wdisp/max_permitted_uri_len is a SAP Parameter attribute which is used to control Max URI length for an entry of the URI permission table information. This is available within R/3 SAP systems depending on the version and release level.
Below is the standard documentation available and a few details of the attributes values .
Maximum length of a URI in the URI permission table of the SAP Web
Dispatcher.
See SAP Parameter Documentation for full SAP documentation for this profile parameter.