InterSession Web Gateway

Say Goodbye to ...

TN3270 clients & middleware,
TN3270 admin & support overhead,
TN3270 interdepartmental logistics,
TN3270 security vulnerabilities,
and more,
with InterSession Web Gateway Mainframe based 3270 Emulation
  • No installation or support required outside the mainframe
  • Securely delivers 3270 screens as HTTPS web pages simulating true 3270 TE functionality
  • Standard web browser is the client - no plugins or middleware
  • Free iPad & Android Apps for best Tablet UX
  • Significant savings over TN3270 Emulators
Web Gateway Introductory Guide

Over 40 Years of Mainframe Solutions

Data 21 Enterprising Software

Data 21, the Data 21 logo, and all other Data 21 software product and service names are trademarks of Data 21. All other trademarks belong to their respective companies. © Copyright 2026 Data 21. PKZIP®, PKWARE®, SecureZIP® are trademarks of PKWARE® and are not affiliated with Data 21.

Data 21

About Data 21

Founded in 1980, Data 21 Inc. is a veteran-owned enterprise software company headquartered in California. For over 45 years, we have delivered innovative, reliable, high-performance mainframe-centric solutions that power today’s connected enterprise.

Our software is embedded in the critical daily operations of hundreds of enterprises worldwide — a testament to our commitment to exceptional engineering and long-term client success. We don’t just support our customers; we evolve alongside them.

At Data 21, the mainframe isn’t a legacy constraint — it’s a strategic foundation.

This site uses cookies. By continuing to browse our site you are agreeing to our use of cookies.