expectations have changed in todays' business environment.
Corporate-Customer relationships are more complex and as
a result, companies are providing an ever increasing array
of products and services to accommodate them. The task of
managing the vast amount of data across heterogeneous systems
and networks has become a challenge.
are also under pressure to differentiate and maximize the
profitability of their services while increasing market
penetration through effective cross-selling. The foundation
for this activity is understanding customer relationships
across all lines of their business consistently, regardless
of geography. Getting data from all sources, including legacy
systems, in real time to an integrated enterprise-wide information
management system has proven extremely difficult.
addition to this, working in a global economy, the business
day is now twenty-four hours long, seven days a week. To
service this need, systems must now be integrated around
the world and provide virtually zero down-time.
and Digital's' 'Enterprise' represents
the first and foremost solution to these complex business
only long term, scaleable solution is to implement a unified,
consistent, yet flexible approach to handling transactions
and other messaging data across the entire organization
- regardless of the source or destination. To this end,
Digital and Oasis have jointly created 'Enterprise'.
This is an integrated software environment allowing fault
resilient transaction processing and delivery, real time
and batch, between virtually any end points within your
is composed of Digital's Reliable Transaction Router
(RTR) technology working in harmony with Oasis Technologies
Information Switching Technology / Message Services Infrastructure
Enterprise into existing business systems is possible
with Enterprise's Open Systems Architecture that can
operate on your existing platforms and interface with existing
transaction and message protocols. Data in legacy applications
can be accessed to support improved account management and
new business opportunities.
Enterprise, transaction and data integrity is insured
by using techniques such as message timers, two phase commit,
disk shadowing, site shadowing and journaling. By automatically
managing system failures, lost or duplicated data is avoided.
Data can now be collected from all lines of business and
across all geographies in accordance to the data model established.
the Enterprise solution; in conjunction with other
data mapping, modeling and integration services; Digital
and Oasis help organizations avoid such problems as a lack
of data integrity across multiple data-stores, inaccessible
data or information relationship-blindness. Inconsistent
views of data can now be eliminated.
and reliable support is provided for a full array of information
management tools by focusing on the key ingredient - data
- and insuring this data flows reliably and uniformly across
the entire enterprise in real time or batch. Enterprise
provides the means for managing organizational data effectively
in order to deliver higher quality services with increased
cross-selling; ultimately allowing improved profitability
and customer loyalty.
IST/MSI is an integrated real time and batch transaction
switching and processing environment, designed specifically
to handle distributed data across heterogeneous systems
and networks. IST/MSI provides virtually unlimited
message formats and message translation.
backbone architecture is IST/Foundation, thereby
taking advantage of the rich transaction processing functionality
available within that Oasis product. IST/MSI also provides
software for Session Management and high-performance database
of the main features of IST/MSI is its flexibility
and scalability. It can run on hundreds of small-end platforms
residing in branches or customer call centers, for example;
or it could also run on one large installation sitting in
a datacentre; or any configuration in between.
addition to the transaction processing power IST/MSI
provides, many special features were built to enable the
IST/MSI software to work hand-in-hand with Digital's'
RTR (Reliable Transaction Router) product in order
to provide the true 7/24 operations our customers'
is just as flexible and scaleable. Where necessary, it can
accompany IST/MSI into whatever configuration is
required by our customers.
DIGITAL Reliable Transaction Router (RTR) is disaster-tolerant,
middleware for business applications that require the reliable
execution of transactions in real time and without any interruptions
of service across widely distributed systems. RTR provides
reliable transactional messaging, with ACID properties,
between distributed client, router and server systems. RTR
takes responsibility for detecting failures in a distributed
environment and providing transparent fail-over and transaction
integrity for uninterrupted service. RTR insulates applications
from software, network and site failures.
allows the application designer to decide where to place
the application data. RTR allows data to be partitioned
over as many nodes and disks as the performance or business
requirements dictate. The location of the application data
is transparent to the applications, allowing for
easier system reconfiguration and horizontal growth.
applications may perform transactions, which access more
than one database. RTR insures (in cooperation with the
application) that transaction operations are either all
applied to the databases or are all rolled back. This is
known as all or nothing transaction semantics (2 Phase-Commit).
lets the application designer concentrate on the application,
rather than the problems of handling the network. RTR simplifies
the design of applications that are distributed across the
network, and preserves data-consistency even if components
of the system fail (including the application themselves).
provides a high degree of failure resilience and allows
continued system operation in case of node or link failures.
RTR supports shadow and standby operations to protect against
entire site failures. RTR guarantees transaction integrity
against many kinds of failures by using a transaction
RTR and IST/MSI comprise Enterprise.
ability to process financial and non-financial transactions
over large heterogeneous networks;
ability to process an unlimited number of message formats;
ability to handle an unlimited number of devices;
ability to process messages up to 4 gigabyte in size;
performance transaction switching;
API's so that customers can build their own customized
and play capabilities with other Oasis IST products;
the ability to have multiple Enterprise environments operating
within one hardware platform;
architecture running under Unix and NT;
comprehensive Data Base Management layer allowing you
to connect to a range of databases (i.e. Oracle, Sybase,
Spawning' (one-to-many) provides you a unique solution
for highly complex transactions;
quality and reliability;
automated and instantaneous fail-over capabilities to
allow for a true 7 by 24 operating environment;
with disaster recovery strategies that call for geographically
commit order integrity across distributed and/or mirrored
to work in a lights-out datacentre paradigm;
is based on proven technology and available products. Today,
IST provides financial transaction and messaging
services at over 120 sites in more than 40 countries. Citibank,
MasterCard, Visa, Diners Club, Europay, Bejing Golden Card
and many others are using Oasis' Information Switching
Technology to route financial messages from ATMs and POS
terminals, provide EFT transaction routing, provide full
or partial authorizations, transaction reporting and electronic
draft capture (EDC), and store-and-forward processing all
in a completely secure, encrypted environment. It supports
many shared-cash networks, such as VISA and MasterCard.
It has been distributed across multiple machines on both
Local and Wide-Area Networks.
is used worldwide by some of the world's most demanding
clients to provide a distributed fault-tolerant infrastructure
for their transaction systems. Many of the world's
stock and option exchanges use RTR; Swiss Electronic Bourse,
American Stock Exchange, Hong Kong Futures Exchange, Amsterdam
Stock Exchange, Australian Stock Exchange, Ced Borsa (Milan)
and others. RTR can be found where transaction integrity
is a must; Banking, Citibank, Bank Austria; Transportation,
Polish Railways (PKP), India Railway and Information Services,
Reuters. At over 250 customers RTR provides transaction
reliability, every day, all day for every transaction.
Your Business Needs
is ideally suited to help your organization integrate their
transaction based systems and data; on a regional or global
basis. Some typical uses for the product are :
Transaction Processing & Electronic Commerce
can work hand-in-hand with the entire Oasis family of products.
As such, customers have the flexibility of taking advantage
of these plug-and-play systems :
- to handle all ATM, POS, Credit and Debit Card processing
- is a fully integrated Clearing and Settlement Package;
- is a back-end Card Processing system for issuers and
Oasis Family of Products is illustrated in the following
RTR is a licensed product of the Digital Equipment Corporation.
transaction processing engine of Enterprise resides within
IST/MSI component. IST/MSI uses four conceptual layers to
perform processing: the Communications Driver, the Agent,
the Transaction Managed Processor (TMAP) and the Gateway(s).
The communication driver forms the link between outside
networks and IST/MSI. The Agent(s) work as translators converting
data from some external format into the IST/MSI internal
format. The TMAP processes and routes the transactions.
The Gateways allow MSI to interact seamlessly with Digital's
Reliable Transaction Router (RTR) product.
communicates between all processes using ELF (Elementized
Format) messages (based on the ASN.1 Standard). ELF is a
series of containers that can hold arbitrary data fields,
or groups of data fields. The result can be a simple linear
set of data fields to a complex hierarchical structure.
IST/MSI uses only ELF messages to communicate internally,
both for transaction processing and process administration.
following diagram shows a typical Enterprise configuration,
allowing for 7/24 operation.
provides for the concept of 'Spawned Transactions'.
This means that a single transaction initiated at some end-point
(super-transaction), may automatically spawn multiple sub-transactions
is this an advantage? Here is an example. A customer enters
a bank branch and wishes to have a complete profile of all
the business that they do with this bank. This would mean
all the household information, account information, brokerage
information, insurance information, etc. available on that
would be a very large transaction that may have to go to
multiple host and local databases in order to retrieve the
desired data. By splitting the transaction into sub-transactions,
the bank representative is not forced to wait for the entire
transaction to complete before being able to begin serving
this customers needs. As the sub-transactions complete,
the representative will be able to see more and more profile
information on that customer. If one sub-transaction fails,
it does not mean that the entire query would fail. A diagrammatic
representation of this can be found in the following section
entitled "Example Enterprise Application".
the above example, a client terminal initiates a request
(1) to Enterprise. That request goes to a local database
and retrieves some information (1a) and returns it back
to Enterprise. Based on some of the information returned,
Enterprise automatically spawns another transaction (2)
which is sent to Host 1. Simultaneous to this, response
1a is sent back to the requester.
1 responds with response 2a. Based on data within this reply,
two additional transactions are generated (3 and 4). These
are sent to Host 2 and Host 3, respectively. The first host
response (2a) waits in Enterprise until a 'More'
request is initiated by the client. A 'More' request
is asking if there is any further data to the original request.
At this point, the 2a reply is sent back to the requester.
some point in time, Host 2 and Host 3 reply back to Enterprise.
Their respective replies (3a and 4a) are suspended (held)
within the system. When an additional 'More' request
is initiated, those replies are sent back to the client.
In this example, that original transaction is now complete.
fault resilient capability of Enterprise is achieved through
the RTR components. RTR divides the transaction system into
clients (requesters), servers and the interconnection between
them, the router. The client component of RTR manages the
interface between the user and RTR router.
RTR Server component manages the interface between the server
and RTR router; the router manages the integrity of the
interconnection between the client and the server. Together
they isolate the user and the server from failures, in the
network and the servers and the need to know when a client
or server has moved or been added.
architecture considers each RTR component as running on
a node; front-end nodes, back-end nodes and
router nodes as shown above.
RTR client processes run on the front-end nodes. This layer
allows computing power to be provided locally at the end-user
site for transaction acquisition and presentation.
RTR server processes run on the back-end nodes. This layer
allows the application (and database) to be distributed
geographically, and permit fault tolerant systems to be
constructed which cope with either node or site failures.
RTR router normally contains no application software. This
layer reduces the number of logical network links required
on front-end and back-end nodes. It also de-couples the
back-end layer from the front-end layer so that configuration
changes in the (often rapidly changing) user environment
have little influence on the transaction processing and
database (back-end) environment.
RTR is based on a three-node model, it is not necessary
for all three nodes to be physically present. For systems
with few front-ends, the router and front-end layers can
be combined. The physical locations of the front-end, router
and back-end nodes are specified using RTR configuration
configuring and managing RTR to provide the level of fault
tolerance desired the user can specify a server to have
a specific role.
servers are separate back-ends, which handle the same
transactions in parallel on identical copies of the database.
The databases are mirrors. In Figure 5 the main server (Smain)
is at site 1 and the shadow server (Sshdw) are at site 2
both receive every transaction. Should site 1 fail, site
2 continues to operate, and the service is uninterrupted.
When the failed back-end node restarts, the transactions,
which had not been committed by the servers at the time
of the back-end failure, are replayed to the servers from
a disk journal.
are "spare" servers, which automatically take
over from the main back-end if it fails. This take-over
is transparent to the application. The above diagram shows
a possible RTR configuration. The main server (Smain) runs
on one node while the standby server (Ssby) runs on the
other node (both have access to the same database). The
standby server is active, but RTR does not pass transactions
to it. Should the first node fail, RTR starts passing transactions
to the standby server. Concurrent servers are servers
running on the same node. This is useful for increasing
throughput, especially when the database only allows one
active transaction per process.
the RTR Router is the heart of the fault management, multiple
routers are usually configured. Front-end nodes will automatically
find another router if the one being used fails. This reconnection
is transparent to the application. Front-ends may also be
configured to choose routers with the least loading. If
the original router coordinating a transaction fails, the
back-end nodes select another router that can ensure correct
architectural services consist of five elements:
mailbox is a basic resource that all IST applications use
to communicate with other applications. It is essentially
an address, or a location on the network, where processes
may send and receive messages.
mailbox manager provides the run-time message communications
environment for IST/MSI applications, employing mailboxes
that use semaphores and shared memory to allow inter-process
communication. The IST/MSI communications components responsible
for routing transaction messages through the system all
utilize the mailbox system. These components each possess
an inbound and outbound mailbox to simplify the direction
of message traffic within the system.
are unique to the applications that use them. Each application
may have one or more mailbox sub-systems operating on their
behalf. By analyzing mailbox attributes, the Mailbox Manager
will determine the appropriate message routing within the
task is any process that is running or will be run within
Task Manager creates and monitors tasks (processes) within
the system and ensures that they execute properly. If a
task should fail, the Task Manager will attempt to re-initialize
message port is an intermediary between a communications
driver in IST/MSI and a physical communications link to
an external network or device. It provides the actual link
to the network.
port manager starts and monitors system tasks associated
with message ports. For example, it starts each communication
driver in the system. The port manager is responsible for
establishing, maintaining, monitoring, and shutting down
the connections between tasks and the communication drivers;
it is not involved in the actual transfer of transaction
messages throughout the system.
port manager also permits multi-port management and control.
event manager is an IST/MSI service that handles timer events
for the system as a whole. Applications responsible for
message routing call upon the event manager to time transaction
responses from devices, other IST/MSI applications, and
hosts or external networks. Once an event is created, the
event manager monitors it and notifies the requesting application,
through its mailbox, when and if the event expires before
the transaction processing is complete.
Application Manager (APM) tracks the initialization/state
of each process according to run-level. A run-level is a
global stage of IST/MSI's initialization. To prevent
data sharing problems, IST/MSI processes are started, run,
and terminated according to run-levels, which the APM manages.
The APM also receives manual requests from a command level
interface, allowing the management of higher level processes.
Platform Services (GPS)
Platform Services (GPS) is a layer within IST/MSI that provides
key services to other components of IST/MSI, such as the
mailbox subsystem, task management, application management,
and file service handling.
communications driver is responsible for sending a message
to the Agent. It strips the header information from the
message and performs a parity check to verify the integrity
of the data. Similarly, the Agent sends messages directly
to a specific communications driver that has been written
for a specific network. The communications driver sends
the message to a network through its port.
communications driver is programmed to handle a specific
networking protocol. A switch handling multiple protocols
will have multiple communications drivers. Typical examples
of communication drivers would be X.25 and TCP/IP.
IST/MSI Agent is a data normalizer. It functions as a translator
between message formats. It determines a message's type,
source, and destination. The Agent then creates a destination
message from this information and sends it to the appropriate
process, via the mailbox sub-system.
Agent transmits messages between the Communications Driver
and the TMAP. Each Agent is configured to translate a specific
message format and to communicate with a specific Communications
Driver. However, the Agent is not limited to a specific
TMAP process, and may send messages to any TMAP process.
Typical examples of Agents are ISO8583 translators, CGMS
translators, Visa agents, Mastercard agents, etc.
Managed Processor (TMAP)
Transaction Managed Processor (TMAP) provides the application
functionality for transaction processing. The TMAP processes
transactions by following scripts contained in the Transaction
Document (TDOC). The TMAP reads the instructions contained
in the script and executes the Application Units (AUs) specified.
TMAP exists in memory as a combination of the TMAP modules,
which use a series of resources to process transactions.
The TMAP consists of the TMAP driver, the Classifier, the
Parser, and the Script Executor.
Classifier determines message types. It looks at an ELF
message, reads its data elements, and determines which script
the TMAP will use to process the transaction. The Classifier
then returns the ID of the script to the TMAP.
TDOC contains scripts that describe how to complete an application
process. Each script consists of several steps. The steps
of a script direct the TMAP to call Application Units (AUs)
to evaluate or calculate data for the transaction being
following diagram represents a TDOC as seen in a theoretical
Client & Server Gateways
processes provide the interfaces between the IST/MSI and
the Digital RTR product. These gateways link the IST/MSI
transaction id's to RTR channels. They also provide
for parts of the protocol used for transaction execution.
is a specialized TMAP which interfaces with the RTR channel
model. It provides a tightly coupled scheme for ensuring
that RTR transactions are equivalent to database transactions.
This is because RTR considers the activity on the RTR channel
to be directly indicative of the state of the database transaction.
order to fully implement the IST/MSI Two Phase Commit protocol,
a standard application skeleton is employed within TMAPR.
is usually used within TMAPR. It provides a high performance
interface to database systems that support stored procedures.
It translates the IST/MSI internal message format (ELF)
directly into stored procedure arguments, and vise-versa.
All execution is pre-parsed where possible to insure optimum
Application Unit (AU) is the code that is executed under
the direction of the TDOC script, and performs all of the
transaction-related application processing for the TMAP.
Technology Ltd. and Digital Equipment Corporation provide
a complete solution for your enterprise-wide transaction
integration, switching and messaging business needs. A full
range of services, including support, education, publications,
and project management accompany the Enterprise solution.
IST suite of products is a highly adaptable set of
switching software and application 'building blocks'.
It can be modified to suit any business based transaction
processing requirement. There are no limitations to the
number of devices it can control and it can operate on any
UNIX or NT platform. The architecture is scaleable from
small branch or regional applications to global enterprise
solutions. Many of IST's features are user-configurable,
allowing users to personalize and customize the product
to suit specific needs.
provides a geography independent delivery mechanism for
fault resilient transaction processing over heterogeneous
is a 'Universal Message Integrator', allowing
our customers to integrate, process and communicate data
from many disparate sources regardless of where the data
is in the world.
allows them to do it every minute of every day.
one of the largest banks in the United States found this
to be true. So will you.
to make it work for you?
and Oasis offer a range of services to help you be successful
with Enterprise. Digital brings solid experience
in managing large complex integration projects. As a Digital
partner Oasis Technology has proven product, technical and
support expertise in the field of transaction processing.
As a team Digital and Oasis have a proven track record of
and Oasis have the experienced staff to help you select
the features of Enterprise you need, design the distributed
Enterprise environment required to service your organization,
and install your systems.
can help you develop the applications and build your databases.
has technology migration services to help you move existing
applications to Enterprise.
and Oasis offer educational seminars, self-paced training
and classes to develop the skills of your staff to fully
exploit the features of Enterprise.
from Digital and Oasis, a solid foundation for the next