 HTTP/VTAM Conversion - To connect Web users to legacy 3270 mainframe-based applications like CICS and IMS, VIRTEL combines a VTAM relay and an HTTP server. The TCP/IP HTTP connection between the browsers and VIRTEL is asynchronous (disconnected mode). The VTAM connection between VIRTEL and
the 3270 applications is synchronous (connected mode).
Time-proven VIRTEL VTAM relays manage the VTAM sessions with the
3270 applications. Web users are connected through dynamic LU pools. Where 3270 emulation
would create 1,000 IP sessions for 1,000 connected users, VIRTEL creates only 10 to 50 IP sessions,
a significant memory saving.
On-The-Fly Conversion - A customized HTML template, which contains VIRTEL tags and JavaScripts guides the on-the-fly conversion between 3270 and HTML worlds for colors, font, cursor, PF keys, etc. One customized HTML template is enough for all your 3270 applications. Several templates can be
developed to offer different Web presentations to different users or
for different applications.
Mainframe-Based Solution - Written in
fast-executing Assembler, VIRTEL runs on the mainframe hosting
the 3270 application. There
is nothing to install or run outside the mainframe. Compared to multi-tier solutions where several layers of
code, including slow-executing Java,
run on several platforms, the VIRTEL solution provides much better
performance
and scalability.
Genuine "Light" Client - The workstation is a simple Web browser. There is no additional code to install. Web users simply point their browser to a predefined URL (http://host-IP-address:port# as instructed by email or Intranet) to access the 3270
applications through VIRTEL. VIRTEL transforms the
3270 applications into Web servers.
Two-Tier Solution - VIRTEL allows deploying very simple two-tier solutions that
include no applets, no middleware, no CICS system exits, no modification of legacy code or printing . none of the complexity, bottlenecks, and weaknesses associated with
multi-tier solutions.
Compatible With Multi-Tier Solutions - However, VIRTEL can be inserted in a multi-tier solution between the 3270 applications and another
Web server to
function as a 3270 application server, and to benefit from
VIRTEL's
outstanding "by-design" scalability, performance, and
security.
Ergonomics and Features - To transform legacy 3270 applications into full-featured Web
applications, an endless list of new Web-specific ergonomics
and features can be added to the 3270 applications through the development of HTML templates, JavaScripts, and VIRTEL scripts:
- Background style, colors, frames, fonts
size and color, PF Key display, usage of extended attributes,
etc.
- Pop-ups for display and guidance
- Clickable icons: Print-Screen, Print-Session, language choice, style sheet, etc.
- Selection boxes: binary, combo, etc.
- Assisted data entry: zip code, address or geographical data, dates (display of calendar with clickable days), etc.
- Calls to other Web servers to retrieve and display any
kind of information: zip codes, area codes, image files (for example: past written correspondence),
etc.
Enhanced Web Navigation - Unless VIRTEL Web
Modernization is deployed to change the 3270
navigation, the screen-by-screen navigation of the
legacy 3270 application remains unchanged (One Web
page per 3270 screen).
However, the navigation within a screen can be facilitated
by making some fields clickable instead of having
to enter an "x" and to press the enter key. The
navigation is also enhanced by the availability of
the Web backward/forward arrows, which allow navigating
locally (at the client level) using the cached version
of the previous/next screens, as VIRTEL automatically
re-synchronizes with VTAM sessions.
Security - VIRTEL Web to Host is compatible with any proxy, firewall, SSO gateway,
SSL security box, Web-application server, or other IP-security component that send HTTP requests to it, sometimes including a user password. VIRTEL rules can be set to filter and switch authorized RACF, ACF2, or TSS users to the desired transactions and enforce security in a strict yet flexible manner that takes advantage of existing
mainframe-defined security. Unlike with Telnet
connectors, the SNA communication is not extended over the Web,
which would create a security exposure. Additionally, a
VIRTEL script can check that the user didn't inadvertently jump out
of the application.
Scalability and Performance
- VIRTEL's outstanding scalability and performance are due to its simple two-tier 100%
mainframe-based design and the fact that it is developed in fast-executing Assembler code
rather than performance-challenged Java code. Compared to other solutions:
- Less code is executed
- All executed code resides centrally on the mainframe close to
the 3270 applications
- Memory consumption is reduced by the
smart management of IP sessions
- Network traffic is reduced because VIRTEL runs next to
VTAM and 3270 applications
- There are none of the bottlenecks and weaknesses typically
associated with middleware, intermediate servers and code
layers, multiple applets, and complex connectors
- The fact that no additional code needs to be loaded on the clients improves their
performance, especially those with low bandwidth connections
The flourishing market of Web and network monitoring products
is an indication of the severity of bottlenecks and other
networking weaknesses with middleware and multi-tier based
solutions. But VIRTEL has been successfully used in production with up to 15,000 simultaneous VTAM sessions by one of its current users,
and its true scalability and performance limits have yet to be reached. We invite you to test VIRTEL's
performance with your own 3270 applications on your own
mainframe and to use a workload simulation product if available. Click here for a free VIRTEL evaluation.
Reliability and Availability - The VIRTEL
solution is as reliable and available as the mainframe
it runs on. With VIRTEL, there are none of the weaknesses
associated with multi-tier solutions.
3270 Support - VIRTEL runs under MVS (OS/390, z/OS)
or VSE (2.51 and above) in a TCP/IP, 3270, 3278, or 3287
environment. Besides BMS (COBOL CICS) and MFS (IMS) maps,
VIRTEL Web to Host supports any other map generated by 4GL,
Natural, Ideal, etc. VIRTEL's numerous installation
parameters allow complete tailoring to the 3270 applications
for support of extended attributes, reuse of RACF-ACF2-TSS
user and password data, forced LU assignments, etc.
Multilingual Support - VIRTEL (4.27 and above)
supports the automatic conversion of SBCS and DBCS (Single and
Double Byte Character Sets) to and from Unicode. One of
VIRTEL's customers has made a Chinese DBCS version of one of
their IMS applications and they use VIRTEL to translate it to
Unicode. Language conversion triggering tags and JavaScripts
can be included in VIRTEL's HTML conversion template for
Chinese, Japanese, Korean, Hebrew, etc.
IP Standards Support - VIRTEL includes an HTTP, and
optionally an SMTP server. Requests come through HTTP, and
optionally emails. Answers can embed any 3270 data flow in
any IP standard format depending on the template used (HTML,
XML, Excel, email, Word, etc.). This support of all commonly
used IP standards allows extending 3270 applications to the
Web with minimum effort.
Print Support - 3287 data flows open a new window in
the browser from which any authorized printer on the network
can be addressed. JavaScript Print-Screen and Print-Session
buttons can be added to the Web pages.
Quick Start - It takes only two hours for the
Systems Administrator to install and tailor VIRTEL, which
instantly opens the 3270 applications to the Web using the
default presentation template. Development is limited to the
customization of a single HTML template for Web presentation
and ergonomics. In order to accelerate its deployment,
VIRTEL's technical support can supply a default presentation
template pre-customized to the buyer's presentation
requirements. An HTML JavaScript programmer takes over the
addition of Web-specific presentation, ergonomics, and new
features.
No Legacy Change - The 3270 application code remains
unchanged. No CICS system exit is required.
Centralized Support - The management and support of
the solution are 100% centralized on the mainframe where
VIRTEL is installed. This drastically reduces support
requirements and costs, when compared to other architectures
where code can be dispersed on multiple tier and platforms,
and on hundreds or thousands of clients.
Skills Requirements For the administrator
the skills requirements are limited to existing S/390
administration skills (software installation, networking,
CICS, RACF, etc) and the new skills requirements are
limited to the simple VIRTEL installation and tailoring.
It typically takes less than 2 hours to install and
set-up VIRTEL. That is all it takes to extend
the 3270 applications to the web! For the developer
the skills requirements are limited to HTML, JavaScript,
and optionally VIRTEL script (10 simple commands).
For the Web user already familiar with the 3270 application,
no additional skills are required.
Download (PDF) : VIRTEL
WEB Access
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