This feature is new in the Solaris Express 10/04 release.
The Internet Printing Protocol (IPP) listener feature for printing on a network works in conjunction with the Apache web server that is shipped as part of the Solaris software. IPP uses HTTP to transport requests. Using the Apache web server, the listener loads IPP print requests and processes them. The IPP listener listens on port 631 for HTTP requests and then communicates the requests to the printing system.
For more information, see the System Administration Guide: Advanced Administration.