As the connection between Lisp and tcl/tk is done via a stream, it is obvious that this connection can easily be run over a tcp socket. This allows the gui to be displayed on computers different to the one running the Lisp program. So ltk applications are not only network transparent accross different operating systems, they are actually very efficiently network transparent, since the creation of a button requires only in the magnitude of 100 bytes of network transfer. Likewise, only the generated events are transmitted back to the Lisp server.
The only difference for the lisp application to enable remote access is using the with-remote-ltk port macro instead of the with-ltk macro. As sockets are not part of the ANSI Common Lisp standard, currently only CMUCL, SBCL and Lispworks are supported by ltk-remote.
The only thing required on the client computer is tcl/tk installed and the remote.tcl script (which has less than 30 lines of code in it). Connection to the lisp process is established by
wish remote.tcl hostname portWhere hostname is the name of the computer running the lisp process and port the port on which the lisp process is listening.