What Is Baan Session?
Also known as: LN session, session code, Baan session code
Definition
A Baan session is the atomic executable unit of Baan and Infor LN - one screen, report or batch program - identified by a coded name such as tdsls4101m000, where the letters give the package and module and the digits give the session number.
Baan Session Explained
Every user-facing function in Baan and Infor LN is a session. Maintaining sales orders is a session, printing a picking list is a session, running a planning job is a session. Each one is defined in the Tools data dictionary with a form layout, a main table, a set of authorized commands and a 4GL script that supplies the behavior. Because sessions are first-class objects, they are also the unit of authorization, of menu placement and of customization.
The naming convention is what makes the system navigable. A code like tdsls4101m000 breaks down as a two-character package (td for distribution), a three-character module (sls for sales), a four-digit session number, a letter indicating the session type, and a three-digit version. The trailing letter distinguishes categories such as a multi-occurrence maintenance session from a single-occurrence session, and the number ranges group display, maintain, print and process functions in a broadly consistent way across modules.
Experienced practitioners work by code rather than by menu. Support tickets, documentation and consultant conversations all reference session codes because they are unambiguous across languages and menu configurations. Most environments let a user start a session directly by typing its code, which is far faster than navigating a menu tree and is essential when following written instructions that were produced for a differently configured site.
Sessions also matter technically. Customization historically meant modifying a standard session's script in a derived VRC, which is precisely what makes upgrades expensive. The modern LN approach attaches extension code to defined points on the standard session instead, leaving the standard object untouched. When someone asks how customized an environment is, the honest answer is a count of modified sessions and extended sessions, not a subjective description.
Why It Matters
- Session codes are the universal language of Baan and LN support, so knowing them cuts diagnosis time dramatically.
- Authorizations are granted per session, making the session list the practical basis for segregation-of-duties design.
- Counting modified sessions per VRC is the fastest reliable measure of customization debt before an upgrade.
- Running sessions directly by code bypasses menu misconfiguration, which is often the quickest workaround during an incident.
In Practice
When a user reports that a screen is missing, resolve it by code rather than by menu. Ask them to start the session directly. If it runs, the problem is menu or DEM configuration; if it is refused, the problem is authorization. That single test separates two very different root causes in under a minute.
Frequently Asked Questions
How do I read a Baan session code?
Read it left to right. The first two characters are the package, such as td for distribution or tf for finance. The next three are the module, such as sls for sales. The four digits are the session number within that module, the following letter indicates the session type, and the final three digits are the version. So tdsls4101m000 is a distribution, sales, session number 4101.
Can users run sessions directly by code?
Yes, provided they are authorized for that session. Both the classic and web interfaces offer a way to start a session by entering its code, and support teams rely on this constantly. Authorization is still enforced, so running by code is a navigation shortcut rather than a security bypass. If the session is refused, the user simply lacks the authorization.
Related Terms
Baan 3GL and 4GL
Baan 3GL and 4GL are the two programming languages of Baan and Infor LN. 4GL is the event-driven script attached to a session and its form fields, while 3GL is the C-like language used for libraries, DAL objects and standalone programs.
Baan/LN Tools Package
The Tools package is Baan and Infor LN's own development and administration layer. It holds the data dictionary, session and form definitions, the 3GL and 4GL compilers, VRC software layering, authorization management, job scheduling, company setup and the Exchange module.
LN Extensions
LN Extensions are Infor LN's supported customization framework: extension scripts and objects attached to standard sessions, tables and business logic through defined extension points, stored outside standard code so vendor upgrades and cloud updates do not overwrite them.
Go Deeper
Baan to Infor LN Migration Readiness Assessment
Score your organization's readiness to migrate from Baan IV or Baan V to Infor LN across ten dimensions, from data quality to executive sponsorship.
Infor LN Studio Development: Extensions Without Upgrade Pain
Infor LN Studio development guide: 4GL sessions, DALs, LN Extensions, and CDFs - how to customize LN without source modifications that break upgrades.
Baan 4GL Modernization: Strategies for Legacy Code
Baan 4GL modernization strategies: inventory legacy sessions, retire dead code, convert customizations to LN extensions, and de-risk your Baan installed base.
Working with Baan Session in a live environment? Our engineers do this every day - and our AI agents automate most of it.