UniAccess is designed and implemented to fully
utilize Unisys OS 2200 system software to the
greatest degree possible. The UniAccess Transaction
Server system-level components that interact with OS
2200 communications, scheduling, and transaction
monitoring processes include the UniAccess
Communication Server (UACS) and the UniAccess
Fixed-gate (UAFG). Other components of UATS include
the UniAccess Server-Library, the UniAccess ODBC
Driver, and the UniAccess Distributed Transaction
Coordinator. These components act together to
transform the Unisys 2200 into a
Microsoft-architecture compatible server by
performing the following functions:
- establish and manage the
client/server interaction
- interoperate with client
applications or SQL Servers using the TDS
protocol
- process client requests
through ODBC and Open Client interfaces
- perform host-to-client
datatype conversions
- manage error, information,
and security control messages
All of the client and server-side
components listed below are packaged together,
priced, and licensed under the product name of
UniAccess Transaction Server. UATS makes it possible
for a multitude of industry-leading development
tools, end-user query tools, and off-the-shelf
packages to interact with OS 2200 data sources
without restriction or modification.
UniAccess Server-Library (UASL) is a set of
Application Programming Interfaces (APIs) that
enable Unisys TIP transactions to act as stored
procedures in the Microsoft architecture. Using the
Server-Library functions, programmers create RPC-processing
transactions (although they may create
general-purpose SQL language transactions as well).
Client applications can then issue RPC calls through
the ODBC or Open Client interfaces. These RPCs map
to customer-written TIP transactions that access and
update any mainframe data source accessible to TIP,
interface to any other TIP transaction or resource,
and respond to the client or server that initiates
the RPC. OS 2200 batch programs may also utilize
UASL. UASL functions are accessible from the TIP
environment using the standard subroutine "CALL"
procedure. UASL provides the error-reporting
facilities common to ODBC and Open Client
interfaces.
UniAccess Communication Server (UACS) on the
OS 2200 mainframe, provides the communication link
between UniAccess on the Unisys 2200 and all other
Microsoft architectural components across the
network. UniAccess interacts across the network
using TCP/IP through either the Unisys DCP or HLC.
UACS utilizes the Unisys TSAM communications
interface, which is part of the Unisys CMS. The
operations of UACS, as well as the other
interoperability components of the architecture, are
transparent to the user, so no programming or
knowledge of its functions and protocols is
required. UACS can handle large numbers of users,
and multiple UACSs may run on a single host. UACS
utilizes the MCB for scheduling transactions to
allow existing transaction management and tuning
capabilities to be utilized.
UniAccess Fixed-Gate (UAFG) is a system-wide
shared sub-system that contains a number of core
services essential to the UniAccess System. UAFG
contains the UniAccess Data Manager (UADT) and the
UniAccess Message Manager (UAMM) that manage user,
remote server, message, and other information. It
also contains the UniAccess Server-Library. The
services provided by UAFG are transparent to the
user.
UniAccess Distributed Transaction Coordinator (UADTC)
extends Microsoft's Windows distributed transaction
capabilities to the Unisys OS 2200 environment. With
the UADTC serving as a gateway between the Microsoft
Distributed Transaction Coordinator (MS DTC) and the
UniAccess System, OS 2200
distributed-transaction-enabled resources can be
updated as part of an MS DTC-controlled transaction.
UniAccess' distributed transaction support uses
proven transaction processing technology: it is
robust despite system failures, process failures,
and communication failures; and it exploits loosely
coupled systems to provide scalable performance.
UniAccess ODBC Driver (UADriver) is the PC
component that allows Microsoft ODBC-compatible
client applications and tools to have ODBC access to
OS 2200. The driver processes ODBC function calls
from a wide variety of client tools, submits SQL and
RPC requests to UniAccess server components, and
returns results to the application. It works in
conjunction with the Microsoft supplied Driver
Manager, appearing to the application as one
processing unit.
Please note that all the components required by
UniAccess on a Microsoft Windows client or server
system are bundled at no additional cost with UATS.
With the licensing of the mainframe products, AIS
provides a no-cost license to use these desktop
components on an unlimited number of customer
systems that are connected to the OS 2200
mainframes.
