ms/http_max_ports is a SAP Parameter attribute which is used to control Maximum number of listening HTTP ports 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 .
Number of ports on which the message server can receive HTTP and HTTPS
connections. The number of virtual hosts is determined by this
parameter. The total number of HTTP, HTTPS, and virtual hosts must not
exceed this value. These are defined with the
See SAP Parameter Documentation for full SAP documentation for this profile parameter.