I don't believe PCN-TERM has keep alive options. If becoming disconnected is your issue try using a program called Portable PuTTY. I use PuTTY extensively and it has all the options and way more.
Hope this helps. If you have any issues setting Putty up let me know and I'll send you a document on this that I've wrote for my clients. You can contact me at mike.mathieu -at- ssiop -dot- com.