






				DIGITAL

  Software
  Product
  Description

  ___________________________________________________________________

  PRODUCT NAME:  Reliable Transaction Router[TM] Version 3.1D     SPD
  53.88.04                for Windows[TM] NT and Windows 95

  DESCRIPTION

  Reliable Transaction Router (RTR) is fault tolerant transactional mes-
  saging middleware, used to implement large, distributed applications
  using client/server technology. This version of Reliable Transaction
  Router for Windows NT enables enterprises to deploy distributed ap-
  plications on Windows NT (on both Intel[TM] and Alpha hardware) and
  Windows 95. When running on the Windows 95 operating system, only the
  client tier is supported in production environments.

  Reliable Transaction Router Version 3.1D for Windows NT and Windows
  95 is interoperable with Reliable Transaction Router Version 3.1D for
  UNIX[R] and with Reliable Transaction Router Version 3.1D for Open-
  VMS[TM]. Reliable Transaction Router Version 3.1D for Windows NT and
  Windows 95 is interoperable with Reliable Transaction Router Version
  2.2D ECO3 (or higher) for OpenVMS (see the Optional Software section
  later in this document).

  RTR provides an API for development of distributed applications us-
  ing languages such as C and C++, with optional all-or-nothing trans-
  action semantics as well as a message broadcasting capability. The API
  calls are also available from a command line interface. RTR for Win-
  dows NT and Windows 95 provides a reliable, transparent, dynamic mes-
  sage routing system that includes both a transactional and non-transactional
  message control system. Reliable Transaction Router transaction man-
  agement supports two-phase commit of distributed transactions.


							December 1997

							  AE-Q8C2D-TE




  Reliable Transaction Router[TM] Version 3.1D          SPD 53.88.04
  for Windows[TM] NT and Windows 95

  Reliable Transaction Router implements automatic software fault tol-
  erance and failure recovery on the Windows NT operating system in multin-
  ode environments by adapting to many kinds of hardware (CPU), commu-
  nications, application software, and site failures. Automatic failover
  and recovery of service operates by exploiting redundant or alternate
  hardware and network links. If alternative hardware or network links
  are not available, RTR automatically continues provision of service
  when the CPU or network link becomes available.

  Reliable Transaction Router applications are developed and deployed
  using a three-tier client/router/server software model. Client appli-
  cations call the Reliable Transaction Router "client" software tier,
  which passes messages to the "router" tier of the software. Messages
  and transactions are routed reliably and transparently, based on mes-
  sage content, to the appropriate process(es) in the "server" tier. Server
  applications typically execute transactions against a database and re-
  turn results back to clients.

  A single physical node may run one, two, or three tiers of the RTR client
  /router/server software model. Each of the three software tiers may
  consist of one or more nodes. The software model and its content-based
  routing present a "virtual", rather than physical, network to the ap-
  plication developer, providing a single view of a distributed client/server
  environment. This technique allows the application software to be in-
  dependent of physical hardware (CPU) location, network naming conven-
  tions, and communications protocol. This facilitates single-node de-
  velopment, and transparent scalability of applications to complex net-
  work configurations.

  Reliable Transaction Router software fault tolerant features such as
  router failover and shadow-server processing provide continuous com-
  puting services with completion of in-progress transactions despite
  single or multiple points of failure in the distributed client/server
  environment. Call-out servers implement user authentication control,
  and concurrent servers provide dynamic message load balancing for high
  performance. The high performance transactional messaging is imple-
  mented as a full-duplex conversation with remote server procedures us-
  ing real-time flow control techniques. These features generally re-
  quire no special user application programming logic.


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  Reliable Transaction Router[TM] Version 3.1D          SPD 53.88.04
  for Windows[TM] NT and Windows 95

  The system management interface allows the creation, deletion, and mod-
  ification of virtual networks (facilities) within a network, and per-
  mits control of distributed Reliable Transaction Router processes from
  a single system within the distributed environment. The Reliable Trans-
  action Router system management interface is used to bind the phys-
  ical hardware (CPU and communications) to a virtual network namespace
  and is transparent to the applications software. A monitoring util-
  ity can be invoked to report application performance information on
  the local node.

  Reliable Transaction Router is independent of forms/window management
  systems and databases. Multiple databases and other resource managers
  (e.g.; flat-file systems) can be updated within the same distributed
  transaction.

  Reliable Transaction Router V3.1D for Windows NT and Windows 95 is in-
  tended for distributed applications that require continuous comput-
  ing services and transaction integrity (e.g., trading/money dealing
  systems, transportation systems, telecommunications systems, and so
  on). Reliable Transaction Router can also be used for applications that
  require reliable messaging and fault tolerant application control over
  LANs and/or WANs. Reliable Transaction Router provides the enabling
  technology for applications requiring fully distributed client/server
  models.

  On the Windows 95 operating system, Reliable Transaction Router V3.1D
  can be used a frontend (i.e. client support) in an RTR application net-
  work. It is used in conjunction with Reliable Transaction Router back-
  end and router nodes to create a distributed, fault-tolerant appli-
  cation network. In addition, when running on Windows 95 Reliable Trans-
  action Router V3.1D provides router and server functionality for de-
  velopment and testing of applications on a single PC node.

  Client applications developed for Reliable Transaction Router Version
  1.1 Client for DOS/Windows can be run under Windows 95 or Windows NT
  (excluding Visual Basic applications). (This feature is provided for
  compatibility reasons; most applications will need to be recompiled
  and relinked in the new environment.)



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  Reliable Transaction Router[TM] Version 3.1D          SPD 53.88.04
  for Windows[TM] NT and Windows 95

  Reliable Transaction Router V3.1D for Windows NT and Windows 95 in-
  cludes an optional ODBC driver which allows existing ODBC-enabled ap-
  plications to take advantage of software fault-tolerance for Oracle7
  data queries when used in conjunction with a supporting ODBC server
  on the RTR backend (see the Optional Software section).

  License Types

  Reliable Transaction Router for Windows NT and Windows 95 has two li-
  cense types. The Back End license, which provides full client/router
  /server functionality, is required for nodes configured as routers or
  servers, and can also be used for nodes configured as clients. The Front
  End license provides client functionality only.

  Back End Features

  o  Runs on the Windows NT Version 4.0 operating system.

  o  Provides transparent, content-based transaction routing for client/server
     applications.

  o  Provides nontransaction based routing (broadcasts) for multiple sub-
     scription domains within a virtual network.

  o  Allows user-defined partitioned data models (content-based rout-
     ing) for improved performance of user applications.

  o  Acts as a layer between the application clients and servers, thus
     decoupling the end-to-end relationship normally required by user
     application control. This provides the application developer with
     a "single" system view of the programming environment.

  o  Ensures atomicity of transactions (all or nothing) by using a two-
     phase commit protocol for transactional message delivery among one
     or more application servers.

  o  Offers at-most-once semantics for valid transactions. This includes
     specially flagged transaction replay to a surviving application server,
     or a later instantiation of that server on the same or a differ-
     ent machine on the virtual network.

  o  Supports multiple (concurrent) servers as well as multithreaded clients
     and servers.

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  Reliable Transaction Router[TM] Version 3.1D          SPD 53.88.04
  for Windows[TM] NT and Windows 95

  o  Provides disaster protection against site failure by mirroring trans-
     actions in shadow-server environments. Automatic resynchronization
     of shadow pairs after recovery is supported.

  o  Maintains performance scaling over a wide range of configurations
     allowing easy horizontal expansion of both hardware systems and ap-
     plication software.

  o  Enables automatic failover/failback of application servers on mul-
     tiple backend systems while remaining transparent to client appli-
     cations executing on remote system(s). Reliable Transaction Router
     on Windows NT can maintain application operation in many instances
     of single or multiple failure modes in a widely distributed soft-
     ware/hardware configuration.

  o  Includes system management utilities for online control of virtual
     networks from any workstation or terminal with the appropriate priv-
     ileges. Monitoring of statistics, software and hardware states, and
     clients and servers is provided on a local node basis.

  o  Uses TCP/IP or DECnet or both as the underlying transport(s) for
     the virtual network.

  o  May be used with the AltaVista Group Tunnel, supporting secure In-
     ternet communication for any RTR connection (client to router, router
     to backend).

  o  Supports anonymous clients, i.e. allows clients to be configured
     with wildcard node names.

  Front End Features

  o  Runs on the Windows 95 or Windows NT operating system.

  o  Provides the necessary environment to run Reliable Transaction Router
     client applications under Windows 95 or Windows NT as part of a Re-
     liable Transaction Router virtual network.

  o  Uses TCP/IP or DECnet or both as the underlying transport(s) for
     the virtual network.

  o  Supports transactional and nontransactional (broadcast) messages.

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  Reliable Transaction Router[TM] Version 3.1D          SPD 53.88.04
  for Windows[TM] NT and Windows 95

  o  Supports automatic failover to another router in the event of a com-
     munication link failure.

  o  Provides full client, router and server functionality on a single
     PC for application development and testing purposes.

  o  Supports Reliable Transaction Router system management operations.

  o  Provides an optional ODBC interface and driver.

  HARDWARE REQUIREMENTS

  o  For full-function functionality, any Alpha or Intel system that runs
     Windows NT Version 4.0.

  o  For frontend functionality, any Alpha or Intel system that runs Win-
     dows NT Version 4.0, or any system that runs Windows 95 (A mini-
     mum of 16MB RAM is recommended for Windows 95 and Windows NT In-
     tel systems. A minimum of 32MB RAM is recommended for Windows NT
     Alpha systems.)

  SOFTWARE REQUIREMENTS

  o  Windows NT Operating System Version 4.0, or Windows 95 Operating
     System (frontend only). The TCP/IP protocol suite is implemented
     in the socket framework provided by the operating system.

  OPTIONAL SOFTWARE

  o  Optional software commonly used in developing and deploying Reli-
     able Transaction Router applications includes programming languages
     such as C, C++, and database software offered by third-party ven-
     dors such as Oracle Corporation.

  o  PATHWORKS 32 V7.0A or later (required for DECnet configurations).






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  Reliable Transaction Router[TM] Version 3.1D          SPD 53.88.04
  for Windows[TM] NT and Windows 95

  o  Reliable Transaction Router configurations can include a combina-
     tion of Version 3.1D Windows NT or Windows 95 nodes and Version 2.2D
     ECO3 (or later) nodes, subject to the restriction that within a given
     facility, all router and server nodes must be homogeneous with re-
     spect to Reliable Transaction Router software version (all V2 or
     all V3).

  o  Applications using the ODBC client interface require an ODBC server
     process at the RTR backend. An RTR ODBC server for Reliable Trans-
     action Router Version 3.1 for OpenVMS for use with Oracle7 is avail-
     able from Digital.

  Refer to the product's Software Product Description for more infor-
  mation on optional software products and hardware requirements and sup-
  port.

  GROWTH CONSIDERATIONS

  The minimum hardware/software requirements for any future version of
  this product may be different from the requirements for the current
  version.

  DISTRIBUTION MEDIA

  The software and documentation for Reliable Transaction Router for Win-
  dows NT and Windows 95 is available on CD-ROM. The software documen-
  tation is also available in hardcopy format.

  ORDERING INFORMATION

  Back End License:

  Software Licenses: QM-4BTAA-AA
  Hardcopy Documentation: QA-36DAA-GZ
  CD-ROM License Package: QB-4BTAA-SA
  Software Product Services: QT-4BTA*.**

  Front End License:



				   7




  Reliable Transaction Router[TM] Version 3.1D          SPD 53.88.04
  for Windows[TM] NT and Windows 95

  Software Licenses: QM-36DAA-AA
  Hardcopy Documentation: QA-36DAA-GZ
  CD-ROM License Package: QB-36DAA-SA
  Software Product Services: QT-36DA*.**

  *  Denotes variant fields. For additional information on available li-
     censes, services, and media, refer to the appropriate price book.

  SOFTWARE LICENSING

  This software is furnished only under a license. For more information
  about Digital's licensing terms and policies, contact your local Dig-
  ital office.

  SOFTWARE PRODUCT SERVICES

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

  SOFTWARE WARRANTY

  Warranty for this software product is defined in the license agree-
  ment.

  The above information is valid at time of release. Please contact your
  local Digital office for the most up-to-date information.

   1997 Digital Equipment Corporation.
  All rights reserved.

  [TM] Intel is a trademark of Intel Corporation.

  [R]  ORACLE is a registered trademark of Oracle Corporation.

  [R]  UNIX is a registered trademark in the United States and other
       countries, licensed exclusively through X/Open Company, Ltd.

  [R]  Windows 95 is a registered trademark of Microsoft Corpora-
       tion.


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  Reliable Transaction Router[TM] Version 3.1D          SPD 53.88.04
  for Windows[TM] NT and Windows 95


  [TM] Windows NT is a trademark of Microsoft Corporation.

  [TM] The DIGITAL Logo, Alpha, DEC, DECnet, Digital, OpenVMS and
       Reliable Transaction Router are trademarks of Digital Equip-
       ment Corporation.



































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