Solution for Bank

IST Switching Software

Solution For Bank (IST Switch Features)


IST/Switch is a full-function ATM, POS, EFT processor with established network interfaces supporting debit, credit and smart card transactions as an acquirer or issuer from real-world and virtual terminals, host applications or networks.  Some of its functions include:

  • Device management supporting all most ABM and Credit/Debit terminals
  • Centralized ATM management and monitoring
  • State table and FIT configuration
  • Full transaction set
  • Withdrawals from any appropriate account type
  • Fast cash
  • Deposits of Cash / cheques to any appropriate account type
  • Balance Inquiries on any account type
  • Transfers from any account to any account
  • Purchases and returns
  • Bill payment (Utilities, Credit Cards, Loans etc.)
  • Reversals of all of the above
  • Mini Statements
  • Stand-in (limits or balance-based) processing
  • Store-and-Forward processing
  • Cash only option
  • Hot/Warm card processing
  • Network interfaces to MasterCard, Visa, Amex, Interac, etc.
  • Terminal balancing
  • Electronic Draft Capture
  • Merchant management
  • Credit and debit transactions
  • Hot/Warm card processing
  • Pre-auth/completion
  • Private label card support
  • Interfaces to several security device types
  • PIN generation, verification & change
  • Message Authentication Codes (MAC)
  • Key exchange
  • Currency conversion
  • EMV processing
  • Mobile device formatting/translation



The IST/Switch Point-of-Sale (POS) server, possrv, handles credit and debit transaction messages. These are sent by POS devices installed at merchant sites. IST/Switch can talk to the following POS device brands:

  • Hypercom
  • Verifone – Tranz series
  • OMNI
  • NBS

First generation POS devices consist of a terminal and a card-swipe mechanism for entering credit card transactions. Second generation devices have an added attachment called a pin-pad through which customers can enter PIN (personal identification number) information. Pin-pads enable these devices to allow both debit and credit card transactions.
IST directly supports EFT/POS networks of any size with the POS subsystem. POS terminals can be attached through a dedicated in-store controller or linked directly to the switch, in which case IST performs the necessary polling and maintains the required connections.
IST allows the customer complete control over a POS network, with features such as:

  • Unlimited number of devices
  • Electronic Draft Capture
  • Merchant management
  • Full transaction set
  • Credit and debit transactions
  • Hot/Warm card processing

As an indication of IST’’s scalability, a single site in Brazil (Credicard S.A.) currently supports some 200,000 POS terminals, and the number is continually growing. At the moment, this represents one of the largest EFTPOS sites in the world.


IST’s operator interface allows users to monitor:

  • Real time status
  • Network status
  • Network activity
  • Process and switch control
  • Response code statistics
  • Real time technical tools

The IST operator interface is an application that allows an operator to monitor the entire IST network from one node. The monitor allows the operator to perform several tasks, such as identifying, tracking, and resolving problems.
Although this functionality is built in to the standard product, there have been instances where users prefer to use a third party or homegrown monitoring system. Again, the modular design of IST allows such interfaces to be readily developed. E.g., for the Europay project an interface to OpenView was built into the solution. If required, Oasis would be very happy to investigate building an interface into the solution for PCC.
For ATM systems, IST/Switch includes an ATM Monitor System which provides support for data collection, ATM network and device monitoring, and user interface. The functionality is divided as follows:

  • data collection from the switch (ATM availability and monitoring information)
  • connection to the Server running on the desired switch
  • login to the Server
  • windows displaying views of selected data from the switch
  • network communications management for clients
  • switch collection of data at regular intervals
  • switch data distribution to clients

The ATM Monitor software does not affect the reliability of the switch. In particular, the design does not allow unexpected events on the PC (i.e. power off, software hanging, network disconnects, disk problems, etc.) to impact the reliability of the server.


IST/Switch is a software architecture that enables messages to be passed between communicating UNIX processes. Other IST/Switch subsystems handle specific tasks such as message translation, ATM/POS device handling, transaction processing and authorization, amongst other tasks. IST/Switch provides the network mechanisms for incoming and outgoing messages on the network, as well as from dedicated devices such as POS terminals and ATM machines.

Message normalizers (formatters) translate incoming messages into a standard internal format that SHC can understand before passing them to SHC for processing. SHC sends outward bound messages to the message normalizer for translation into a standard external format, such as ISO 8583, that networks and participating financial institutions can understand.
This translation facility enables separate financial institutions to use their own proprietary systems and still exchange data, via IST/Switch, in a format that is mutually intelligible.
SHC determines what kind of processing is required by a transaction by examining the contents of each message involved in the transaction. It performs the processing, logs the results in the transaction database, and then passes any response to a normalizer for reformatting and routing back to the network and the appropriate financial institution and ATM device. Each transaction is an activity that requires a set of messages to be exchanged between an institution, IST/Switch, and an acquirer device. This transaction, when successfully completed, may result in a debit card withdrawal or a credit card purchase.


Although SHC is the IST/Switch kernel, there are other major IST/Switch sub-systems that help it to process transactions and route tasks. These are described below. This is not a complete list, however: there are other more specialized servers within IST/Switch that are not described here for reasons of space and clarity. The other major IST/Switch subsystems are:

  • The ATM subsystem server module: this manages the components of the ATM subsystem. The ATM subsystem is a modular application within IST/Switch that controls and monitors ATM terminals that are linked to the net-work.
  • The POS Server: this manages the components of the POS subsystem. The POS subsystem is a modular application within IST that controls and monitors POS merchant devices and terminals that are linked to the network.
  • The authorization server module: this controls the positive and negative authorizations of financial transaction requests from ATM and POS devices. Positive and negative authorizations are defined in the next section of this manual.
  • The settlement server module: this handles the reconciliation of net debit and credit positions between issuer and acquirer institutions at the end of the business day. The settlement server manages the database where the data for each transaction is stored.
  • The security server module: this handles the security interface between SHC and a third-party hardware security machine (HSM). The HSM provides the facility to perform PIN translation that may be needed by SHC when processing a transaction.
  • The network management server module: this handles the network management messages that IST/Switch receives from participating networks. These messages typically represent requests to initiate or close network sessions, exchange network encryption keys, initiate a cutover with a financial net-work, and other ancillary network administration tasks such as performing communications echo tests to check the robustness of the network.



Operating System and Database Platform

The proposed IST/Switch version is: release 7.3.2. The following combination of operating systems and databases are supported by this release:

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