Interface Cards

OC-3/STM1 Back Cards
T3 Back Cards
E3 Back Cards
T1 Back Cards
E1 Back Cards

Network Trunk Module

Y-Cable Redundancy for the NTM
NTM Status

T1 Interface Card (BC-T1)

BC-T1 Faceplate Description

E1 Interface Back Card (BC-E1)
Subrate Interface Card (BC-SR)
Y1 Interface Back Card (BC-Y1)

Trunk Cards

This chapter describes the hardware and functionality of IGX trunk cards. The description of each card includes:

• Function
  
  
• System interconnect
  
  
• Faceplate indicators
  
  

Other publications that relate to IGX operation are:

• The Cisco IGX 8400 Series Installation and Configuration publication describes installation, troubleshooting, user commands, repair and replacement, and the rack-mount Cisco IGX 8420-to-IGX 8430 conversion.
  
  
• The Cisco WAN Switching Command Reference publication and the Cisco WAN Switching SuperUser Command Reference publication describe standard user commands and superuser commands.
  
  
• The Cisco WAN Manager Installation publication and the Cisco WAN Manager Operations publication both contain information on network management.
  
  

Trunk Interface Cards

This section describes the IGX trunks. The card groups are:

Table 4-1 lists the trunk front cards, and Table 4-2 lists the corresponding trunk interface back cards.

Trunk Operating Modes

IGX trunk cards operate in either simple gateway or cell forwarding mode. Simple gateway supports service interworking, which lets Frame Relay connections terminate at ATM endpoints. For a description of simple and complex gateways, service and network interworking, tiered networks, trunks, ATM protocols, and cell and header formats, refer to the Cisco Systems Overview.

Trunk Card Maintenance

Trunk cards require no maintenance except for replacement after a confirmed failure.

Loopback Test

A trunk loopback test runs when an ATM trunk detects an integrated alarm. The loopback test indicates if the line or the card is faulty. A loopback test "pass" means the line is faulty, so a line alarm is subsequently indicated. A loopback test "fail" means the card is faulty. If the card is faulty, a switch occurs to an available Y-cable equipped redundant card.

Common Alarms, Controls, and Indicators

Front cards and back cards have faceplates with indicator LEDs. Most cards have both a green Active LED and a red Fail LED at the bottom of the faceplate. For definitions of the port status LEDs on a back card, refer to the section that describes the back card. Table 4-3 describes the common card status indicators for LEDs.

Universal Switching Module Enhanced

This description of the universal switching module (UXM-E) covers the following topics:

• An introduction includes sections on the UXM-E mode of operation, trunk-mode features, interface card list, card redundancy, card mismatch, clock sourcing, cellbus bandwidth usage, configuration for public ATM network service, and configuration for cell trunk-only routes
  
  
• Supported traffic and connection types
  
  
• Inverse multiplexing over ATM (IMA)
  
  
• Activation and configuration of a UXM-E for trunk-mode operation
  
  
• Supported traffic and connection types
  
  
• Alarms for physical lines and logical (IMA) trunks
  
  
• Descriptions of the faceplates on the back cards
  
  

The universal switching module (UXM-E) can function in one of two modes. In trunk mode, the UXM-E supports trunks in the network. In port mode, it as either an ATM User-to-Network Interface (UNI) or a Network-to-Network interface (NNI). The back cards support multiple ports operating at OC3/STM1, T3, E3, T1, or E1 rates.

Introduction to the UXM-E Trunk Mode

The UXM-E can transport ATM cells to and from the cellbus at a maximum rate of 310 Mbps in either direction. The UXM-E can support up to 8000 total connections in trunk mode.

The UXM-E communicates only ATM cells to either the network or the CPE. On the cellbus, however, the UXM-E communicates either ATM cells or FastPackets according to the card type. With another UXM-E, it communicates only in ATM cells. With other cards, the UXM-E communicates in FastPackets. Through its gateway functionality, the UXM-E translates between FastPackets and ATM cells so it can transport voice, data, or Frame Relay traffic that other cards have put in FastPackets.

Determining the UXM-E's Mode of Operation

The UXM-E detects reports its mode of operation to switch software when you first activate either a trunk to the network or a line on the UNI or NNI. If you activate a trunk, the UXM-E goes into trunk mode. If you activate a line, the UXM-E goes into port mode. The CLI commands for these operations are uptrk and upln, respectively. (The UXM-E description in this chapter lists important information about the commands that apply to the UXM-E, but the order of their use appears in the Cisco IGX 8400 Series Installation guide. For a detailed description of each command and its parameters, see the Cisco WAN Switching Command Reference.)

Example Networks with UXM-Es

Networks with both trunk mode and port mode UXM-Es appear in Figure 4-1 and Figure 4-2, respectively. The nodes in Figure 4-1 use only UXM-Es for port interfaces and trunk interfaces. Figure 4-2 shows a variety of cards providing interfaces for different traffic types.

The network carrying only ATM traffic appears in Figure 4-1. Each UXM-E trunk card in Figure 4-1 connects to either another UXM-E trunk card or a BXM operating as a trunk. The ATM UNI ports are the UXM-E port cards (for connection A), the BXM operating in port mode (for connection B), the ASI (for connection C), and the BXM feeder trunk (for connection D). Connection D is a two-segment connection. One segment of connection D exists between the BNM and AUSM on the Cisco MGX 8220 shelf, and the other segment exists between the BXM and the UXM-E UNI port.

A network with ATM traffic and FastPacket-based traffic appears in Figure 4-2. Connections A and B are ATM connections that terminate on UXM-E UNI port cards and a BXM operating as a UNI port. Connection C is a Frame Relay connection between a UFM and an FRM. Connection D is a voice connection between a CVM and CDP. Connection E is a local connection (DAXCON) between a UFM and a UXM-E UNI port on the same node. For connections C-E, the gateway function of the UXM-E packs and unpacks the FastPackets into and out of the ATM cells.

UXM-E Trunk Features

The following list broadly identifies the features of a UXM-E trunk. After the bulleted list, the remaining sections of this introduction contain tables that list the features on particular topics, such as interworking. Actual descriptions of the features appear in the section "The UXM-E in Trunk Mode".

• The UXM-E uses all four lanes of the cellbus.
  
  
• In trunk mode, the UXM-E supports up to 8000 connections.
  
  

• The maximum throughput is 310 Mbps—two times the OC-3 (STM1) rate. This maximum applies whether the back card is a 2-port or 4-port back card. In practical application, this maximum rate means that most trunk applications with an OC-3 interface would use the 2-port back card.
  
  
• The UXM-E supports ATM-to-Frame Relay network and service interworking.
  
  
• For the ABR connection types, the UXM-E supports EFCI marking, Explicit Rate Stamping, and Virtual Source/Virtual Destination (VS/VD).
  
  
• The UXM-E supports Y-cable redundancy with hot standby for very fast switchover.
  
  
• The front card has 128K cell buffers.
  
  
• For statistics support, the UXM-E provides real-time statistics counters and interval statistics collection for ports, lines, trunks, and channels.
  
  
• The UXM-E can form a logical trunk by grouping more than one T1 or E1 port. The name of this (purchased) option is Inverse Multiplexing over ATM (IMA).
  
  
• The on-board diagnostics are loopback, self-test, and background.
  
  

UXM-E Interfaces

Table 4-4 is a list of the UXM-E back cards. Figure 4-3 shows the UXM-E front card. Table 4-5 defines all possible combinations for the states of the front card status LEDs (Fail, Active, and Standby).

Maximum Number of UXM-Es

Switch software limits the number of logical trunks and ports on an IGX switch. The maximum number of UNI or NNI ports in an IGX switch is 64. The maximum number of logical trunks is 32. To determine the number of each logical type in the switch, add the number of ports on multiport cards and single-port cards. These sums cannot exceed 64 ports and 32 trunks. For example, using exclusively 2-port OC3 trunks, you could install:

2 trunks per card x 16 OC3 UXM-Es = 32 trunks

Switch software monitors the number of logical ports and trunks, not the number of UXM-Es. Therefore, the software keeps you from activating an excessive number of lines or trunks on the node rather than flagging the presence of too many cards.

Y-Cabled UXM-E Redundancy

The UXM-E features hot standby as a part of its Y-cable redundancy capability. With hot standby, the redundant card receives the configuration information as soon as you finish specifying redundancy. The standby card also receives updates to its configuration as the active card configuration changes. Hot standby lets the backup card go into operation as soon as necessary rather than waiting for the NPM to download the configuration.

Y-cable redundancy requires that both cards are active and available before you set up redundancy. Use Cisco WAN Manager or the CLI commands uptrk, addtrk, then addyred. (See also descriptions of addyred, delyred, dspyred, and ptyred in the Cisco WAN Switching Command Reference publication.)

Switchover to a Redundant UXM-E

If the card fails, a switchover occurs to a Y-cabled, redundant UXM-E card set if available. If the switchover occurs, the primary UXM-E acquires failed status, and the Fail LED turns on.

Card Mismatch

The UXM-E supports two types of card mismatch notification. The notification common to all cards occurs when you connect an unsupported back card to the front card. The mismatch notification unique to the UXM-E occurs if you attach a supported back card but one that has a different interface or a smaller number of the correct line types than what the UXM-E previously reported to software.

The UXM-E as a Clock Source

A UXM-E line or trunk can be the clock source for the node. Use the dspclksrcs command to display available clock sources, dspcurclk to show the current clock source, and cnfclksrc to specify a new clock source. To clear clock alarms, use clrclkalm.

Cellbus Bandwidth Usage

The cellbus consists of four operational lanes plus one backup lane. (The backup lane becomes active if a lane fails.) The FastPacket-based cards can use only one lane and communicate only in FastPackets. If a FastPacket-based card controls the cellbus, no ATM cells can be on the cellbus.

When the UXM-E has control of the cellbus, it can pass any of the following:

• ATM cells on all lanes (for example, with a daxcon between UXM-Es or when one UXM-E communicates with another UXM-E in the same switch)
  
  
• FastPackets on lane 1 simultaneously with ATM cells on lanes 2 through 4
  
  
• FastPackets on lane 1
  
  

Switch software monitors and computes cellbus bandwidth requirements for each card in the
Cisco 8400 series switches. For the UXM-E alone, you can change its cellbus bandwidth allocation. (You cannot view or alter bandwidth allocation for other cards.) The unit of measure for the ATM cell and FastPacket bandwidth on the cellbus is the universal bandwidth unit (UBU).

You can raise, lower, or check a UXM-E's UBUs with cnfbusbw. The cnfbusbw privilege level is 0—superuser. To check a UXM-E's UBUs, use dspbusbw or cnfbusbw. Any user can use dspbusbw. Each command's display provides the information you need to determine if you must increase the UBUs on a particular UXM-E. The only value you can change is allocated bandwidth.

The card-based default and maximum cellbus bandwidth for each interface appears in Table 4-5. Note that FastPackets require substantially less cellbus bandwidth than ATM cells. The FastPacket requirements in the figure and table reflect the restriction of FastPackets to one lane and the maximum processing rate of the gateway on the UXM-E.

The values you can view with the cnfbusbw and dspbusbw commands are:

• Minimum Required Bandwidth, the necessary bandwidth that switch software has calculated for the existing connections on the local UXM-E. The display shows the requirements for FastPackets, ATM cells, and the equivalent in total UBUs.
  
  
• Average Used Bandwidth is the average bandwidth usage.
  
  
• Peak Used Bandwidth is the peak bandwidth usage.
  
  
• Maximum Port Bandwidth is the maximum bandwidth that the back card can support. The FastPackets per second field has a dash-mark because only cells pass through the port.
  
  
• Allocated Bandwidth is the current cellbus allocation for the card. The field shows the UBUs, the bandwidth when only ATM cells are on the bus, and cells plus Fastpackets. The reason for cells alone and cells plus Fastpackets is that cells can exist on the cellbus with or without FastPackets. The last field under Allocated Bandwidth shows the formula to which the allocated values must adhere. (A description of the formula follows the example screen.)
  
  

Planning for Cellbus Bandwidth Allocation

With the Network Modeling Tool™ (NMT), you can use the projected load for all UXM-Es in the network to estimate their cellbus requirements. During normal operation, you can use Cisco WAN Manager to obtain the trunk and port statistics then decide whether to use cnfbusbw to increase the UBU allocation. If you are using only the CLI, you would need to establish a virtual terminal (vt) session to each node then execute dspbusbw or cnfbusbw.

Calculating Cellbus Bandwidth Changes

To determine how many UBUs are necessary, use the values for average bandwidth used in the following formula:

In most circumstances, the fps and cps values from average bandwidth used are sufficient. The peak bandwidth used values are primarily informational.

The information in Table 4-5 provides the ranges for the interface type. Note that, if you do the math according to the formula, you see that the value in the cells-alone column of Table 4-5 equals the result of adding half the FastPacket value to the cell value in the cells plus FastPackets column.

When you use dspbusbw, a yes/no prompt asks if you want firmware to retrieve the usage values. If you enter a "y," the UXM-E reads—then clears—its registers and thus restarts statistics gathering. If you enter an "n," switch software displays the current values that reside in control card memory (on the NPM). The values in memory come from the last update from the UXM-E.

ATM Across a Public ATM Network

The UXM-E can support trunking across a public ATM network so both virtual channel connections (VCCs) and virtual path connections (VPCs) traverse a single virtual path trunk. This feature lets you map multiple trunks to a single port of an NNI. The NNI connects to either a public or private ATM network. The virtual trunk package is a lower-cost alternative to leased circuits but still has the full set of Cisco ATM traffic management capabilities. This application requires two UXM-Es and a clock from an external source. The rates can be OC-3/STM-1, T3/E3, or T1/E1.

UXM-Es Configured for a Public ATM Network

Refer to Figure 4-3 as you read the steps for the following example set-up:

Step 1   Connect a cable between each of the following:

• 8.1 and 9.1
  
  
• 8.2 and 9.2
  
  
• 8.3 and 9.3
  
  
• 9.4 and the public network
  
  

Step 2   Configure trunk 8.1, 8.2, and 8.3 to use VPC 101, 102, and 103, respectively.

Step 3   Add 3 VPC connections from 9.1, 9.2, and 9.3 to 9.4. At the far end, use the same VPCs.

Routing over Cell Trunks Only

You can specify trunk cell routing only as an option when you add a connection between UXM-E, ASI, or BXM ports. When you enable trunk cell routing, switch software routes across only the cell-based trunk cards BNI, BXM, and UXM-E: no conversion to FastPackets occurs on the route. If you disable trunk cell routing, the routing process can select a FastPacket-based trunk and so decrement the number of available gateway connections. Also, using a FastPacket-based trunk may result in increased network delays. Therefore, enabling trunk cell routing is the preferred choice when you add a connection at a BNI, BXM, or UXM-E.

If you add connections at other port cards, such as a UFM or ALM/A, switch software does not display the trunk cell routing option.

On the CLI, the addcon prompt for this option appears as "trunk cell routing restrict y/n?" It appears after you enter either the ATM class of service or after you finish specifying all the individual bandwidth parameters that apply to the current connection type. You can specify whether the default for trunk cell routing is "Yes" or "No" through the cnfnodeparm (superuser) command.

The UXM-E in Trunk Mode

The UXM-E trunk can communicate ATM cells that originated at an ATM endpoint or—through its on-board gateway functionality—FastPacket-based traffic such as voice, data, and Frame Relay. A UXM-E trunk can connect to the following trunk cards:

• UXM-E
  
  
• BXM
  
  

Types of Supported Traffic

As previously stated, the UXM-E trunk can connect to only another UXM-E trunk or a BXM trunk. On the other hand, the types of traffic that traverse a UXM-E trunk can originate at ATM ports or other types of ports. The types of traffic that a cell on a UXM-E trunk can carry appear in Table 4-7 . Table 4-7 shows the traffic types that ATM cells can carry where the payload originated as a FastPacket.

Types of Connections on a UXM-E Trunk

This section introduces the connections that a UXM-E trunk supports. The context of each description is the trunk rather than the connection endpoints. The purpose of these descriptions is not only to inform but also help you plan the network. Some definitions overlap because a connection may qualify as more than one type.

• A Cell connection carries information that exists in ATM cell format throughout the path. On a UXM-E trunk, therefore, the only cell connections are those that have originated on a UXM-E port at one end and remain in cell format throughout the connection.
  
  
• A Gateway connection carries information that normally exists in ATM cell format but is translated to FastPacket format for some purpose at some point along the path. Reason for the translation could be that the connection terminates on a FastPacket-based card, is a network connection, or includes a FastPacket-based trunk card in the route.
  
  
• A Networking connection carries network messages between nodes and terminate as FastPackets (and therefore are also gateway connections).
  
  
• A User-connection is a connection that a user has added at the current node. User-connections can be cell connections or gateway connections. User connections are mutually exclusive of via connections and network connections.
  
  
• A Via connection passes through a node and does not terminate on the node. You can neither view nor alter a via connection because the connection does not terminate on the node (the node that owns the connection has made the via node and trunk a part of the route).
  
  
• An Interworking connection is a service or network interworking connection in which one end terminates as ATM and the other as Frame Relay. Interworking connections are a subset of gateway connections.
  
  

Because network messages use gateway channels, they subtract from the total number of available gateway connections. For each active port, the UXM-E reserves 270 gateway connections for networking regardless of the interface type. Therefore, with a fully-utilized 8-E1 or 8-T1 back card, the UXM-E reserves up to 2160 connections. Because these numbers potentially represent a very significant reduction in the number of gateway connections for user-data, switch software lets you specify a maximum number of active ports on the back card. The most applicable interfaces for this capability are the T1 and E1 ports, especially with Inverse Multiplexing Over ATM (IMA). See the section "Inverse Multiplexing over ATM on IGX Trunks" for the description of IMA.

You can specify the maximum number of logical trunks that can be active on a card through Cisco WAN Manager or the CLI. The applicable CLI command is cnftrkport. For example, if you intend an eight-port card to have two logical (IMA) trunks, you can use cnftrkport to specify a maximum number of two trunks. Software would therefore reserve 540 connections for network messages rather than the 2160 connections if you did not specify a maximum.

Inverse Multiplexing over ATM on IGX Trunks

Inverse Multiplexing over ATM (IMA) lets you group physical T1 or E1 lines to form a logical trunk. A logical trunk consisting of more than one T1 or E1 line supports connections with data rates that are much higher than the T1 or E1 rate. System software lets you specify IMA so that one or more physical lines within the logical trunk can serve as backup if a line fails.

IMA characteristics are as follows:

• All physical ports of an IMA trunk use the same line configuration.
  
  
• The node maintains a set of retained links for the IMA trunk to keep it active. The IMA trunk does not fail unless the number of active trunks is less than the user-specified number of retained links.
  
  
• The IMA trunk can provide a clock source or clock path (see cnftrk command). The first (the lowest numbered) available physical line is used. If this line fails, the next available line within the IMA provides the clock source or clock path.
  
  
• Full support for individual physical line alarms and statistics.
  
  

Adding an IGX Feeder

The IMA feeder node feature provides redundancy in case one of the physical lines on an IMA trunk fails. This reduces the chance of a single point of failure when a single feeder trunk is out of service. In addition, this feature allows you to configure the services on a feeder node instead of a routing node.

Figure 4-5 shows an example of an IGX feeder topology.

Adding and Removing IMA Group Links

When you configure an IMA trunk through Cisco WAN Manager or the cnftrk command, you enter the number of retained links. This represents the number of ports that must remain active for the IMA trunk itself to remain active. If a physical line goes out of service, but the number of active lines is at least as great as the retained links value, the IMA trunk remains active even though the node goes into major alarm. Also, the available load bandwidth is adjusted according to physical line status, so the switch does not reroute connections after a line failure unless the used bandwidth becomes greater than the available bandwidth.

In Figure 4-6, the number of retained links is set to 3. If line 1 fails for example, trunk 8.1-4 will continue functioning, however, the node will show major alarm due to the physical line failure.

Figure 4-7 shows an example of IMA protocol overhead. In the example, DS0 1 is reserved for an IMA group with 1 to 4 physical lines and DS0 2 is reserved for an IMA group with 5 to 8 physical lines.

Supported Segment Connections on the IGX Feeder Node

Figure 4-8 shows an example of configuring a two-segment connection for IGX feeder node functionality.

Figure 4-8: Sample Two-Segment Connections

Table 4-8 lists the corresponding routing and feeder endpoints with applicable gateway and load types and also connection types.

Figure 4-9 shows an example of configuring a three-segment connection for IGX feeder node functionality.

Table 4-9 lists the corresponding feeder endpoints with applicable gateway and load types and connection types.

Activation and Configuration of a UXM-E in Trunk Mode

When you insert a new UXM-E into the backplane or apply power to the IGX node, UXM-E firmware reports the card type and number of physical lines on the back card. Switch software can then determine the allowed range and characteristics of trunks for you to configure. Software thus prevents you from exceeding the maximum number of trunks on the switch as you activate them through either Cisco WAN Manager or uptrk on the CLI.

Table 4-10 shows the trunk characteristics you can configure for each interface type through either Cisco WAN Manager or the cnftrk command on the CLI. Table 4-10 also shows the fixed parameters.

Alarms for Physical Lines and Logical Trunks

Variations exist in the way switch software supports alarms for physical lines and logical trunks for a trunk-mode UXM-E. The following list summarizes the approach to physical lines and trunks:

• A UXM-E trunk is mapped to a physical line object.
  
  
• A physical (non-IMA) trunk is mapped one-to-one with a physical line.
  
  
• An IMA trunk is mapped to more than one physical line.
  
  
• All line alarms (LOS, LOP, and so on) are reported as physical line alarms.
  
  
• Software reports other trunk alarms (such as communication failure, communication break, and so on) as trunk alarms in a manner similar to other, non-UXM-E trunk alarms.
  
  
• For non-IMA trunks, the alarm includes the physical line alarm.
  
  
• For IMA trunks, the trunk and physical line alarms are separate and distinct.
  
  

The physical layer trunk alarms include LOS, LOF, AIS, Yel, LOP, Path AIS, and Path Yel. To view these alarms, use the dspphysln command. When you execute dspphysln, any existing alarms appear as the physical line status. For a trunk with one physical line (such as an OC3 trunk or T1/E1 without IMA configured), the integrated alarm status is also shown by the dsptrks command.

You can enable the physical line statistical alarm on the CLI through the cnfphyslnalm command. You can display existing alarms through the dspphyslnerrs command and clear the alarms through the clrphyslnalm command.

SCR and PCR Policing at Less than 50 CPS on UXM-E

This section provides descriptions of lowered PCR minimum policing values supported by the BXM and UXM-E. When policing is off, connections can be set with PCR values as low as 6 cells per second (CPS). The minimum SCR value can be set to 6 CPS regardless of interfaces. Table 4-11 lists the minimum PCR values for different BXM and UXM-E cards when policing is enabled.

Figure 4-10 shows an application example enabled by the PCR minimum value feature. In the example, less than 19.2 kbps Frame and ATM connections are set up across two carrier Frame and ATM networks with the policing function enabled at the boundary of the two carrier networks. The PCR value of segment 2 is set to the new minimum PCR policing value supported by the NNI facing BXM. For the BXM cards where the minimum PCR values are lowered, over-provisioning of bandwidth for low speed connections (on segment 2) is reduced or eliminated.

Trunk Statistics for Troubleshooting

In Release 9.3, switch software separates the UXM-E trunk statistics into physical statistics and logical statistics. (This separation is a deviation from other schemes for trunk statistics management.) The commands in this section are useful primarily for troubleshooting.

The CLI commands cnfphyslnstats, dspphyslnstatscnf, and dspphyslnstathist apply to the statistics for physical lines within an IMA trunk. You can enable the physical line statistics by using cnfphyslnstats, display the configuration for statistics with dspphyslnstatcnf, and display the statistics themselves with dspphyslnstathist.

Summary Statistics

You can view summary statistics for a UXM-E trunk through Cisco WAN Manager or the CLI. The CLI commands are dspportstats and dsptrkstats.

UXM-E Interface Cards

This section provides basic information on the interface back cards for the UXM-E. The information consists of a general description, an illustration of the card faceplate, and a table describing the connectors and status LEDs. For details on the line technology of each type of interface, see the appendix "System Specifications."

The model numbers of the back cards and the order of their appearance are:

• BC-UAI-4-155-MMF
  
  
• BC-UAI-4-155-SMF
  
  
• BC-UAI-2-155-SMF
  
  
• BC-UAI-2-SMFXLR
  
  
• BC-UAI-4-SMFXLR
  
  
• BC-UAI-4-STM1E
  
  
• BC-UAI-6-T3
  
  
• BC-UAI-3-T3
  
  
• BC-UAI-8-T1-DB-15
  
  
• BC-UAI-4-T1-DB-15
  
  
• BC-UAI-6-E3
  
  
• BC-UAI-3-E3
  
  
• BC-UAI-8-E1-DB-15
  
  
• BC-UAI-8-E1-BNC
  
  
• BC-UAI-4-E1-DB-15
  
  
• BC-UAI-4-E1-BNC
  
  

OC-3/STM1 Back Cards

The OC3/STM1 back cards for the UXM-E have the single-mode fiber (SMF), multimode fiber (MMF) and electrical connections. The cards are:

• BC-UAI-2-155-SMF
  
  
• BC-UAI-4-155-SMF
  
  
• BC-UAI-4-155-MMF
  
  
• BC-UAI-2-SMFXLR
  
  
• BC-UAI-4-SMFXLR
  
  
• BC-UAI-4-STM1E
  
  

As indicated by the "2" or the "4" in the model number, these cards have two or four transmit and receive connectors. Each line has a tri-color LED whose color indicates its status. Each card also has a red Fail LED and a green Active LED to indicate the status of the card. Table 4-12 lists the connectors and LEDs. Figure 4-11 shows the four-port OC3/STM1 card. The SMF, STM1E, SMFXLR, and MMF versions appear the same. Figure 4-12 shows the two-port OC3/STM1 card. For technical data on OC3/STM1 lines, see the appendix "System Specifications."

T3 Back Cards

The T3 back cards for the UXM-E are BC-UAI-6-T3 and BC-UAI-3-T3. These cards have six and three pairs of BNC connectors, respectively. Each port has a tri-color LED whose color indicates its status. Each card also has a red Fail LED and a green Active LED to indicate the status of the card. Table 4-13 lists the connectors and LEDs. Figure 4-13 show the six-port T3 card. Figure 4-14 shows the three-port T3 card. For technical data on T3 lines, see the appendix "System Specifications."

E3 Back Cards

The E3 back cards for the UXM-E are the six-port BC-UAI-6-E3 and the three-port BC-UAI-3-E3. These cards have six and three pairs of SMB connectors, respectively. Each line has a tri-color LED whose color indicates its status. Each card also has a red Fail LED and a green Active LED to indicate the status of the card. Table 4-14 lists the connectors and LEDs. Figure 4-15 show the six-port card. Figure 4-16 shows the three-port card. For technical data on E3 lines, see the appendix "System Specifications."

T1 Back Cards

The T1 back cards for the UXM-E are BC-UAI-8-T1-DB-15 and BC-UAI-4-T1-DB-15. These cards have eight and four DB-15 lines, respectively. Each line has a tri-color LED whose color indicates its status. If a card failure occurs, all the LEDs turn red. Table 4-15 lists the connectors and LEDs. Figure 4-17 show the eight-port T1 card. Figure 4-18 shows the four-port T1 card. For technical data on T1 lines, see the appendix "System Specifications."

E1 Back Cards

The E1 back cards for the UXM-E are:

• BC-UAI-8-E1-BNC
  
  
• BC-UAI-8-E1-DB-15
  
  
• BC-UAI-4-E1-BNC
  
  
• BC-UAI-4-E1-DB-15
  
  

As the model numbers indicate, the eight and four-port E1 cards can have either BNC or DB-15 connectors. Each line has a tri-color LED whose color indicates its status. If a card failure occurs on the back card, all LEDs turn red. Table 4-16 lists the connectors and LEDs. Figure 4-19 shows the card. Figure 4-20 shows the card. For technical data on E1 lines, see the appendix "System Specifications."

Network Trunk Module

The network trunk module (NTM) enables FastPacket transmission on a trunk. NTM functions include the following:

• Takes FastPackets off the cellbus and places them in queues before transmission to the trunk
  
  
• Arbitrates access to the trunk for the traffic type
  
  
• Monitors the age of each timestamped FastPacket, updates the timestamp for FastPackets at intermediate nodes, and discards FastPackets that exceed age limit
  
  
• Receives and checks FastPackets from the trunk and queues them for transmission to the cellbus
  
  
• Provides packet alignment based on the CRC in the FastPacket header
  
  
• Extracts clocking from the trunk that can be used as a clock source on the node or as a clock path
  
  
• Collects trunk usage statistics
  
  

An NTM can occupy any available front service card slot in the range 3 to 32. The choice of back card depends on the trunk interface type.

For fractional T1 trunk lines, the NTM and BC-T1 card set can provide the interface. A fractional trunk interface uses a group of 64-Kbps channels to create a partial T1 trunk. For example, a 512-Kbps fractional T1 trunk might use every third channel among channels 1 to 24. The user makes the channel assignments. For the clock rate, fractional trunks use the basic trunk frequency (such as 1.544 Mbps for T1).

Fractional E1 is the same as fractional T1 except that the channels are 1 to 15 and 17 to 31 (0 and 16 reserved), and the clock rate is 2.048 Mbps.

The NTM supports subrate trunks if a BC-SR back card and appropriate local bus are present. Subrate trunks interface to the transmission facility at rates in the range 64 Kbps to 2.048 Mbps. Three interface connections are possible: EIA/TIA-449, X.21, and V.35.

Y-Cable Redundancy for the NTM

You can configure the NTM for 1:1 redundancy by using a second, identical, card group in an adjacent slot and a Y-cable to connect the card sets. All NTM back cards support redundancy.

NTM Status

The faceplate of the NTM has four LEDs. The first two in the following list apply to the NTM front card. Each of the other two LEDs is a summary alarm for the back cards. Their significance is:

• The green Active LED indicates the NTM is active and functioning normally.
  
  
• The red Fail LED indicates an NTM card failure was detected.
  
  
• The yellow Minor LED indicates non-service-interrupting faults or statistical errors that have exceeded a preset threshold.
  
  
• The red Major LED indicates a service-affecting failure was detected.
  
  

The alarms and line conditions that the NTM monitors include those in the list that follows. To view errors on a trunk, use the dsptrkerrs command. To see a list of the (user-specified) errors that dsptrkerrs can display, use dsptrkstatcnf.

T1 Interface Card (BC-T1)

The T1 trunk interface card (BC-T1) card terminates a single 1.544 Mbps T1 trunk line on the NTM. The BC-T1 can reside in any rear slot 3 through 8 in an Cisco IGX 8410, 3 through 16 of the Cisco IGX 8420, or 3 through 32 of the Cisco IGX 8430. The BC-T1 connects directly to the NTM.

The BC-T1 supports two clock modes. The clock modes are normal clocking and loop timing. You select the mode through software control. With normal clocking, the node uses the receive clock from the network for the incoming data and supplies the transmit clock for outgoing data. The node can use the receive clock to synchronize itself with the network.

BC-T1 Faceplate Description

Figure 4-23 and Table 4-17 provide information on the faceplate of the BC-T1. When you correlate the descriptions in the table with the callouts in the figure, read from the top of the table to the bottom. The standard port connector is a female DB-15.

E1 Interface Back Card (BC-E1)

The E1 trunk interface card (BC-E1) provides an E1 trunk interface for the network trunk module (NTM). The BC-E1 connects directly to the NTM and can reside in any rear slot 3 through 8 in an Cisco IGX 8410, 3 through 16 in an Cisco IGX 8420, or 3 through 32 in an Cisco IGX 8430. The BC-E1 provides the following:

The BC-E1 supports two clock modes. The clock modes are normal clocking and loop timing. You select the mode through software control. With normal clocking, the node uses the receive clock from the network for the incoming data and supplies the transmit clock for outgoing data. The node can use the receive clock to synchronize itself with the network.

Statistics are kept on most line errors and fault conditions, including:

• Loss of signal
  
  
• Frame sync loss
  
  
• Multi-frame sync loss
  
  
• CRC errors
  
  
• Frame slips
  
  
• Bipolar violations
  
  
• Frame bit errors
  
  
• AIS, all-1's in channel 16 (CAS mode)
  
  

Figure 4-24 shows and Table 4-18 lists status LEDs and connections on the BC-E1 faceplate. When you correlate the table and figure items, read from the top to the bottom.

Subrate Interface Card (BC-SR)

The back card/subrate (BC-SR) terminates subrate trunks on the NTM. A subrate trunk uses part of the E1 or T1 bandwidth. The BC-SR typically functions in tail circuits or where little traffic exists.

A subrate trunk facility interface operates in DCE mode, and the subrate channel functions like a synchronous data channel. Therefore, the IGX BC-SR always operates in DTE mode. Only leased lines are supported (no dial-up lines). Subrate trunks cannot pass clock signals between nodes.The BC-SR provides the following:

Figure 4-25 and Table 4-19 describe the BC-SR faceplate. When you correlate the figure and table, read from the top down.

Table 4-20 lists the data signals and EIA leads supported by the subrate interface.

Figure 4-25: BC-SR Faceplate

Y1 Interface Back Card (BC-Y1)

The BC-Y1 back card provides a Japanese Y1 trunk interface for an NTM. The BC-Y1 can reside in any rear slot 3 through 8 in an Cisco IGX 8410, 3 through 16 in an Cisco IGX 8420, or 3 through 32 in an Cisco IGX 8430. The BC-Y1 provides:

• An interface to Japanese "Y" Trunk (Y1) lines
  
  
• Support for Y1 trunk formatted signaling
  
  
• Support for 24-channel, 1.544 Mbps operation
  
  
• Support for fractional rates
  
  
• Coded Mark Inversion (CMI) line coding
  
  
• Statistics for Y1 line events (such as loss of framing, loss of signal, and framing errors.)
  
  
• Support for local and remote loopback at the Y1 interface and the local bus interface for fault isolation
  
  

The BC-Y1 supports two clock modes. These are normal clocking and loop timing. The system operator selects the mode through software control. Normal clocking uses the receive clock from the network for incoming data and supplies the transmit clock for outgoing data. This clock can be used to synchronize the node.

Figure 4-26 and Table 4-21 provide descriptions of the BC-Y1 status LEDs and connections on the faceplate. When you correlate the items in the figure and table, read from the top to the bottom.

Posted: Sat Aug 31 17:59:24 PDT 2002
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