CentreCOM AT-4016TR AT-4016F AT-TS95TR Ethernet Switch with ATM Access AT-S13 AT-S14 AT-S16 Release 2.
Copyright 1996 Allied Telesyn International Corporation All rights reserved. No part of this publication may be reproduced without prior written permission from Allied Telesyn International Corporation. Allied Telesyn International Corporation reserves the right to make changes in specifications and other information contained in this document without prior written notice. The information provided herein is subject to change without notice.
Table of Contents Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii Assumptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Table of Contents Chapter 2 Getting Started . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Getting Started — Omega. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10 Omega Main Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Individual Port Graph — Frames . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Error Statistics Menu. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . System Overview . . . . . . . . . . . . . . . . . . . . . .
Table of Contents Appendix B LAN Emulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .111 LANE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113 Components of LANE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Preface Background This document represents a discussion of the software operating systems of Allied Telesyn International’s (ATI’s) AT-4016TR (or AT-4016F) Ethernet Switch With ATM Access which uses the optional AT-S13 or AT-S14 PCMCIA Firmware Card (Version 2.2) and the AT-TS95TR TurboStack Switch With ATM Access and Management which uses the optional AT-S16 Firmware Cassette (Version 2.2).
Preface Contents The contents of each chapter are described below. ❑ Chapter 1, “Product Description” introduces an overview of functions and features. ❑ Chapter 2, “Getting Started” describes how an experienced user can quickly and easily configure an ATM network. ❑ Chapter 3, “Ethernet Administration” tells you how to use ATI’s Omega management Ethernet software. ❑ Chapter 4, “ATM Administration” tells you how to configure, monitor and manage an ATM network.
Operations Manual Related Documentation You may find the following networking reference material helpful: ❑ Internetworking with TCP/IP: Principles, Protocols, and Architecture (2nd edition), Volumes I and II, Douglas Comer, Prentice Hall © 1991. ❑ Interconnections, Bridges and Routers, Radia Perlman, Addison Wesley © 1992. ❑ The Simple Book, An Introduction to Management of TCP/IP-based internets, Marshall T. Rose, Prentice Hall © Second Edition, 1994.
Preface Contacting ATI Technical Support Problems? Questions can be directed to ATI’s Technical Support staff by: ❑ Telephone ❑ Bulletin board services ❑ Electronic mail via the Internet ❑ CompuServe forum ❑ World Wide Web When you contact Technical Support, you should have the following information available: Phone Numbers ❑ Firmware Revision number ❑ Complete description of the problem including any observed errors ❑ Complete configuration information ❑ Serial number of your switch ❑
Operations Manual FTP Server World Wide Web Allied Telesyn has Internet access to an FTP Server in Bothell, WA., for driver and Readme files on our adapter cards and managed products. The server can be accessed through your Internet connection as follows (note — use lower case letters): Address gateway.centre.
Preface xii
Chapter 1 Product Description Overview Welcome to Allied Telesyn International! Allied Telesyn’s AT-4016TR Ethernet Switch With ATM Access, AT-4016F Ethernet Switch With ATM Access and AT-TS95TR TurboStack Switch With ATM Access and Management are all Ethernet-to-Ethernet and Ethernetto-ATM switches. All support 10 Mbps of dedicated bandwidth on 16 (AT-4016TR and AT-4016F) or 8 (AT-TS95TR) IEEE 802.3 Ethernet ports.
Product Description Features The following features are fully implemented: ❑ An Ethernet switch combined with ATM connectivity ❑ User defined emulated LAN support (up to 64 ELANs) either by port or MAC address ❑ Software upgrading and downloading using TFTP or the optional PCMCIA Firmware Card (AT-S13 and AT-S14) for the AT-4016TR as well as the AT-4016F/SC and the AT-4016F/ST ❑ Software upgrading and downloading using TFTP or the optional Firmware Cassette (AT-S16) for the AT-TS95TR ❑ Simple Netw
Operations Manual Figure 1 shows the front panel of an AT-4016TR. It is presented as a review of the positioning of the relevant ports.
Product Description Figure 4 shows the rear panel of an AT-TS95TR. Firmware Cassette Port Backplane Figure 4: AT-TS95TR Rear Panel Standards Compliance The ATI implementation of LAN Emulation (LANE) services is compliant with the following existing standards: ❑ ATM Forum LAN Emulation specification version 1.0 ❑ ATM Forum UNI specification version 3.0 Note that a full discussion of the interactive components of LANE can be found in Appendix B, LAN Emulation.
Operations Manual Management Information Base Protocols LAN Emulation The following Management Information Bases (MIBs) are supported. An expanded discussion of selected MIB support is provided in Appendix C.
Product Description Interim Local Management Interface (ILMI) There is a MIB in the User-Network Interface (UNI) specification, ILMI, which includes sufficient “managed objects” to allow you to control and configure ATM nodes and terminals. As you will recall, the UNI simply consists of ATM Forum-developed specifications which define the procedures and protocols between a user and the ATM network. ILMI is a link-level management and configuration protocol defined across the UNI.
Operations Manual Bridging Your switch operates as a transparent bridge to the Ethernet ports. As such, it learns the source Media Access Control (MAC) addresses of all incoming packets and ages out devices which have not been heard from for either a user or the default-specified length of time. The switch maintains a forwarding table with a maximum storage capacity of 2,048 MAC address. These Ethernet addresses are associated with all of the devices that have been detected recently.
Product Description Spanning Tree Protocol The IEEE 802.1d Spanning Tree Protocol (STP) is both a configuration algorithm and a protocol. As it is fully presented in Chapter 5, you are referred to that discussion.
Chapter 2 Getting Started — The Basics A completely functional ATM network requires the successful integration of several disparate units: An AT-4016TR or AT-4016F Ethernet-to-ATM switch, or An AT-TS95TR Ethernet-to-ATM switch ATI’s Omega management software which is provided An optional ATM-to-ATM Switch An optional ATM Configuration Server (LECS) Getting started involves the following sequence: 1. Omega management software.
Getting Started — The Basics Getting Started — Omega ATI’s Omega management software is pre-installed and immediately operational once power is applied. Configuring you network depends, however, upon the requirements of your particular environment. Your switch can operate either standalone when the backbone port is not connected to an ATM network — or as an Ethernet switch/ATM Emulated LAN when the backbone port is connected to an ATM network and functioning.
Operations Manual AT-S13/AT-S14 Main Menu The Main menu of an AT-4016TR switch is shown below. NOTE The use of the Port, Frame and Error statistics submenus are specifically associated with Ethernet functionality and discussed in Chapter 3, Ethernet Administration. Since they are not used to actually configure an ELAN, they will not be presented here.
Getting Started — The Basics AT-S16 Main Menu The AT-TS95TR Main menu is identical to the AT-4016TR except for the header. It is shown below. Parameter Changes The parameter changes listed below require the system to be reset before they are recognized.
Operations Manual System Administration Menu The following Omega Menu Map summarizes the functions that are available under the System Administration menu.
Getting Started — The Basics From the Main menu, open Omega’s System Administration submenu by entering the letter S from the Main Menu. The contents and features of this submenu are shown below.
Operations Manual System Name From the System Administration submenu, enter the letter S for System name. The following submenu can be used to enter or change the name of your switch. You may enter a new name, up to 20 characters in length, or press RETURN to keep the existing symbolic name. To delete an existing name, enter one or more space characters (blanks) and then press RETURN.
Getting Started — The Basics Password, Timeout To assign or change the password or timeout value, return to the System Administration submenu and enter the letter P for the Password, timeout submenu: Password. Password protection restricts unauthorized access to Omega management. This is a very different type of password protection than “Download Password” which is found within the IP parameters submenu and discussed later.
Operations Manual Timeout. From the Password screen, press for the Timeout screen. Timeout may be useful to avoid connection problems due to multiple sessions (for example, you may start a local session and not exit the system before attempting a Telnet session later). Your switch allows one management session at a time. The timeout option will automatically end the session if there is no activity for the length of time you have specified (in minutes).
Getting Started — The Basics IP Parameters Menu You must choose a protocol for your network: Is it to be a TCP/IP or a nonTCP/IP network? TCP/IP Network Management If you have many geographically dispersed subnetworks, each connected to its own department concentrator, you may want to manage these multiple hubs remotely in a central-site configuration. In this case, TCP/IP network management may be optimum. TCP/IP internet addresses consist of user assigned numbers which identify members of the network.
Operations Manual If a BootP response is received, then the IP address, Subnet Mask, and/or Gateway/Router address will be extracted from the response packet and used to configure the system until the next power-on/reset. Although the BootP server file format differs from server to server, your switch nevertheless expect a response packet to contain an IP address, Subnet Mask and Gateway address.
Getting Started — The Basics Enter the letter I for IP parameters to access the following submenu: Choose those parameters you want to change by simply entering A for IP address, B for subnet mask, C for gateway address or D through G for manager addresses. A minimal configuration requires only an IP address and Subnet mask.
Operations Manual Setting an IP Address for Telnet The IP parameters submenu can be used to set the IP address, Subnet mask and Gateway address for Telnet. 1. Set the Manager address in the IP submenu. Enter D through G for a selection of up to four manager addresses and enter the IP address of the SNMP management server. Press RETURN to save the new address. 2. Set the ‘Get’ community string. Enter I and the string value. Press RETURN to save the new value. 3. Set the ‘Set’ community string.
Getting Started — The Basics 22
Chapter 3 Ethernet Administration Accessing Omega To start a session with the management agent, either: 1. Press the key twice on a PC connected to the RS232 port, or 2. If your switch has been assigned an IP address, use Telnet to access the management agent. A session begins when either of the above events occur. Once in session, the management agent and the Statistical Database program are “locked” against other session requests. This prevents unwanted simultaneous access to the database.
Ethernet Administration Some of the submenus cannot fit on a single screen. In this case follow the instructions on the screen to obtain additional information or to go to the next page. AT-S13/AT-S14 Port Status Screen Choose the AT-S13 (or AT-S14) Port Status submenu by entering the letter P. The system will then display the screen shown below. This screen shows the status and configuration of each Ethernet port. At the top of the screen, you see the system name (if any).
Operations Manual Status. The Status column basically shows whether the port participates, or does not participate, in the transmission and/or reception of frames or, more exactly, Bridge Protocol Data Units (BPDUs) which is defined as a data unit transmitted as part of the STP algorithm. The exchange of BPDUs allows bridges within a network to logically configure the network as a single spanning tree.
Ethernet Administration Polarity. The Polarity column shows the state of each UTP port’s receive pair polarity: either Normal or Reversed. Normal indicates correct polarity. Reversed indicates incorrect polarity — software has detected that your wiring has been installed with reversed polarity. It has also subsequently corrected it. Operator intervention is not required. AT-S16 Port Status Screen Choose the AT-S16, AT-TS95TR, Port Status screen.
Operations Manual The Changing Port Configuration screen allows you to modify the Management Software default configuration settings. AT-S13/AT-S14 Port Configuration Screen To change port information, enter a port number from the Port Status menu. The Port Configuration Menu for the AT-S13 appears. In this case, port #4 was selected. The system and port name appear at the top of the screen. Below that is the port’s status and configuration. And, below that, you see several menu options.
Ethernet Administration Change port name. The option Change port name allows you to specify a new symbolic name for the port or change an existing one. If selected, the following screen appears: You can enter a new name for the port, up to 20 characters in length, or press RETURN to keep the existing name (if any). To delete an existing name, enter one or more space characters (blanks) and then press RETURN.
Operations Manual AT-S16 Port Configuration Screen The Port Configuration Menu for the AT-S16 follows. It is identical to the AT-S13/AT-S14 screen except for the Interface feature. In this case, port #1 was selected. Interface Autosense. Only one connection at a time may be made to any port in the AT-TS95TR switch. The first six ports (ports 1 through 6) have two possible connections: front Panel and Segmented Backplane. This potential conflict is resolved with Interface Autosense logic.
Ethernet Administration Ethernet Parameters Choose the System Administration submenu. The following Omega Menu Map (see Table 3) summarizes the functions that are available under the System Administration menu.
Operations Manual Enter the letter E for Ethernet parameters to access the following submenu: NOTE All changes to Ethernet parameters require a system reset to be activated. Your switch offers the choice of store-and-forward (the default) or cut-through switching strategies. In store-and-forward, the switch stores the entire packet before it is forwarded. The Ethernet parameters screen shows the current choices for forwarding and for LED modes of operation. At the bottom you see a list of menu options.
Ethernet Administration Terminal Configuration Choose the System Administration submenu. Enter the letter T for Terminal Configuration to access the following submenu: Presently configured (or default) options are highlighted with an arrowhead (“>”). Changes to the configured terminal characteristics (terminal type and half/ full duplex) take effect immediately. For example, changing from half duplex to full duplex will cause the management agent to begin echoing your input immediately.
Operations Manual Generic—The Generic terminal option configures the management agent for the lowest common denominator terminal. In this configuration, the management agent makes very few assumptions about the terminal’s capabilities and is compatible with almost all terminals. Custom Terminal Configuration—Custom terminal definition... enables the same full-screen display characteristics as the ANSI option, but with a non-ANSI terminal. If you select the Custom terminal definition...
Ethernet Administration Under Custom Terminal Configuration... the first sequence to be configured is HOME THE CURSOR. This is followed by the ERASE THE ENTIRE SCREEN.
Operations Manual Finally, you enter the ERASE TO END-OF-LINE. Data Rate—Return to the Terminal Configuration screen and select Data rate (baud” rate).... The screen consists of selectable baud rates. If you select Automatic baud rate detection, you will have to press RETURN twice to begin future management agent sessions. Two RETURNs are required in order to determine the terminal’s actual data rate.
Ethernet Administration Update Software In Another System There are two prerequisites before you can update software to another system: 1. Software cannot be upgraded if either an AT-S13/AT-S14 PCMCIA card or an AT-S16 Firmware Cassette is installed in the remote device, and 2. All systems must have the same downloaded password. Return to the System Administration submenu. Enter the letter U for Update software in another system. The following submenu will be displayed.
Operations Manual Broadcast Updated Software To All Systems Choose the System Administration submenu. Enter the letter B for Broadcast updated software to all systems. A message is broadcast to all other Allied Telesyn switches informing them that software is to be downloaded if they are not already running the current software release (the software running on the hub from which you issued this command is, by definition, the current software release).
Ethernet Administration Activity Monitor This option is used for troubleshooting purposes as well to indicate the completion of downloaded software. Further, technical support personnel have the ability to retrieve this information and, subsequently, use it towards the determination and resolution of problems. Open the System Administration menu and enter the letters AC for the Activity monitor. This option displays a variety of messages showing system activity as it occurs.
Operations Manual Diagnostics Diagnostics enables you to run a limited set of diagnostic tests on currently selected groups. The results for each test will indicate either Good or Failed. Choose the System Administration submenu. Enter the letter D for Diagnostics to access the following AT-S13 submenu: The top of the screen shows the user-configured hub name and selected group name. Below is the group’s product identifier.
Ethernet Administration Enter the letter D for Diagnostics to access the following AT-S16 submenu: Connect to a Remote System Select System Administration from the Main Menu. Next, select Connect to a remote system.
Operations Manual For IP Networks. Enter the IP address of the target hub. This option initiates a Telnet session to another ATI managed hub. This option is useful when you are managing remote networks. NOTE If you are specifying the system by its alias, be sure to enclose the name in single quotation marks (for example, ‘name’). When the Telnet connection is established, you will see the remote system’s Main Menu.
Ethernet Administration Frame Statistics When you select Frame statistics from the Main menu, the following screen appears: Options Statistics Counters. Options A through K will display a graph for a particular statistics counter. See Single Counter Graph below. System Overview. This option (L) displays the System Overview Graph Frames (see below). Individual Port Overview. This option (M) displays the Individual Port Menu (see below). Zero all . . . This option (N) clears all statistics counters.
Operations Manual Single Counter Graph If you select one of the individual Statistics Database counters from the Frame statistics submenu (options A through K), the following display (option A, in this case) appears for the AT-S13: If you select one of the individual Statistics Database counters from the Frame statistics submenu (options A through K), the following display appears for the AT-S16: 59
Ethernet Administration The selected statistics counter (Received Frames Filtered, option A, in this example) is graphed on a port-by-port basis. Each port’s counter value is shown to the left of the graph, and the graph itself provides a visual comparison of each port. NOTE This display will be automatically updated if the type of terminal has been configured. The counter will not increase if ANSI is not selected. Rather they will be updated each time you enter the statistics screen.
Operations Manual Individual Port Overview If you select the Individual port overview option (M) from the Frame statistics submenu, the following submenu appears and you are asked to select a desired port: To select a port, you enter the port number, followed by RETURN. A graph similar to the following Individual Port Graph - Frames will then appear.
Ethernet Administration Individual Port Graph — Frames If you select a port number from the Individual Port Statistics, the following display appears. Note that Port #1 was selected. This display is identical to the System Overview Graph except it is for a selected port and not the overall system. Each counter value is shown to the left of the graph and the graph itself provides a visual picture of the port’s network activity.
Operations Manual Error Statistics Menu When you select Error statistics from the Main menu, the following menu appears: Options Statistics Counters. Options A through N will display a graph for a particular statistics counter. See Single Counter Graph above. System Overview. This option (O) displays the System Overview Graph Errors (see below). Individual Port Overview. This option (P) displays the Individual Port Menu (see above). Zero Counters.
Ethernet Administration System Overview If you select the System Overview (option O) from the Error Statistics menu, the following display appears: All of the system-wide statistics counters are graphed. Each counter value is shown to the left of the graph, and the graph itself provides a visual picture of system-wide network activity.
Operations Manual This display is identical to the System Overview Graph - Errors, but reflects only the statistics for the selected port. All of the selected port’s statistics counters are graphed. Each counter value is shown to the left of the graph, and the graph itself provides a visual picture of the port’s network activity.
Ethernet Administration 66
Chapter 4 ATM Administration Getting Started Upgrading a legacy Ethernet network to an Ethernet network with ATM backbone access provides higher throughput as well as the benefits of added bandwidth. On the other hand, it also brings the problem of compatibility. For example, legacy LAN networks and ATM networks have two differences that must be resolved by any protocol which attempts to interface the two technologies: ❑ LAN (MAC) address are defined by the IEEE 802.
ATM Administration An ELAN has two primary functions which are directly relevant to this presentation of ATM Addresses: ❑ It provides a broadcast data path in a connection-based ATM network. ❑ It provides address registration and resolution to the LES and LEC. It also matches MAC addresses to ATM addresses. LANE has been subdivided into the four major components shown below and, as each is discussed in Appendix B, they will not be duplicated here. 1. LAN Emulation Client (LEC) 2.
Operations Manual ATM Parameters Access the Main menu from Omega management. As previously stated, Omega’s Main menu enables you to access the submenus that are needed to configure both your Ethernet network and your ATM network. Select the System Administration submenu by entering the letter S from the Main Menu.
ATM Administration From the System Administration submenu enter the letters AT to access the ATM parameters submenu: This screen enables you to determine the values that regulate your ATM network. The top part of the display shows the current values. The following variables can be configured: UNI 3.0/3.1 signalling. UNI 3.1 represents a slight modification to the earlier UNI 3.0 specification. They vary primarily with differences in the data link Service Specific Convergence Protocol.
Operations Manual ATM addresses As presented in the introduction to this chapter, the function of the ELAN protocol is to emulate (defined as: to imitate, to equal, or to approach equality with) a local area network to an ATM network. Specifically, the ELAN protocol defines the mechanisms that allow the emulation of an IEEE 802.3 Ethernet LAN. In other words, ELAN protocols for Ethernet make an ATM network look and behave like an Ethernet LAN.
ATM Administration MAC Address. Each port has its own MAC address. It does not have an ATM address. The MAC address can be determined as follows: A base MAC address has been assigned to each switch by the manufacturer. [network prefix] [MAC address] [selector byte] If you are unsure of the base MAC address, it can be found either on a decal in the proximate location of the RS232 port and/or on the Omega Diagnostics submenu. An ATM MAC address is created by adding the port number to the base MAC address.
Operations Manual Super LEC “Super LEC” ATM port address is not actually a LEC, nor can it join an ELAN. “Super LEC” is only used to facilitate configuration requests. For example, if a device shows up that has not been heard from before, a configuration request will be sent from your switch to the LECS. This configuration request will, in turn, be acknowledged as valid.
ATM Administration The LAN emulation submenu for the AT-S16 shows no difference. Emulated LAN Definitions This option provides a list of ELAN names associated with each port of your switch. Fields in this menu can only be configured through the LECS. The Emulated LAN Definition option is shown below.
Operations Manual The Emulated LAN Definition menu provides the following information: ❑ ELAN number - There are 64 possible ELAN numbers per switch. Each ELAN number corresponds to the selector byte ❑ ELAN Name - This is the ELAN name associated with the ELAN. The ELAN name is requested and received from the LECS. The ELAN name field may contain up to 32 characters ❑ Status - Normally either Operational or Idle The Emulated LAN Definition option about a particular ELAN is shown below.
ATM Administration Port to ELAN Configuration Submenu — AT-S13/AT-S14 The Port to ELAN Configuration screen displays each UTP port as well as the logically defined management port. By default, all devices on a port are in the same ELAN, but you can override membership assignments for individual devices on a port. A configuration request will be sent to the LECS as new device is attached. A device that receives a positive response from the LECS will join an ELAN.
Operations Manual The Emulated LAN column lists the ELAN that is presently configured to each port. The Type column contains a user defined keyword used by the LECS to configure the port. There are two keywords used by the LECS: ❑ MAC - The LECS assigns an ELAN to a device using the device’s MAC address. When the MAC address is received by the LECS, the MAC address is matched to an ELAN using previously defined information stored in the LECS.
ATM Administration Port to ELAN Configuration Submenu — AT-S16 This screen displays each of the eight (8) actual AT-TS95TR UTP ports as well as the logically defined management port. As the functionality of this screen is essentially identical as that of the AT-4016 screen you are referred that information. Enter po to select the Port to ELAN Configuration submenu. Select a port by typing its number listed on the left of the screen. Port 9 was selected in this example.
Operations Manual MAC Address Table. If you enter an ELAN number from the Port to ELAN Configuration submenu (ELAN #3 in this example) you will see the MAC Address Table option. This option displays all of the MAC addresses discovered by management software on the network. From this screen you can determine all of the MAC addresses that are available, as well as the port or VCI, status, age, ELAN number and name for each MAC address.
ATM Addresses. The LECS uses LEC Media Access Control (MAC) addresses (also known as Ethernet addresses) to determine ELAN assignment. If you do not want to assign a MAC address to each and every device, a default ELAN can be created. For example, the first screen from the Emulated LAN definitions submenu (via the Main and Lan Emulation menus) shows the first sixteen (of 64) ELANs. ELAN Number corresponds to the LEC number.
Operations Manual LECS Configuration From the LAN emulation menu, enter L to select the LECS configuration submenu. The LECS configuration submenu shows the current LECS ATM address. If a connection has NOT been established, there will be no entry. That is, after you have configured your switch, a connection request is sent to the Primary LECS. If the connection request is successful then the Primary LECS ATM Address becomes the Current LECS ATM Address.
ATM Administration Enter P to access the Primary LECS ATM Address submenu. Enter a new ATM address if a current ATM address is not specified or if you simply want to change the existing address. Return to the LECS configuration submenu and enter S to access the Secondary LECS ATM Address screen.
Operations Manual If the secondary LECS ATM address is not found, a search is made for the “Well Known ” LECS Address. This sequence will continue until a connection is made. Since all configuration information originates from the LECS, your switch will not know what ELAN’s are available until the LECS acknowledges that connection. Default ELAN. You can also create a default ELAN on the LECS server with the “Super LEC.
ATM Administration This means that ELANs are established and that a device attached to your LEC will join a configured ELAN. It also means that a configured ELAN will remain joined until either it is reset or it is powered down. Client Status. Client status can be found in the Emulated LAN definitions submenu. Operational means there is traffic for the ELAN across the ATM interface. Idle means that the ELAN configuration is stored in the database but the associated client is not operational.
Operations Manual ELAN Membership The following steps determine which ELAN a device can join during normal network operations. There are FOUR ways to define ELAN membership: 1. When a new device is seen, your switch (LEC) requests configuration information from the LECS. If a MAC address has been preconfigured with the LECS, the LECS will send an acknowledgement message to your LEC and the desired ELAN will be assigned. 2. Your switch (LEC) requests configuration information from the LECS.
ATM Administration ATM Status Menus ATM status and configuration menus are accessible from the Main menu. NOTE The use of the Port, Frame, and Error statistics submenus were discussed in Chapter 3, Ethernet Administration. Since they are not used to actually configure an ELAN, they will not be presented here.
Operations Manual Cell Statistics Menu The Cell Statistics menu enables you to view ATM cell transmit and receive statistics as well as Loss of Frame and Sync events. Fields in this menu cannot be configured. From the Main menu, access the Cell statistics submenu.
ATM Administration Virtual Circuit Information The Virtual Circuit Information (VCI) submenu enables you to view VCI statistics for each active VCI. VCI is the 16-bit number in an ATM cell header which identifies the specific virtual channel on which the cell is traversing on the current physical circuit. From the Main menu, access the Virtual Circuit Information submenu. This submenu will allow you view all active VCIs on the network as well as data information on each.
Operations Manual NOTE VCI number 65 does not have an associated ELAN name but is used as a connection to your LECS. To view additional VCI information in the VCI Statistics Menu, enter an active VCI number and press return. This menu displays statistics for the VCI you specified. Again, Fields in this menu cannot be configured.
ATM Administration NOTE All switch statistics are reset by either selecting the Zero all statistics counters on the entire system option from any statistics menu or by disrupting power to the switch.
Chapter 5 Spanning Tree Protocol Spanning Tree The IEEE 802.1d Spanning Tree Protocol (STP) is both a configuration algorithm and a protocol. When STP is applied to a bridged LAN of arbitrary topology, it will reduce the topology to a single Spanning Tree. This ensures that there is only one data route between two end stations and that there are no data loops.
Spanning Tree Protocol ELAN Spanning Tree Parameters Your switch, along with other Spanning Tree compliant bridges in the network, dynamically configures the network topology into a single Spanning Tree by exchanging Bridge Protocol Data Units (BPDUs). Typically, each LAN segment is sent one BPDU every two seconds. When there are multiple ports connecting LANs in a loop, the Spanning Tree algorithm determines which port should forward packets to the LAN.
Operations Manual A port enters the blocking state because it has received information that another bridge is the designated bridge for the LAN to which the port is attached. ❑ ❑ ❑ ❑ Blocking indicates a port that is NOT PARTICIPATING in forwarding frames thusly preventing the creation of multiple topology paths. Received frames are discarded and frames are not submitted for transmission. Station locations are not added to the database.
Spanning Tree Protocol If, for example, you select ELAN 1, the following screen appears: Bridge Priority When you select “Bridge Priority”, the following screen appears: Bridge priority is used by the Spanning Tree algorithm to determine the root bridge. It consists of a two-byte bridge priority concatenated with a 6-byte MAC address.
Operations Manual You can set the bridge priority by entering a decimal number from 0 to 65,535. Zero being the highest priority. Max Age Time When you select “Max age time,” the following screen appears: The maximum age time is the received bridge protocol information before it is discarded, in seconds.
Spanning Tree Protocol Hello Time When you select “Hello time,” the following screen appears: Hello Time is the amount of time between the transmission of configuration BPDUs on any port when it is the root of the spanning tree (or trying to become so). This value is always zero on the root bridge.
Operations Manual Forwarding Delay When you select “Forwarding delay,” the following screen appears: Forwarding delay is the amount of time that controls how fast a port stays in each of the Listening and Learning states. This value is also used to age out all dynamic entries in the database when a topology change has been detected and is underway.
Spanning Tree Protocol ATM Port - Enable/ Disable/Priority ATM Port Enable/Disable either enables or disables the Spanning Tree for the ATM port. When you select “ATM Port - Priority,” the following screen appears: You can set the port priority by entering a decimal number from 0 to 255. Zero is the highest priority.
Operations Manual ATM Port Cost is the cost of the path to the root as seen from the port. This 2-Byte port cost is concatenated with a 6-byte MAC address and can be specified by entering a decimal number between 0 and 65,535. Port To Spanning Tree ELAN Configuration Returning to the Bridging menu, select “Port to spanning tree Elan configuration.
Spanning Tree Protocol If you select a particular port (Port #1 in this instance), the following screen appears: This menu allows you to either enable or disable the Spanning Tree Protocol for the port. It also allows you to view the ELAN identification (name) as well as the priority and cost for that ELAN.
Chapter 6 Software To Obtain New or Upgraded Software There are several ways to obtain new or upgraded software: ❑ PCMCIA — through Allied Telesyn’s optional AT-S13/AT-S14 PCMCIA card ❑ EPROM Cassette — through Allied Telesyn’s optional AT-S16 Firmware Cassette ❑ FTP Server ❑ TFTP — using Allied Telesyn’s Omega Manager which is an on-line TCP/IP family TFTP file transfer procedure ❑ 24-hour On-line BBS ❑ Internet ❑ CompuServe The procedures and telephone numbers for ATI’s BBS, Internet and C
Software PCMCIA Allied Telesyn offers Omega management software for the AT-4016TR and the AT-4016F on a firmware PCMCIA card, the AT-S13 and the AT-S14 respectively. AT-S 13 AT-S7 Figure 6: AT-S13 PCMCIA Card PCMCIA Port. The PCMCIA card is a read-only interface used for restoring or updating software. If a PCMCIA card is installed before a reset or power-up sequence, the switch boots from the PCMCIA card. Otherwise, it boots from internal Flash RAM. To update software through the PCMCIA port: 1.
Operations Manual Firmware Cassette Firmware Cassette Port Figure 7: AT-S16 Firmware Cassette Port Firmware Cassette Port. AT-TS95TR agent software is easy to upgrade through the Firmware Cassette port (see Figure 7). The Firmware Cassette is a read-only interface used for restoring or updating software. If a Firmware Cassette is installed before a reset or power-up sequence, the AT-TS95TR boots from the Firmware Cassette. Otherwise, it boots from internal Flash RAM.
Software FTP Server Allied Telesyn has Internet access to an FTP Server for driver and Readme files on our adapter cards and managed products. The server can be accessed through your Internet connection as follows (note — use lower case letters): Address gateway.centre.com [lowercase letters] Login anonymous [lowercase letters] Password your e-mail address [requested by the server when you login] The first thing you should do once you access the server is to read the CONTENTS.TXT file.
Appendix A TFTP Background Software can be downloaded using the Trivial File Transfer Protocol (TFTP) and ATI’s image file. ATI’s switches support the use of TFTP in ASCII mode to both upload configuration parameters to a host and/or download configuration parameters to a switch. What this means is straightforward: you can save configuration data from many switches to a single host.
TFTP TFTP Configuration Data Requirements The following information lists the configuration field and the required character string that precedes the user configuration value that has been chosen. Each configuration field data text string entry must be separated from the previous and the following by new line character sequence, i.e., carriage return (0x0D hex) or carriage return/linefeed (0x0D 0x0A hex) character combination. Without this delineation, the configuration of the fields will not occur.
Operations Manual NOTE Not all configuration fields apply to all products. This file includes configuration data for the AT-S6 (AT-3690), AT-S7 (AT-4016 with PVC’s), AT-S9 (AT-TS95TR) with PVC’s and AT-S13/AT-S14 (AT-4016TR and AT-4016F with SVC’s) and the AT-S16 (AT-TS95TR with SVC’s). Exceptions are noted. Get To obtain a current image for an AT-4016TR, AT-4016F, or AT-TS95TR respectively, enter either: tftp get image.s13 (MAC address) AT4016 octet (or) tftp get image.
TFTP When you use TFTP, the file name for the switch must be the same as the downloaded password. For example, if you had changed the default download password to ALLIED, and the configuration file on your PC was NEWCONF, your TFTP command line might look like the following: TFTP PUT NEWCONF 135.24.35.
Operations Manual Terminal Clear Line Control Character Sequence: CLR LINE SEQ = “XXXXXXXXXXXXXXXXXXXX” Allowable configuration data: A maximum of twenty (20) ASCII characters Default Value: NULL STRING IP Address: IP ADDR = XXX.XXX.XXX.XXX Allowable configuration data: Four numeric values separated by (.) ranging from 0 - 255. Default Value: 00.00.00.00 Subnet Mask: SUBNET MASK = XXX.XXX.XXX.XXX Allowable configuration data: Four numeric values separated by (.) ranging from 0 - 255.
TFTP SNMP Trap String: TRAP STRING = “XXXXXXXXXXXXXXXXXXXX” Allowable configuration data: A maximum of twenty (20) ASCII characters Default Value: “public” System Location: SYS LOCATION = “XXXXXXXX.........XXXXXXXX” Allowable configuration data: A maximum of sixty-four (64) ASCII characters Default Value: NULL STRING System Contact: SYS CONTACT = “XXXXXXXX.........
Operations Manual PORT NAME = 16 “XXXXXXXX.........XXXXXXXX” Allowable configuration data: A maximum of twenty (20) ASCII character name NOT INCLUDING the port number Default Value: NULL STRING System Configuration Reset: Allowable configuration data: RESET TO SYSTEM DEFAULTS NONE. When this field identifier is received, the systems configuration data will be set to its default value. ATM Configuration Description FIELD IDENTIFIER and VALUEs System ATM Address: SYSTEM ATM ADDRESS = “XXXXXXXX......
TFTP System ATM UNI Signaling ATM SIGNALING = UNI Allowable configuration data: 3.0, 3.1 Default Value: UNI 3.
Operations Manual Bridge Age Time: ST AGE_TIME [1] = 20 ([Bridge number] = value) ST AGE_TIME [2] = 20 : : ST AGE TIME [64] = 20 Allowable configuration data: A numeric value ranging from 6 - 40 Default Value: 20 Bridge Hello Time: ST HELLO TIME [1] = 2 ([Bridge number] = value) ST HELLO TIME [2] = 2 : : ST HELLO TIME [64] = 2 Allowable configuration data: A numeric value ranging from 0 - 10 Default Value: Bridge Forwarding Delay: 2 ST FWD DELAY [1] = 15 ([Bridge number] = value) ST FWD DELAY [2
TFTP ATM Port Priority: ST ATM PORT-PRIORITY [1] = 128 ([Bridge number] = value) ST TM PORT-PRIORITY [2] = 128 : : ST ATM PORT-PRIORITY [64] = 128 Allowable configuration data: A numeric value ranging from 0 - 255 Default Value: 128 ATM Port Cost: ST ATM PORT COST [1] = 6 ([Bridge number] = value) ST ATM PORT COST [2] = 6 : : ST ATM PORT COST [64] = 6 Allowable configuration data: A numeric value ranging from 0 - 65535 Default Value: 6 Spanning Tree Port to Elan: ST PORT ELAN [1] = 1 ([Port nu
Operations Manual Default Value: Spanning Tree Port Priority: 100 ST PORT PRIORITY [1] = 255 ([Port number] = Value) ST PORT PRIORITY [2] = 255 : : ST PORT PRIORITY [16] = 255 Allowable configuration data: A numeric value ranging from 0 - 255 Default Value: 128 Spanning Tree Port Enabled: ST PORT ENABLED [1] = DISABLED ([Port number] = Value) ST PORT ENABLED [2] = DISABLED : : ST PORT ENABLED [16] = DISABLED Allowable configuration data: DISABLED, ENABLED Default Value: DISABLED ELAN/VLAN Def
TFTP Port to ELAN Configuration: PORT ELAN ID [1] = 1 ([Port number] = Elan number) PORT ELAN ID [2] = 2 : : PORT ELAN ID [16] = 1 Allowable configuration data: A port number 1 - 16 followed by an ELAN/VLAN number 1 - 64 Default Value: Elan 1 Exceptions: For AT-S6 and PVC systems only (AT-S7, AT-S9) Port to ELAN Configuration Type: PORT ELAN TYPE [1] = MAC ([VLAN number] = Config Type) PORT ELAN TYPE [2] = MAC : : PORT ELAN TYPE [64] = MAC Allowable configuration data: MAC, FIXED Default Value:
Operations Manual Allowable configuration data: A number from 1 - 1023 Default Value: 0 Exceptions: For PVC systems only PVC ATM Address: PVC ATM ADDRESS [1] = “XX........XXX” ([PVC Number] = Value) PVC ATM ADDRESS [2] = “XX........XXX” : : PVC ATM ADDRESS [128] = “XX........
TFTP 110
Appendix B LAN Emulation ATI’s ATM software implements ATM Forum’s Lan Emulation Client (LEC). LEC implementation, in turn, conforms to the Lan Emulation Specification 1.0. That is, your switch implements LEC functionality between a legacy Ethernet device and an ATM network. This is important since connection to the LAN Emulation Service (LES) is through LECs.
LAN Emulation That is, when a LEC is presented with a frame for transmission whose LAN destination is unknown to that client, it must issue a LAN emulation address resolution protocol request frame to the LES over its control point-to-point VCC. The ATM protocol requires a destination ATM address to set up a connection across the network. Yet most people will only “know” the MAC address of the destination.
Operations Manual LANE LANE allows you to create multiple different ELANs within the network. The following diagram shows how one LAN host communicates to another LAN Host. LANE allows existing LANs to use ATM as a transit path between similar LAN types. ATM then becomes a backbone path which, in turn, allows ATM workstations to communicate with attached LANE stations.
LAN Emulation The following diagram shows how an Ethernet host communicates to an ATM host using LANE. MAC Layer Note that, in switched virtual connection (SVC) environments, LANE entities (e.g., LEC, LES and BUS) set up connections between each other using UNI signaling and a best effort quality of service. Components of LANE LANE has been subdivided into four major components, each of which will be discussed: 1. LAN Emulation Client (LEC) 2.
Operations Manual LAN Emulation Client (LEC) LEC performs address resolution, data forwarding and other control functions. It does this by providing a MAC level emulated 802.3 or 802.5 interface to higher level software such as bridging functions. LEC implements the LANE User-Network Interface (LUNI) with other entities within the Emulated LAN.
LAN Emulation Lan Emulation Services The LES, BUS and LECS are collectively referred to as LAN Emulation Services. LAN Emulation Server (LES). Each LES provides Address Resolution Request (ARP) services for one ELAN. When a client joins an ELAN, the client broadcasts a 48-byte MAC address to the LES. The LES maps the MAC address to a 20-byte OSI NSAP address to create an ATM address. The new ATM address is then returned to the client.
Operations Manual A BUS is the multicast server for an ELAN. It handles all broadcast, multicast and unknown unicast traffic. Packets to be broadcast from the LEC are sent to the BUS. The BUS then sends the packets back to all the LECs using the point-to-multipoint connection. LECs also send packets with unknown destinations to the BUS. The BUS forwards these packets to every LEC on the ELAN, including the source LEC where the packet originated.
LAN Emulation SNMP is defined by RFC-1157 and published by the Internet Engineering Task Force. Full details of the ATM UNI MIB and of generic SNMP are beyond the scope of this publication. The essential parameters are, however, as follows: ❑ Physical layer type (SONET), medium (UTP, fiber, coaxial cable and more), unique index number, status (normal or looped) and relevant specifications. ❑ Number of ATM virtual paths and connections allowed. Numbers active.
Operations Manual If the LES does not have the ATM address of the MAC address, it will run an address resolution protocol to resolve it. After receiving a reply with the ATM address from the LES, the LEC sets up a point-to-point VCC to that destination ATM address. After the data VCC is set up, all subsequent data will be sent over the VCC to the LAN destination. LEC ↔ BUS. After obtaining the BUS’s ATM address from the LES, a VCC LEC sets up a bi-directional Multicast Send VCC to the BUS.
LAN Emulation 120
Appendix C MIBs Management Information Base (MIB) documents are defined by the IEEE in “Requests For Comments” (RFCs). The core of the industry-standard SNMP MIB, MIB II (RFC 1213), contains general variables relating to IP, TCP, and UDP statistics for network devices such as repeaters, routers, and gateways. The MIB II client is implemented as part of Omega. Each MIB variable (managed object) has a value, either numeric or string (text). These values are stored in registers or accumulators in the switch.
MIBs ❑ RFC 1695—ATM MIB ❑ ATM Forum—UNI (User-to-Network Interface) MIB ❑ ATM Forum—Interim Layer Management Interface (ILMI MIB) ❑ ATM Forum 94-0737R2—LAN Emulation Client Many parameters are described by existing MIB documents. The meanings of those parameters are not always implemented exactly; instead, the parameters are treated as best as can be correlated.
Operations Manual MIB Types The MIB definitions in this document may reference the primitive types that are described in the Structure and Identification of Management Information for TCP/IP-based Internets, RFC 1155. RFC 1155 is based on the Specification of Abstract Syntax Notation One, ASN.1. The primitive types are described in the following Table. Primitive Size Description Boolean 1 byte Enumerated Integer with possible true (1) or false (2) values; note that the ASN.
MIBs 3. Obtain the current value of certain parameters and simultaneously change the value of other parameters - the NMS uses the SetRequest PDU, and the switch responds with a GetResponse PDU. For the parameters which are being obtained rather than changed, the NMS must use the ASN.1 NULL value with the SetRequest PDU. 4. Provide notification of significant events - the switch uses the Trap PDU and/or the Get Response PDU.
Operations Manual IP Address Translation Table The TCP/IP IP address translation table contains mappings of Internet addresses to MAC addresses, except for the Internet addresses itself. The parameters are Read/Write, according to TCP/IP MIB-II; however, the switch has the restriction that a dynamic entry should not be modified, except to be made “invalid” (any other modifications will cause a static entry to be created).
MIBs snmpInBadCommunityUses{snmp 5} Counter Read-Only The number of SNMP PDUs received by the AT-4016TR which had an authentication failure. snmpInASNParseErrs {snmp 6} Counter Read-Only The number of SNMP PDUs received by the AT-4016TR which had an ASN.1 parsing error while being decoded by the AT-4016TR. snmpInBadTypes {snmp 7} Counter Read-Only All GetResponse PDUs indicate a noSuchName ErrorStatus, since this variable is no longer used.
Operations Manual snmpInSetRequests {snmp 17} Counter Read-Only The total number of SNMP SetRequest PDUs received by the AT-4016TR, which have been processed with no errors. snmpInGetResponses {snmp 18} Counter Read-Only Always zero, since the AT-4016TR ignores all SNMP response PDUs. snmpInTraps {snmp 19} Counter Read-Only Always zero, since the AT-4016TR ignores all SNMP Trap PDUs.
MIBs snmpOutTraps {snmp 29} Counter Read-Only The total number of SNMP Trap PDUs created by the AT-4016TR. snmpEnableAuthenTraps {snmp 30} Integer Read-Write Whether authentication failures should cause the AT-4016TR to generate authentication-failure Trap PDUs. Values include: enabled (1) generate traps disabled (2) do not generate traps Ethernet MIB Your switch supports the Ethernet MIB as defined in Definitions of Managed Objects for the Ethernet-like Interface Types, RFC 1284 (J.
Operations Manual linkDown (2) A port has failed, and the local management agent has disabled usage of the port. The “variable-bindings” portion of the trap contains the ifIndex of the port. linkUp (3) A port has come back to life, and the local management agent has re-enabled usage of the port. The “variable-bindings” portion of the trap contains the ifIndex of the port.
Appendix D Glossary 10BASE-T—IEEE 802.3 UTP Ethernet. Low-cost Level 3 or better UTP wiring affords 100 meters (328 ft.) of point-to-point link segments. UTP uses RJ45 connectors and sometimes 50-pin AMP connectors to a patch panel and runs at 10 MHz. ADDRESS RESOLUTION PROTOCOL (ARP)—The procedures and messages in any communications protocol which resolve local addresses to those of the network. In TCP/IP, the protocols for translating between IP addresses and physical addresses.
Glossary there would be two transmitters on one pair and no receiver. As a solution, the crossover cable crosses the TD pair with the RD pair, to connect the TD pins on one end to the RD pins at the other end. CYCLIC REDUNDANCY CODE (CRC)—An algorithm used to check for and correct bit errors in data transmission. DATA COMMUNICATION EQUIPMENT (DCE)—In RS232 specification a module, such as a modem, for connecting a DTE to other equipment.
Operations Manual LAN EMULATION CLIENT (LEC)—ATM Forum-defined specifications in support of LAN-to-LAN connectivity, called LAN Emulation. LEC defines that set of functions implemented in a LAN DTE to interface with an ATM network in support of LAN Emulation. LAN EMULATION SERVER (LES)—LES defines that set of functions implemented in an ATM network in support of LAN-to-LAN connection establishment.
Glossary NETWORK SERVICES ACCESS POINT (NSAP)—OSI generic standard for a network address consisting of 20 octets. ATM has specified E.164 for public network addressing and the NSAP address structure for private network addresses. PATCH PANEL—A 10BASE-T patch panel may be used between a punch-down block and UTP workstation. The patch panel generally has a female RJ45 connector on the front for each workstation and a Telco (RJ21) connector on the back, which is wired to a punch-down block.
Operations Manual STANDALONE—Repeater operating as a hub on its own; i.e., not a module among other modules in a department concentrator chassis. STRAIGHT-THROUGH—A type of wiring connection where the pins of one connector connect to the same pins of another connector. For example, pin 1 of one connector connects to pin 1 of another connector. STRAIGHT TIP (ST) CONNECTOR—A type of port connection where the pins connect through a bayonet-style interface.
Glossary USER-TO-NETWORK INTERFACE (UNI)—The interface between an end device and a public or private ATM switch. VIRTUAL CIRCUIT (VC)—A connection between end users that has defined end points and route but does not have bandwidth dedicated to it. Bandwidth is allocated on demand by the network as users have traffic to transmit. VIRTUAL CHANNEL CONNECTION (VCC)—Virtual channels in two or more sequential physical circuits can be concatenated to create an end-to-end connection called a VCC.
Appendix E Technical Support Fax Order Name ___________________________________________________________________ Company ________________________________________________________________ Address _________________________________________________________________ City ____________________State/Province____________ Zip/PostalCode __________ Country _______________________ Phone______________________ Fax _________ Incident Summary Model number of Allied Telesyn product I am using _____________________________ F
Appendix F Where To Find Us For Technical Support or Service Location Phone Fax North America United States, Canada, Mexico, Central America, South America, Australia, New Zealand 1 (800) 428-4835 1 (206) 481-3790 France France, Belgium, Luxembourg, The Netherlands, Middle East, Africa (+33) 1-69-28-16-17 (+33) 1-69-28-37-49 Germany Germany, Switzerland, Austria, Eastern Europe (+01) 30-83-56-66 (+49) 30-435-70-650 Italy Italy, Spain, Portugal, Greece, Turkey, Israel (+39) 2-38093-444 (+39) 2
Appendix G Index A activity monitor 15 address Sunnyvale 139 world wide web 139 address registration 6 administration 50, 51, 53 ANSI 50, 63 Asynchronous Transfer Mode (ATM) 131 ATM cell header 72 auto configuration 10 B Backplane 44 backplane if slot occupied 47 BBS x, 96 bit rate 131 bit time 131 BootP server 16, 40 Bridge Address Table 8 Bridge priority 86 Bridge Protocol Data Units (BPDUs) 84 Bulletin board service ix C cabling 10BASE2 131 10BASE-T 42, 131 crossover 131 FOIRL 132 impedance 132 straigh
Index individual port statistics 64 options 61 statistics counters 61 zero counters 61 front panel if link onling interface autosense 47 full duplex 50 G glossary 131 H half duplex 50 Hello time 88 hot swapping 132 hub/repeater 132 I IEEE 802.
Operations Manual Provisioned Virtual Circuits (PVC’s) 6 punch-down block 134 PVC 134 R repeater 134 request for comments (RFC) 121 RS232 54 RS232 console port 10 RS232 serial port 39, 40 S sales information 139 SDH 134 SDH-1 21 Secondary LECS 23, 79 segmented backplane 47 selector byte 25 serial port 10 Signal Quality Error 134 Simple Network Management Protocol 134 single mode fiber 134 SNMP 134 software level 58 SONET 21, 134, 135 Spanning Tree Protocol (STP 83 Spanning Tree Protocol (STP) 8 SQE 134 Sto
