Table of Contents

Understanding Different Types of Fiber

Document Contents
Document Conventions
Site Requirements
Unpacking a Gigabit Ethernet SwitchProbe Device
Physical Features of Gigabit Ethernet SwitchProbe Devices

Front Panel

Chassis LEDs
Manual Reset Button
Interfaces

Gigabit Ethernet Interface LEDs
Ethernet Interface LEDs
Rear Panel

Power Sockets
Power Switch

Connecting a Gigabit Ethernet SwitchProbe Device
to the Network

Making a Connection to an Ethernet Interface
Making a Connection to a Gigabit Ethernet Interface

Connecting the Gigabit Ethernet Interface to a Cisco Catalyst-Series Switch SPAN Port
Connecting the Gigabit Ethernet Interface to a Full-Duplex Network Segment

Connecting a Gigabit Ethernet SwitchProbe Device
to a Power Source
Configuring a Gigabit Ethernet SwitchProbe Device

Selecting the Probe Mode
Changes to Aging Algorithm to Manage Non-Critical Nodes in Hosts and Conversations Tables
How the Aging Algorithm Operates

Technical Specifications
Cable Pinouts

Ethernet AUI Pin Designations
EIA/TIA-232 Console and Remote Serial Port Pin Designations

Cisco Connection Online

Cisco Gigabit Ethernet SwitchProbe Configuration Note

This document describes how to connect and configure Gigabit Ethernet SwitchProbe devices.

These devices collect statistical information from an attached Gigabit Ethernet network segment or from the switched port analyzer (SPAN) port on a Cisco Catalyst-series switch.

You can use a Gigabit Ethernet SwitchProbe device to monitor:

• A single full-duplex network segment, using a passive fiber optic splitter tap
  
  
• Any gigabit Ethernet port on up to two Cisco Catalyst-series switches
  
  

The device is available in three models supporting 1000BaseLX or 1000BaseSX gigabit Ethernet:

• 1000BaseLX multi-mode fiber (MMF)—Monitors long-haul (distances between 300 and 550 meters) multi-mode gigabit Ethernet fiber networks.
  
  

  This device supports only a multi-mode fiber optic splitter tap (to monitor a full-duplex network segment).

• 1000BaseLX single-mode fiber (SMF)—Monitors long-haul (distances of three kilometers) single-mode gigabit Ethernet fiber networks.
  
  

  This device supports only a single-mode fiber optic splitter tap (to monitor a full-duplex network segment).

• 1000BaseSX multi-mode fiber (MMF)—Monitors short-haul (distances between 300 and 550 meters) gigabit Ethernet multi-mode fiber networks.
  
  

  This device supports only a multi-mode fiber optic splitter tap (to monitor full-duplex networks).

Understanding Different Types of Fiber

Multi-mode fiber supports the propagation of multiple frequencies. Single-mode fiber has a higher bandwidth than multi-mode fiber, but requires a light source (such as a laser) with a narrow spectral width.

Depending on the type of cable used (MMF or SMF) and the distance the signal is transmitted, different laser types (LX or SX) may be used.

• The short-wave 1000BaseSX laser works on multi-mode fiber typically used in buildings.
  
  
• The more powerful 1000BaseLX laser is designed for use in longer, single-mode fiber in campus and small metropolitan networks for distances up to three kilometers, although it can be used with multi-mode fiber for shorter distances.
  
  

Document Contents

This document includes the following sections:

• Document Conventions
  
  
• Site Requirements
  
  
• Unpacking a Gigabit Ethernet SwitchProbe Device
  
  
• Physical Features of Gigabit Ethernet SwitchProbe Devices
  
  
• Connecting a Gigabit Ethernet SwitchProbe Device to the Network
  
  
• Connecting a Gigabit Ethernet SwitchProbe Device to a Power Source
  
  
• Configuring a Gigabit Ethernet SwitchProbe Device
  
  
• Technical Specifications
  
  
• Cable Pinouts
  
  
• Cisco Connection Online
  
  

Document Conventions

Command descriptions use the following conventions:

Screen examples use the following conventions:

Notes use the following conventions:

Cautions use the following conventions:

Caution Means reader be careful. In this situation, you might do something that could result in equipment damage or loss of data.

Warnings use the following conventions:

Warning This warning symbol means danger. You are in a situation that could cause bodily injury. Before you work on any equipment, you must be aware of the hazards involved with electrical circuitry and familiar with standard practices for preventing accidents. To see translated versions of the warnings, refer to the translated safety warnings appendix in the Cisco SwitchProbe Installation and Configuration Guide.

Site Requirements

The SwitchProbe device is designed to operate in a normal office environment and can be placed on a table, or mounted in an equipment rack near the network segment it serves. The site must be equipped with the following:

• A power source within seven feet (2.133 m) of the unit
  
  

Warning This product relies on the building's installation for short-circuit (overcurrent) protection. Ensure that a fuse or circuit breaker no larger than 120 VAC, 15A U.S. (240 VAC, 10A international) is used on the phase conductors (all current-carrying conductors).

• The appropriate physical connection to the network link to be monitored
  
  
• The appropriate physical connection to the network segment used to communicate with the management software such as an Ethernet or EIA/TIA-232 connection
  
  

---

Note EIA/TIA-232 and EIA/TIA-449 were known as recommended standards RS-232 and RS-449 before their acceptance as standards by the Electronics Industries Association (EIA) and Telecommunications Industry Association (TIA).

---

Before beginning the installation process, read the following installation cautions and warnings:

---

Note To see the warnings in multiple languages, refer to the translated safety warnings appendix in the Cisco SwitchProbe Installation and Configuration Guide.

---

Caution To prevent possible damage to the device, read the section "Site Requirements" in this document.

Warning The safety cover is an integral part of the product. Do not operate the unit without the safety cover installed. Operating the unit without the cover in place will invalidate the safety approvals and pose a risk of fire and electrical hazards.

Warning Read the installation instructions before you connect the system to its power source.

Warning Only trained and qualified personnel should be allowed to install, replace, or service this equipment.

Warning Ultimate disposal of this product should be handled according to all national laws and regulations.

Warning The device is designed to work with TN power systems.

Warning Before working on a system that has an on/off switch, turn OFF the power and unplug the power cord.

Warning To prevent the device from overheating, do not operate it in an area that exceeds the maximum recommended ambient temperature of 104° F (40° C). To prevent airflow restriction, allow at least 3 inches (7.6 cm) of clearance around the ventilation openings.

Warning To prevent bodily injury when mounting or servicing this unit in a rack, you must take special precautions to ensure that the system remains stable. The following guidelines are provided to ensure your safety:

• This unit should be mounted at the bottom of the rack if it is the only unit in the rack.
  
  
• When mounting this unit in a partially filled rack, load the rack from the bottom to the top with the heaviest component at the bottom of the rack.
  
  
• If the rack is provided with stabilizing devices, install the stabilizers before mounting or servicing the unit in the rack.
  
  

Unpacking a Gigabit Ethernet SwitchProbe Device

Before unpacking the shipping carton, ensure that there is no visible damage to the carton. If there is damage, notify the carrier representative, and arrange for a representative to be present while you unpack the carton.

Physical Features of Gigabit Ethernet SwitchProbe Devices

This section describes the physical features of Gigabit Ethernet SwitchProbe devices.

Gigabit Ethernet SwitchProbe devices are housed in rack-mountable, front-access chassis that measures 17 inches wide, by 16.5 inches deep, by 5.25 inches high (43.18cm wide by 41.91cm deep by 13.34cm high). You can mount these devices in a 19-inch equipment rack. For instructions on mounting the device in a rack, see the installation chapter in the Cisco SwitchProbe Installation and Configuration Guide.

The following sections describe each area of the Gigabit Ethernet SwitchProbe devices:

• Front Panel
  
  
• Rear Panel
  
  

Front Panel

Figure 1 shows the front panel of the Gigabit Ethernet SwitchProbe 1000BaseLX model. Figure 2 shows the front panel of the Gigabit Ethernet SwitchProbe 1000BaseSX model.

• Chassis LEDs
  
  
• Manual Reset Button
  
  
• Interfaces
  
  
• Gigabit Ethernet Interface LEDs
  
  
• Ethernet Interface LEDs
  
  

Chassis LEDs

Table 1 describes the four LEDs on the top left of the chassis front panel.

Manual Reset Button

There is a small pin hole (Figure 1) to the left of the LEDs that provides access to the manual reset button. To manually reboot the device, insert a small object such as the tip of a pen, and push inward. A slight press of the manual reset button reboots the device.

Interfaces

The following sections describe the interfaces on the Gigabit Ethernet 1000BaseLX and 1000BaseSX SwitchProbe devices:

• Network Interface Cards
  
  
• Peripheral Controller Card
  
  

Network Interface Cards

  For information about the Agent Configuration Utility, see the initialization chapter in the Cisco SwitchProbe Installation and Configuration Guide, or the section "Configuring a Gigabit Ethernet SwitchProbe Device" in this document.

• Gigabit Ethernet NIC—The Gigabit Ethernet NIC contains two physical ports. There are two logical interface configurations:
  
  
• Two physical (and two logical) interfaces for half-duplex
  
  
• Two physical (and one logical) interfaces for full-duplex
  
  

  The number of ports you use (described in Tables 2 and 3) varies according to the mode (half- or full-duplex). For more information about the mode, see "Selecting the Probe Mode." The Gigabit Ethernet interface is always in monitor mode.

Table 2 describes the interfaces on Gigabit Ethernet SwitchProbe 1000BaseLX models.

Table 3 describes the interfaces on the Gigabit Ethernet SwitchProbe 1000BaseSX model.

Peripheral Controller Card

• Remote Port—Serial Line Internet Protocol (SLIP) port. This 9-pin, male, D-type connector supports RS-232 signals. The port specifications are listed in Table 4.
  
  

  The remote port can only be used to exchange management data to and from an attached device such as a management station or a modem. You must configure the remote port to manage mode. The remote port can be the secondary management port if communication to the primary management port is lost.

---

Note The remote port cannot be used to monitor a network segment.

---

To adjust the baud rate of the remote port, see the Cisco SwitchProbe Installation and Configuration Guide.

Table 4 shows the console and remote port specifications.

  
Table 4: Console and Remote Port Specifications

Port Setting	Specification
Line rate	9600 bps (default)
Line code	ASYNC
Line interface	EIA/TIA-232
No. of bits	8
No. of stop bits	1
Parity	None

• Console Port—Configuration port. This 9-pin, male, D-type connector supports RS-232 signals.
  
  

  To configure a SwitchProbe device (set IP address, subnet mask, and default gateway address) using an ASCII terminal, you must connect that terminal to the console port. For more information about configuring the SwitchProbe device through an ASCII terminal, see the initialization chapter in the Cisco SwitchProbe Installation and Configuration Guide.

  Use a null-modem cable to connect the console port to an ASCII terminal. A sample wiring diagram of a null-modem crossover cable is provided in "Cable Pinouts."

• DIP Switches (SW1)—Configurable DIP switches (labeled SW1) between the console and remote ports used for adjusting the baud rate of the console port and setting the device's boot mode.
  
  
• Switch 1—Specifies whether the device boots from FLASH memory or erasable programmable read-only memory (EPROM).
  
  
• Switch 2—Not used.
  
  
• Switches 3 and 4—Specifies the console port baud rate.
  
  

If the raised portion of the switch is to the left, the switch is on. If the raised portion of the switch is to the right, the switch is off.

  Table 5 shows the DIP switch settings.

  
Table 5: DIP Switch Settings

Switch	Setting	Result
1	Off (default) On	Boot from FLASH memory Boot from EPROM
2	Off (default)	Reserved
3, 4	3 = off 4 = off	Console port = 1200 bps
	3 = off 4 = on	Console port = 2400 bps
	3 = on (default) 4 = off (default)	Console port = 9600 bps
	3 = on 4 = on	Console port = 19200 bps

Gigabit Ethernet Interface LEDs

Each Gigabit Ethernet interface contains seven LEDs:

• The top 3 LEDs represent port 1.
  
  
• The bottom 3 LEDs represent port 2.
  
  
• The solitary LED indicates whether the interface is functioning.
  
  

Table 6 describes the Gigabit Ethernet interface LEDs.

Figure 3 shows the Gigabit Ethernet interface LEDs.

Ethernet Interface LEDs

The Ethernet interface contains two LEDs, described in Table 7.

Figure 4 shows the Ethernet interface LEDs.

Rear Panel

Figure 5 shows the rear panel of a Gigabit Ethernet SwitchProbe device.

• Power Sockets
  
  
• Power Switch
  
  

Power Sockets

There are two power sockets on the rear panel of the Gigabit Ethernet SwitchProbe device:

• The upper power socket is the Power In socket—Has three small metal prongs.
  
  
• The lower power socket is the Power Out socket—Has no metal prongs.
  
  

Caution To prevent damage to the device, and to ensure that it operates correctly, never use the Power Out socket.

Each Gigabit Ethernet SwitchProbe device is equipped with an AC power cord for connection to an appropriate power source. To connect the device to a power source, see "Connecting a Gigabit Ethernet SwitchProbe Device to a Power Source."

Power Switch

The power switch is on the upper right of the rear panel of the device. To turn on the power, press the (|) side of the button until it is flush with the rear panel. To turn off the power, press the (0) side of the button until it is flush with the rear panel.

Caution To avoid damaging the device, you cannot turn the power off for four seconds after you turn the power on.

Connecting a Gigabit Ethernet SwitchProbe Device
to the Network

Before connecting this device to the network, note the following warnings:

Warning This equipment is to be installed and maintained by service personnel only as defined by AS/NZS 3260 Clause 1.2.14.3 Service Personnel.

Warning The telecommunications lines must be disconnected 1) before unplugging the main power connector and/or 2) while the housing is open.

Warning Do not work on the system or connect or disconnect cables during periods of lightning activity.

To connect a Gigabit Ethernet SwitchProbe device to the network segment, see the following sections:

• Making a Connection to an Ethernet Interface
  
  
• Making a Connection to a Gigabit Ethernet Interface
  
  

Making a Connection to an Ethernet Interface

The Ethernet interface supports either Thicknet, Thinnet, or unshielded twisted pair (UTP) cable types; the device is set to one of the three types during manufacture. A label in the lower portion of the device front panel indicates the factory-set configuration.

Table 8 describes the label and corresponding connection.

Making a Connection to a Gigabit Ethernet Interface

The way you connect the Gigabit Ethernet interface to a network segment depends on the type of segment to be monitored.

• Monitoring half-duplex network segments—You can connect the network segment directly to the SwitchProbe device. To do so, see "Connecting the Gigabit Ethernet Interface to a Cisco Catalyst-Series Switch SPAN Port."
  
  
• Monitoring full-duplex network segments—You must use the fiber optic splitter tap that is shipped with the device.
  
  

Connecting the Gigabit Ethernet Interface to a Cisco Catalyst-Series Switch SPAN Port

Some switches (such as the Cisco Catalyst 4000-, 5000, and 6000-families) have an auto-negotiate mode that allows a port on the switch to automatically negotiate the speed and mode (half- or full-duplex) of the device on the other side of the network segment. If the other side of the segment (for example, the Gigabit Ethernet SwitchProbe device) does not respond to the auto-negotiation, the switch assumes that there is no device at the other end, and shuts off the internal link.

Because this SwitchProbe device is designed to work in receive-only mode, it does not participate in any auto-negotiation in half-duplex mode. Therefore, the switch assumes there is no device attached to the other end of the network segment—even though the Gigabit Ethernet SwitchProbe device is physically attached to the switch SPAN port.

To work around this, you must disable auto-negotiation on the port to which the Gigabit Ethernet SwitchProbe device is physically connected.

For example, with a Cisco Gigabit Ethernet switch, you would enter the following command on the switch command line:

set port negotiation module_num/port_num disable

where module_num/port_num identifies the port on the switch that is connected to the Gigabit Ethernet SwitchProbe device.

This situation occurs only when a Gigabit Ethernet SwitchProbe device is directly attached (with no tap) to a Cisco Catalyst-series switch SPAN port.

To connect the Gigabit Ethernet interface to a Cisco Catalyst-series switch, see Figure 6 and follow these steps:

Step 1   Locate an SC-to-SC fiber cable (with one male SC connector at each end) that was included with the SwitchProbe device.

Step 2   Remove all dust caps from the connectors at the ends of the cable.

---

Note Save these dust caps for future use.

---

Step 3   Plug one end of the SC-to-SC fiber cable into the Gigabit Ethernet switch, server, or router to be monitored.

Step 4   Plug the other end of the cable into one of the Gigabit Ethernet interface ports on the SwitchProbe device.

Connecting the Gigabit Ethernet Interface to a Full-Duplex Network Segment

Connecting the Gigabit Ethernet interface to a full-duplex network segment is a two-stage process:

Step 1   Connecting the fiber optic splitter tap (shipped with the device) to the Gigabit Ethernet interface on the SwitchProbe device.

Step 2   Connect two Gigabit Ethernet devices to the fiber optic splitter tap (to accumulate statistics about data as it travels on the network segment).

Connecting the Fiber Optic Splitter Tap to the SwitchProbe Device

To connect a fiber optic splitter tap to the SwitchProbe device, see Figure 7 and follow these steps:

Step 1   Remove all dust caps from the fiber optic splitter tap connector ports.

---

Note Save these dust caps for future use.

---

Step 2   Locate the 9.84 foot (3 meter) fiber cable (with two male SC connectors at one end and one male SC connector at the other end) that was included with the tap.

Step 3   Remove all dust caps from the connectors at the ends of the cables.

---

Note Save these dust caps for future use.

---

Step 4   Plug the end of the fiber cable (labelled DCE) into port 1 of the Gigabit Ethernet interface (port 1 is the DCE port).

Step 5   Plug the end of the fiber cable (labelled DTE) into port 2 of the Gigabit Ethernet interface (port 2 is the DTE port).

Step 6   Plug the other end of the fiber cable (the one with a single connector) into the port labelled Probe on the fiber optic splitter tap.

Connecting a Fiber Optic Splitter Tap to a Network Segment

To do so, see Figure 8 and follow these steps:

Step 1   Locate the cable that currently connects one Gigabit Ethernet switch, server, or router to another Gigabit Ethernet switch, server, or router.

Step 2   Unplug this cable from one of the two Gigabit Ethernet devices.

Step 3   Plug the end of the cable (that you just unplugged) into the one of the two remaining female SC duplex ports on the tap (either port A or B).

Step 4   Locate an SC-to-SC fiber cable (with one male SC connector at each end).

---

Note A 24-foot (7.32 meter), multi-mode cable is shipped with each multi-mode fiber optic splitter tap.

A 9.84-foot (3 meter), single-mode cable is shipped with each single-mode fiber optic splitter tap.

---

Step 5   Plug one end of the SC-to-SC fiber cable into the second Gigabit Ethernet switch, server, or router.

Step 6   Plug the other end of the cable into the remaining female SC duplex port on the tap (A or B).

As illustrated in Figure 8, there should now be one cable extending from one Gigabit Ethernet switch, server, or router to the tap A port, and another cable from another Gigabit Ethernet switch, server, or router to the tap B port, and the tap should be connected to the SwitchProbe device.

Connecting a Gigabit Ethernet SwitchProbe Device
to a Power Source

To connect a Gigabit Ethernet SwitchProbe device to a power source, follow these steps:

Step 1   Using the AC power cord included with the device, connect one end of the cord to the Power In socket.

Warning This equipment is intended to be grounded. Ensure that the host is connected to earth ground during normal use.

Step 2   Connect the other end of the AC power cord to a suitable power source.

Caution To prevent any possible damage to the device, and to ensure that it operates correctly, never use the Power Out socket.

Configuring a Gigabit Ethernet SwitchProbe Device

The Cisco SwitchProbe Installation and Configuration Guide (shipped with all Cisco SwitchProbe devices) explains the basic configuration process. Read and follow the instructions in that guide to configure the agent firmware in your SwitchProbe device.

Selecting the Probe Mode

When you choose Select Probe Mode from the Agent Configuration Utility main menu (selection 23), two options (half- and full-duplex) are displayed in another menu. You use these options to set the mode on the Gigabit Ethernet NIC. The default value is full-duplex (1).

To select the mode, follow these steps:

Step 1   From the Select Probe Mode menu, enter the option number (1 for half-duplex or 0 for full-duplex) and press Enter.

The Agent Configuration Utility main menu is displayed.

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Note The new value does not take effect until you reset the agent.

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Step 2   Enter the number listed to the left of the Reset Agent menu option and press Enter.

For more information about resetting the agent, see the Cisco SwitchProbe Installation and Configuration Guide.

Changes to Aging Algorithm to Manage Non-Critical Nodes in Hosts and Conversations Tables

In earlier releases of the agent firmware, the aging algorithm would age out (delete) host and conversation entries when the aging_interval had elapsed. If a host table was full, no additional hosts would be counted until the next time the aging_interval elapsed.

The aging algorithm in the Gigabit Ethernet SwitchProbe device firmware has been modified to manage noise (non-critical) nodes in the hosts and conversation tables, freeing up space in the host and conversation tables. By doing so, the host and conversation tables can contain the more critical host and conversation data.

To implement the modified aging algorithm, you must assign values to three aging parameters:

• min_aging
  
  
• age_check_interval
  
  
• noise_threshold
  
  

How the Aging Algorithm Operates

The removal of any node from the host or conversation table occurs only when one of these conditions exists:

• The node has not seen any data in or out in the past min_aging period.
  
  
• At every age_check_interval, the node has consistently seen an amount of data during each min_aging period that is less than the noise_threshold.
  
  

For example, if the aging parameters are set to the following values, and the node sends a ping packet every 300 seconds, the node is initially seen in the host table:

• min_aging—10800 seconds
  
  
• age_check_interval—300 seconds
  
  
• noise_threshold—3000 bytes per age_check_interval
  
  

However, because the node does not send more than 3000 bytes during a 300-second interval, upon reaching the min_aging period of 10800 seconds (three hours), the node is deleted from the host table.

If, after one hour, the same node sends an FTP data packet at a rate of 10,000 bytes in 300 seconds, then resumes a ping process at a rate of 64 bytes every 300 seconds—but during the next three hour period sees data at a rate that is less than 3,000 bytes in a 300-second interval—then, upon reaching the min_aging period of 10800 seconds (three hours) since the FTP data packet passed through, the node is deleted from the host table.

The noise_threshold check determines whether any node has sustained minimum traffic within the min_aging period.

Table 9 describes the aging parameters.

Technical Specifications

Table 10 lists technical specifications for the Gigabit Ethernet SwitchProbe device.

Standards compliance for all SwitchProbe devices is as follows:

• Compliance—CE Marking
  
  
• Safety—UL1950, CAN/CSA-C22.2, No. 950-95, EN 60950, and IEC 60950
  
  
• EMI—FCC Class A, EN 55022 Class A, and VCCI Class A
  
  

Cable Pinouts

The following sections describe the cable pinouts:

• Ethernet AUI Pin Designations
  
  
• EIA/TIA-232 Console and Remote Serial Port Pin Designations
  
  

Ethernet AUI Pin Designations

Table 11 describes the pin designations for the Ethernet AUI Interface.

EIA/TIA-232 Console and Remote Serial Port Pin Designations

Table 12 shows the EIA/TIA-232 pin designations for the console and remote serial ports.

Cisco Connection Online

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Available 24 hours a day, 7 days a week, CCO provides a wealth of standard and value-added services to Cisco's customers and business partners. CCO services include product information, product documentation, software updates, release notes, technical tips, the Bug Navigator, configuration notes, brochures, descriptions of service offerings, and download access to public and authorized files.

CCO serves a wide variety of users through two interfaces that are updated and enhanced simultaneously: a character-based version and a multimedia version that resides on the World Wide Web (WWW). The character-based CCO supports Zmodem, Kermit, Xmodem, FTP, and Internet e-mail, and it is excellent for quick access to information over lower bandwidths. The WWW version of CCO provides richly formatted documents with photographs, figures, graphics, and video, as well as hyperlinks to related information.

You can access CCO in the following ways:

• WWW:  http://www.cisco.com
  
  
• WWW:  http://www-europe.cisco.com
  
  
• WWW:  http://www-china.cisco.com
  
  
• Telnet:  cco.cisco.com
  
  
• Modem:  From North America, 408 526-8070; from Europe, 33 1 64 46 40 82. Use the following terminal settings: VT100 emulation; databits: 8; parity: none; stop bits: 1; and connection rates up to 28.8 kbps.
  
  

For a copy of CCO's Frequently Asked Questions (FAQ), contact cco-help@cisco.com. For additional information, contact cco-team@cisco.com.

Posted: Fri Sep 6 20:20:36 PDT 2002
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