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tcACCESS – Architecture

The tcACCESS components

tcACCESS processing is simple and straightforward: The tcACCESS communication-modules on the Mainframe (Mainframe Software) and on the Client (Workstation Software) manage the communication and the traffic between the different systems. They compensate the differences between the platforms. They assure that data is converted into the correct format (EBCDIC-ASCII) and take care that different field types are automatically adjusted.

tcACCESS allows the processing of relational and non-relational mainframe data using standard SQL-syntax. The main goal is to eliminate all programming requirements for the extraction and modification of the IBM-mainframe data. Because of SQL, standard industry interfaces like ODBC and JDBC/J2EE are supported. This guarantees a transparent and smooth integration of Client-Server- and Web applications with an IBM-mainframe system.

tcACCESS offers an API to programmatically connect to an IBM mainframe from Client/Server- or Web-applications. Client/Server- or Web-applications can invoke business logic available on the mainframe, which has been developed to meet the specific company requirements. This enables applications to use existing and proven business logic for retrieving or maintaining mainframe data. 

The modular architecture of tcACCESS guarantees a high degree of flexibility and allows for optimal implementation into company specific environments. The tcACCESS concept offers the optimal solution for all integration requirements.

tcACCESS Listener- and Scheduling-Functions

Processes that transfer and synchronize data can be completely automated using the tcACCESS Listener and Scheduling functions. The Listener functions enable a mainframe program to initiate any process on a Windows- or UNIX/LINUX/Linux on System z system. Starting an OFFICE-component (i.e. MS-WORD) directly from a mainframe online-program and passing mainframe data to the document becomes a piece of cake.

tcACCESS Administrative Functions

The tcACCESS administration functions support automatic analysis of mainframe data structures. This greatly increases transparency. Detailed information about the fields and properties of mainframe files and databases can be obtained using the user-friendly administration tool on the PC. The selection of data for further processing will be simplified, hence reducing the coordination procedures between the PC and mainframe departments. 

SQL support for all mainframe data sources

SQL-know-how is part of the base knowledge of today's programming specialists. SQL has become the industry-standard language for data manipulation. The IBM Mainframe component of tcACCESS supports SQL-based access to non-relational as well as relational data sources (SQL Engine). 


In addition to DB2, tcACCESS allows access to VSAM, DLI, IMS/DB, ADABAS, CA-Datacom, CA-IDMS etc. using standard SQL commands.

Using the tcACCESS ODBC- or JDBC/J2EE-interface a workstation- or Web-application can read and modify mainframe data-files. 

SQL functions and transactions

tcACCESS supports a variety of SQL-functions like:

  • Summarization, calculation of maximum and minimum value
  • Averaging
  • Multiple string functions
  • Date functions

Data selection across system borders has been greatly simplified. For a secure transaction processing functions „Commit“ and „Rollback“ are supported. tcACCESS provides SQL-support for DB2, SQL/DS, VSAM, DL/1, IMS/DB, ADABAS1, CA-Datacom/DB2, CA-IDMS/DB2, EDN3, KDBS, CICS-TS, MVS PDS/PS, Power Queues, SAM, SPITAB4, 3270 Screens etc.

1 ADABAS is a trademark of Software AG
2 CA-Datacom/DB, CA-IDMS/DB are trademarks of Computer Associates
3 EDN is a trademark of Wilken GmbH
4 SPITAB is a trademark of Axios Products Inc.
All other listed data sources are trademarks of IBM Corporation.

IBM mainframe data as relational tables

By default all data structures of a mainframe will be provided as relational tables. Even data structures that have been compressed or encoded for security purposes can be processed with SQL-commands by tcACCESS.


  • Support for all known data-formats, including bit-processing
  • Support for files with multiple record-types and variable data-length
  • "OCCURS" and "OCCURS DEPENDING ON" structures and other comparable structures will be treated like Virtual Tables
  • Integration of decoding routines supported for encoded data
  • 3270-screen maps and –applications are treated like a relational data source



tcACCESS consists of a base system, which can either be implemented as a CICS or VTAM application. The installation of the mainframe component requires loading the installation libraries, adaptation of table entries, allocation of VSAM files and customization of tcACCESS.


The SETUP of the tcACCESS client component only requires a few minutes. The connectivity method to the mainframe must be selected (TCP/IP, APPC/LU6.2, TELNET 3270, 3270 Terminal emulation). Based on the authority level of the signed-on user access to the mainframe data sources can be performed.


tcACCESS supports a wide variety of connectivity methods between the mainframe and the workstation. TCP/IP is one choice, but not the only one. Alternatively, traditional connectivity methods like 3270 Terminal emulation, TELNET3270, APPC or LU6.2 connections are supported as well. This guarantees a high degree of flexibility.


As an alternative to the local installation of the client component, the tcACCESS installation and configuration files can also be stored on a central file server.

For the development of Client/Server- or Web-applications with direct access to mainframe data , the tcACCESS ODBC or JDBC Server components can be used.

They allow direct data access in both directions (Host<-> Server) and the implementation of automated procedures to exchange data.

Other Systems

The tcACCESS JDBC/J2EE component allows a platform independent implementation to access or exchange mainframe data sources via TCP/IP or TELNET 3270. This component of tcACCESS is a JAVA application.


  • Easy and simple installation
  • Support of all connectivity-standards
  • Secure integration into existing environments
  • Flexible usage of existing infrastructure and network topology

Technical Requirements

tcACCESS supports the following environments:

  • IBM z/OS, zVSE, zVM, OS/390, MVS, VSE and VM
  • MS-Windows 7, MS-Vista, MS-Windows XP, MS-Windows 2000, MS-Windows NT, MS-Windows 98, MS-Windows 95, MS-Windows 3.x, WIN-OS/2
  • HP UNIX, AIX, SOLARIS, Intel or  Solaris SPARC, LINUX/Linux on System z
  • All Java-platforms
  • Supported Connections: 
    TCP/IP, MQ-Series, TN3270, SNA, LU6.2 (APPC), LU2 (3270 Terminal emulations)

Technical Requirements

tcACCESS supports the following environments: 

  • IBM z/OS, zVSE, zVM, OS/390, MVS, VSE and VM
  • MS-Windows 7, MS-Vista, MS-Windows XP, MS-Windows 2000, MS-Windows NT, MS-Windows 98, MS-Windows 95, MS-Windows 3.x, WIN-OS/2
  • HP UNIX, AIX, SOLARIS, Intel or  Solaris SPARC, LINUX/Linux on System z
  • All Java-platforms
  • Supported Connections: 
    TCP/IP, MQ-Series, TN3270, SNA, LU6.2 (APPC), LU2 (3270 Terminal emulations)