 






     Software
     Product
     Description

     ________________________________________________________________

     PRODUCT NAME:   MUXserver 300 Remote Terminal Server for VMS,
     SPD 25.E9.02
                     Version 1.2

     DESCRIPTION

     The MUXserver 300 Remote Terminal Server is a wide area terminal
     switch for Ethernet Local Area Networks. It has been designed
     to support interactive asynchronous terminal users, using data
     compression, background priority, and statistical multiplexing
     to optimize the network performance.

     In general, the MUXserver/DECmux 300 provides the same terminal
     services to a remote workgroup as the DECserver products give to
     local users.

     The term "MUXserver/DECmux 300" used throughout this document
     refers to a network built from MUXserver 300/310 and DECmux
     308/316/332.

     A MUXserver/DECmux 300 network provides a convenient method to
     connect workgroups of remotely located asynchronous terminals,
     printers, and computers to each other and to one or more service
     nodes (hosts) on an Ethernet.

     MUXserver/DECmux 300 main features:

     o  LAT protocol

     o  192 devices

     o  96 concurrent sessions

     o  64 concurrent users (MUXserver 300)

     o  16 concurrent users (MUXserver 310)

                                  DIGITAL               November 1990

                                                          AE-MG98C-TE

 


     MUXserver 300 Remote Terminal Server for VMS,       SPD 25.E9.02
     Version 1.2


     o  link speed 2400 bps to 64K bps

     o  Data Compression

     o  Background priority

     o  Statistical Multiplexing

     o  Optimized for remote echo terminals

     o  Host load balancing

     o  Multiple sessions

     o  Printer support

     o  Pass through

     o  Security

     o  On-line help

     o  Queuing

     Features

     Terminal Connection Management

     Through the use of a simple command, users can establish a
     logical connection, called a session, to any service node that
     implements the LAT protocol on the same Ethernet LAN. This
     connection makes the terminal appear as if it were physically
     connected to the service node, and the terminal user can use
     standard system utilities and applications supported by that
     node. Each terminal connected to the DECmux 300 remote terminal
     multiplexer can connect to the same or a different service node
     on the Ethernet.

     A service node can have one or more services that are offered
     to MUXserver/DECmux 300 network users. Services and nodes are
     identified by name. Users always connect to services, not to
     nodes, although often one of the service names will be the node
     name.

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     MUXserver 300 Remote Terminal Server for VMS,       SPD 25.E9.02
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     In a VAXcluster environment, the MUXserver/DECmux 300 sees each
     VAXcluster on the Ethernet as a collection of service nodes
     offering a common service. Each cluster node may also offer a
     service whose name is equivalent to its node name. In this case,
     a terminal user can connect either to the cluster service or a
     service associated with a particular cluster node.

     Non-LAT Host Support

     The MUXserver/DECmux 300 can be used to provide logical terminal
     connections to hosts that do not implement the LAT protocol.
     In this type of configuration, the server becomes the Ethernet
     connection and protocol support for these hosts. This expands
     the LAT network accessibility to include LAT hosts directly
     connected to the same Ethernet and hosts connected to the LAT
     network by means of the MUXserver/DECmux 300 network, and non-
     LAT hosts connected to the same Ethernet by means of a DECserver
     terminal server.

     A host that supports XON/XOFF, ASCII standards, and EIA
     232-D/CCITT V.24/V.28 interfaces can be connected to the
     MUXserver/DECmux 300. This provides the terminal user with a
     transparent connection to the non-LAT host. It is strongly rec-
     ommended that the server port and the host side port use modem
     control signals to signal the host automatically on session
     disconnection.

     In this configuration, there is a one-to-one correspondence
     between the port on a MUXserver/DECmux 300 and the connection on
     the host. The server manager assigns service names to individual
     ports or groups of ports that connect the host interface to the
     server.

     Load Balancing

     When a connection is made to a service, the actual node for
     the connection is determined by load balancing. Load balancing
     is the process the server uses when more than one node offers
     the same service. Service nodes do not have to be configured
     in a cluster in order for load balancing to be used. Service

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     MUXserver 300 Remote Terminal Server for VMS,       SPD 25.E9.02
     Version 1.2


     nodes with the same names may be running different operating
     systems. Using the load balancing process, the server connects
     to the node with the highest rating for the service desired.
     This rating is based on the current loading on the nodes that
     offer the service.

     Multiple Sessions

     The MUXserver/DECmux 300 allows each user to establish and
     maintain up to eight sessions to one or more service nodes,
     up to a maximum of 96 per MUXserver/DECmux 300 network. Only
     one session per user can be active at a time. Through simple
     switching commands, the user can access the different sessions
     without repeating a login dialog each time. Some operating
     systems may impose limits on the number of LAT sessions such
     a host will support.

     Multiple Session Management

     The MUXserver/DECmux 300 server allows direct communication
     with devices that support the Terminal Device/Session Management
     Protocol (TD/SMP) protocol. This protocol provides the ability
     for the attached device to maintain screen and keyboard context
     for multiple LAT sessions.

     Outbound Connection Queues

     If a terminal user requests a connection to a service, and the
     requested service is currently in use, the terminal server
     users may opt to have the connection requested queued to the
     remote service. This feature will happen automatically whenever
     a connection fails for this reason if the user's port has been
     appropriately configured, and the service node is queuable.
     The connection request is queued at the service node end and is
     processed first-in/first-out until the user's connection request
     can be completed. This feature assists in the fair management of
     limited network resources. Once queued for connection, the user
     also has the option to cancel the queue entry and proceed with
     other sessions.

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     MUXserver 300 Remote Terminal Server for VMS,       SPD 25.E9.02
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     Inbound Connection Queues

     The MUXserver/DECmux 300 may offer ports as services. If a
     request is received for a connection to a service and that
     service is being used, the MUXserver 300 may offer a queuing
     facility for incoming connect requests. Connect requests are
     granted on a first-come first-served basis.

     Access Contention

     A fully configured MUXserver/DECmux 300 network can provide
     physical connections for 192 terminals. The MUXserver 300 will
     provide access to the first 64 users on a first-come first-
     served basis. The MUXserver 310 will provide access to the
     first 16 users. Permanent logical connections may be assigned
     to specific ports to ensure access at all times. When a logical
     connection is not available, a status message is relayed to the
     port requiring access.

     Welcome Identification

     The MUXserver/DECmux 300 server standard welcome banner, which
     includes terminal server type, version number, internal base-
     level, and protocol version number, is issued whenever a user
     successfully logs in to the server. The server will also print
     a server manager settable identification string. This can be
     useful for automatic server identification, or for small daily
     messages used for communication with the terminal server users.

     Local Mode and Service Mode

     For the most part, the environment provided by the MUXserver/DECmux
     300 is identical to the environment the user would experience if
     attached directly to the service node. When operating in this
     mode, the user is said to be in Service Mode. Occasionally, such
     as during connection establishment, the user interacts directly
     with the MUXserver/DECmux 300. When operating in this mode, the
     user is in Local Mode.

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     MUXserver 300 Remote Terminal Server for VMS,       SPD 25.E9.02
     Version 1.2


     In Local Mode, the terminal input is interpreted directly by
     MUXserver/DECmux 300 as commands to be performed by the server.

     In Service Mode, the terminal input is passed directly to the
     connected service node with several exceptions. One exception,
     called the local switch character, allows the user to enter Lo-
     cal Mode from Service Mode. The <BREAK> key may also be used for
     this function. Other exceptions, called the forward and backward
     switch characters, allow the user to switch between sessions
     without the need to enter Local Mode. The switch characters are
     disabled by default but may be enabled by command. Both CTRL/S
     and CTRL/Q are normally interpreted locally, but flow control
     using these characters can be disabled.

     Autoconnection

     Autoconnection is a function that automatically connects a user
     terminal to a service node when connection failures occur or on
     user login to the server. In conjunction with this function,
     a dedicated or preferred service can be specified for each
     terminal user.

     If a dedicated service is specified, the MUXserver/DECmux 300
     will attempt to connect to that service when a character is
     typed on the terminal keyboard or when an existing connection
     fails. In dedicated service mode, only one session is available.
     As this mode is designed to simulate a direct terminal connec-
     tion, no local mode commands or messages are available to the
     terminal user. Ports with dedicated service can be automatically
     logged out of the server when the user logs out of the service
     node.

     If a preferred service is specified, the MUXserver/DECmux 300
     will attempt to connect to that service as with the dedicated
     service mode of operation. However, the terminal user can enter
     local mode and establish other sessions.

     Automatic Session Failover

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     MUXserver 300 Remote Terminal Server for VMS,       SPD 25.E9.02
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     If a service is available on two or more service nodes and a
     connection to a service fails, the server will attempt to con-
     nect the user to another service node offering the same service.
     The user's context at the time of failure is not automatically
     restored and login to the new service is required.

     Groups

     Every terminal and service node in a LAT network is a member
     of one or more groups, which are specified by a list of numbers
     from 0 - 255. Groups allow an easy means of subdividing the net-
     work into what appears to be many smaller networks. A terminal
     user is only aware of the services that are offered by nodes in
     the same group(s).

     The server manager can specify the authorized group(s) in which
     a terminal is a member. The authorized groups define the set of
     services that the user is allowed to access. In addition, a user
     can further restrict access to services by disabling some of
     the authorized groups using a non-privileged group command. The
     user-settable group codes are a subset of the authorized groups.

     Groups provide a restrictive view of the network. This re-
     stricted view is mainly for user convenience, and although it
     also provides a form of security, it is not intended to be the
     primary form of access authorization or system security for a
     node.

     Security

     The MUXserver/DECmux 300 provides functions that enhance se-
     curity features already available in the service nodes. These
     functions may be enabled as required by the server manager.

     o  Port login password.

     o  Port lock password. This allows the user to leave sessions
        running at the terminal without fear of security violations.
        When a terminal is locked, all input from the terminal is
        ignored until the lock password is re-entered.

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     MUXserver 300 Remote Terminal Server for VMS,       SPD 25.E9.02
     Version 1.2


     o  Secure Port allows a user to change only dynamic settings on
        that port.

     o  Non-privileged User can change dynamic and permanent settings
        on that port.

     o  Privileged User can change all settings. This mode is pass-
        word protected.

     On-line HELP Facility

     A full on-line reference HELP facility is available. The
     server's HELP command provides information on the correct syn-
     tax and details about each command. In addition, a tutorial
     HELP feature allows new users to learn quickly the basics of
     MUXserver/DECmux 300 operation. Tutorial HELP can be entered
     when logging in to the server.

     Directory Service

     Any MUXserver/DECmux 300 user can obtain a directory of services
     available to that user with a SHOW SERVICES command. Services
     for which the user's port is not authorized will not be dis-
     played.

     Permanent Characteristics

     The MUXserver/DECmux 300 maintains permanent characteristics
     in non-volatile memory that is retained even when the power
     is disconnected. Permanent characteristics are maintained for
     service and server parameters as well as per-port parameters.
     Permanent characteristics can be reset to factory defaults by
     pressing the software reset button on the hardware unit while
     plugging in the power cord.

     Port Characteristics Configuration

     Characteristics governing the operation of an individual port
     can be displayed by a non-privileged terminal user interactively
     from that user's terminal. Many of the characteristics may be

                                     8

 


     MUXserver 300 Remote Terminal Server for VMS,       SPD 25.E9.02
     Version 1.2


     set up by the user, but certain characteristics are privileged
     and can only be changed by the Server Manager.

     Port parameters that can be set and displayed include: speed,
     character size, group codes, parity, terminal type, access,
     autobaud, modem, and password protection.

     Port Access

     A port on a MUXserver/DECmux 300 can be set up in different ways
     depending on the device attached to the port and its intended
     use. MUXserver/DECmux 300 supports EIA 232-D and DECconnect
     asynchronous devices operating at speeds up to 19.2K bps.

     Port access is the characteristic that determines how a port may
     access or be accessed by interactive users and service nodes.

     o  Access Local - Designed for interactive terminals. This al-
        lows the device (typically an interactive terminal) attached
        to the port to CONNECT to LAT services. This type of access
        is also used for dial-in modems.

     o  Access Remote - Designed for applications-driven devices
        (like asynchronous printers) that are allocated by a service
        node process. This allows the implementation of certain
        shared printers by multiple service nodes. This type of
        access is also used for connections to dial-out modems and
        non-LAT host systems.

     o  Access Dynamic - Designed for devices (like personal comput-
        ers or printers with keyboards) that require both Local and
        Remote access.

     o  Access None - Designed to allow the server manager to disable
        the use of a port.

     Data Compression


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     MUXserver 300 Remote Terminal Server for VMS,       SPD 25.E9.02
     Version 1.2


     Data Compression is automatically enabled and disabled on a
     per-port basis. It is dependent on the type of data being trans-
     mitted and is effective only on blocks of data. Therefore,
     compression efficiency will vary with the application.

     Background Priority

     Background priority is enabled on a per-port basis. Traffic to
     and from ports set to background is reduced in favor of other
     traffic. This feature is especially useful for ports that are
     used for printers.

     Terminal Operation

     The MUXserver/DECmux 300 software supports the simultaneous
     operation of asynchronous devices at speeds from 75 bps to 19.2K
     bps. The total aggregate throughput is dependent on network link
     speeds and will typically be less than the sum of the individual
     terminal connections. The software also supports:

     o  Full modem control support (on DECmux 300 EIA 232-D ports
        only)

     o  Data leads only support (on DECmux 300 EIA 232-D and DEC423
        ports)

     o  XON/XOFF flow control

     o  CTS/RTS or DSR/DTR flow control (on DECmux 300 EIA 232-D
        ports only)

     o  Split speed (transmit and receive) terminal operation

     o  Modem fallback features (on DECmux 300 EIA 232-D ports only)

     o  Block Mode transfers

     o  Automatic line speed detection (equal receive and transmit
        speed only)

     o  Digital personal computer file transfer

     o  Data transparency mode

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     MUXserver 300 Remote Terminal Server for VMS,       SPD 25.E9.02
     Version 1.2


     o  Ability to pass break character and error notification

     o  Ability to assist in multiple session management by means of
        TD/SMP

     Network Configuration

     The MUXserver/DECmux 300 network is built from two basic op-
     tions, the MUXserver 300/310, which connects to the Ethernet,
     and the remote unit, the DECmux 308/316/332.

     MUXserver 300/310

     Each MUXserver 300/310 can support up to two synchronous commu-
     nications lines, and each line can support up to three DECmux
     300s, thus supporting a maximum of six DECmux 300s.

     The MUXserver 300/310 is connected to an Ethernet using a DELNI,
     DECOM, DESTA, H4000, or H4005, by means of a transceiver cable.
     The MUXserver 300/310 Ethernet port is compatible with Ethernet
     V2 and IEEE 802.3 Local Area Networks.

     The MUXserver/DECmux 300 composite links use HDLC LAPB data link
     protocols and can be connected using the following physical link
     options. Network configuration, link types, and link speeds are
     automatically configured when the correct cables are used.

     o  EIA 232-D/CCITT V.28 at 2.4K to 19.2K bits per second

     o  CCITT X.21 bis /CCITT V.35 at 48K to 64K bits per second

     o  EIA RS-449/CCITT V.36 up to 64K bits per second

     o  CCITT X.21, leased-line only, up to 64K bits per second

     o  EIA RS-422 up to 64K bits per second

     The MUXserver/DECmux 300 EIA RS-422 composite link can be used
     to connect two units together. Clocking signals are supplied by
     the MUXserver. Distances up to 1200 meters, or 4000 feet, are
     supported on suitable cable installations.

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     MUXserver 300 Remote Terminal Server for VMS,       SPD 25.E9.02
     Version 1.2


     The MUXserver/DECmux 300 network is designed to operate over
     wide area network links that provide no significant delay and
     a transparent data path. Synchronous composite links oper-
     ating over multiplexing equipment or satellite links are not
     supported.

     DECmux 308/316/332

     The DECmux 300 requires a synchronous connection to a MUXserver
     300 for proper operation.

     The DECmux units are available in the following configurations:

     o  Eight EIA 232-D/CCITT V.24 ports with modem control (DECmux
        308)

     o  Sixteen EIA 232-D/CCITT V.24 ports with modem control (DECmux
        316)

     o  Sixteen DEC423 ports, data leads only (DECmux 316-B)

     o  Thirty-two DEC423 ports, data leads only (DECmux 332)

     The eight and sixteen port units are field upgradable using
     the following upgrade panels kits. After installation, the new
     configuration is automatically reconfigured and the DECmux is
     initialized to factory default settings.

     o  Eight EIA 232-D/CCITT V.24 ports with modem control

     o  Sixteen DEC423 ports, data leads only

     The DECmux 300 EIA 232-D ports are compatible with the Digital
     family of modems and with Bell 100 and 200 series modems and
     their equivalents.

     A BREAK feature is available and can be set on a per-port basis.
     This allows the DECmux 300 to force a break condition on connec-
     tions to host interfaces. BREAK can also be passed through from
     a terminal connected on the server to the non-LAT host connected
     on the server.

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     MUXserver 300 Remote Terminal Server for VMS,       SPD 25.E9.02
     Version 1.2


     Server Management

     The MUXserver 300/310 supervisory port can accept directly con-
     nected asynchronous terminals with the following characteris-
     tics:

     o  DEC423 asynchronous start/stop transmission, having 8 data
        bits, 1 start bit, 1 stop bit, and no parity.

     o  Full duplex with XON/XOFF flow control

     o  Speed selectable from one of the following: 300, 600, 1200,
        2400, 4800, 9600 baud, or AUTOBAUD

     Several facilities exist for managing and troubleshooting server
     operation. The Server Manager in privileged mode can set up
     server identification information, change port characteristics,
     or fine tune the operating characteristics of the server. The
     Server Manager can also assign service names to groups of one
     or more ports that are connected to non-LAT hosts or modems.
     Troubleshooting facilities include diagnostic tests, a remote
     console feature, and online statistics.

     A privileged user can diagnose Ethernet communications prob-
     lems by looping messages to an Ethernet host and through the
     Ethernet hardware interface at the server. To diagnose terminal
     problems, users can execute a command to transmit test data to
     their terminal, or the server manager can send test data to any
     terminal.

     A privileged user can also diagnose synchronous line problems
     by looping test messages between adjacent MUXserver 300/310 and
     DECmux 300 units.

     The capability also exists for the server manager to test a
     service connection by sending data from the initiating port to
     the service node and back again. The data is then compared and
     any discrepancies reported. At the service node, the data can
     be looped back by the LAT protocol, or internally or exter-
     nally at the service port. This feature is supported only by

                                    13

 


     MUXserver 300 Remote Terminal Server for VMS,       SPD 25.E9.02
     Version 1.2


     MUXserver/DECmux 300 service nodes; VMS service nodes do not
     support this service loopback capability.

     The server maintains a variety of statistics and counters. These
     include the following: Synchronous composite data link statis-
     tics, Ethernet data link statistics, LAT protocol statistics,
     and port error statistics. This data can be displayed and zeroed
     by the Server Manager. Server parameters that can be modified
     and displayed include the server identification, circuit timer,
     session limits, and login limits.

     Remote Server Management

     The MUXserver/DECmux 300 implements the console carrier feature,
     which enables access to the MUXserver/DECmux 300 local mode from
     a Phase IV DECnet host on the same LAN. With the exception of
     remote console port configuration, the entire local mode user
     interface is accessible to the remote console carrier user. This
     includes the privileged commands, if the user knows the server's
     privileged password. This capability allows centralized server
     management and remote server diagnosis.

     Operation

     The MUXserver ROM-based firmware provides the necessary main-
     tenance operation protocols for down-line loading MUXserver
     software from a load host, over the Ethernet, into server mem-
     ory. All self-test diagnostics are in MUXserver ROM; down-line
     loading is not a precondition for MUXserver self-test.

     In the event of a bugcheck caused by a fatal error, the unit
     will normally attempt to up-line dump server memory to a DECnet
     Phase IV host. Following this, the unit will automatically
     initialize itself, execute the self-test routines, and if still
     operational, invoke a down-line load.

     Once the MUXserver down-line load is complete, the network will
     self-configure and communications will be established with the
     remote DECmux 300.

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     MUXserver 300 Remote Terminal Server for VMS,       SPD 25.E9.02
     Version 1.2


     The remote DECmux 300 operates on ROM-based firmware; oper-
     ational characteristics are stored in non-volatile RAM. The
     remote DECmux 300 does not require down-line loading but does
     require a connection to a MUXserver 300 for operation.

     Configuration and Performance

     The process of configuring the MUXserver/DECmux 300 network is
     based primarily on tradeoffs of cost and performance within
     the realm of satisfying user application requirements. The
     performance of a given network depends on several factors.

     o  Composite port speed

     o  Number of route through composite ports

     o  Number of terminals

     o  Number of host systems with active connections to the server

     o  Number of active connections to non-LAT hosts

     o  Terminal speeds

     o  Terminal user applications

     o  Number and size of host buffers

     o  Terminal workload

     o  Host workload

     In order to achieve a viable configuration, the user and/or a
     Digital software specialist should perform a level of appli-
     cation analysis that addresses the factors above. The actual
     maximum data throughput cannot be calculated by multiplying the
     number of lines by the line speed since many factors may reduce
     the actual throughput.

     Restrictions on MUXserver/DECmux 300 Usage

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     MUXserver 300 Remote Terminal Server for VMS,       SPD 25.E9.02
     Version 1.2


     While terminal connections using the MUXserver/DEC-mux 300 have
     been designed to simulate direct terminal connections, a few
     differences exist because of the nature of the product. Under
     most circumstances, these differences are not noticed by termi-
     nal users or service node application programs. However, appli-
     cations that are directly dependent on the following functions
     may not operate as with a direct connection:

     o  Setting the terminal speed, character size, and parity by
        manipulating system data structures

     o  Extremely fast response time (typically less than 200 ms) to
        operate

     o  Applications that use an alternate terminal driver in the
        service node

     o  Applications that expect incoming connections to have fixed
        device names

     HARDWARE REQUIREMENTS

     VAX, MicroVAX, VAXserver, or VAXstation configuration as speci-
     fied in the System Support Addendum (SSA 25.E9.xx-x).

     SOFTWARE REQUIREMENTS*

     VMS Operating System or MicroVMS Operating System
     DECnet-VAX

     *  Refer to the System Support Addendum for availability and
        required versions of prerequisite software (SSA 25.E9.02-x).







                                    16

 


     MUXserver 300 Remote Terminal Server for VMS,       SPD 25.E9.02
     Version 1.2


     ORDERING INFORMATION

     Software Media: QA-VT7A*-**
     Software Documentation: QA-VT7AA-GZ
     Software Product Services: QT-VT7A*-**

     *  Denotes variant fields. For additional information on avail-
        able licenses, services and media, refer to the appropriate
        price book.


     SOFTWARE LICENSING

     The MUXserver 300 software is licensed to execute on the
     MUXserver 300/310 hardware and the license is supplied with
     the hardware. No additional license is required for either a
     load host CPU or a service host.

     This product does not provide support for the VMS License Man-
     agement Facility. A Product Authorization Key is not required
     for installation or use of the product.

     This software is furnished under the licensing provisions of
     Digital Equipment Corporation's Standard Terms and Conditions.
     For more information about Digital's licensing terms and poli-
     cies, contact your local Digital office.

     SOFTWARE PRODUCT SERVICES

     A variety of service options are available from Digital. For
     more information, contact your local Digital office.








                                    17

 


     MUXserver 300 Remote Terminal Server for VMS,       SPD 25.E9.02
     Version 1.2


     SOFTWARE WARRANTY

     Warranty for this software product is provided by Digital with
     the purchase of a license for the product as defined in the
     Software Warranty Addendum of this SPD.

     [R]  IBM is a registered trademark of International Business
          Machines Corporation.

     [TM] Bell is a trademark of Bell Telephone Companies.

     [TM] IBM PC, IBM PC/AT, and IBM PC/XT are trademarks of Interna-
          tional Business Machines Corporation.

     [TM] The DIGITAL Logo, DEC, DECconnect, DECmate, DECnet-VAX,
          DECserver, DECstation, DELNI, DESTA, LA50, LA75, LN03, LN03
          PLUS, LN03R, MicroVAX, MicroVMS, MUXserver, Professional,
          Rainbow, VAX, VAXmate, VAXstation, VAXserver, VMS, and VT
          are trademarks of Digital Equipment Corporation.




















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